• BMB Reports
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• 제47권2호
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• pp.115-120
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• 2014

In this study, we show that Mycobacterium avium subsp. paratuberculosis MAP1305 induces the maturation of bone marrow-derived dendritic cells (BMDCs), a representative antigen presenting cell (APC). MAP1305 protein induces DC maturation and the production of pro-inflammatory cytokines (Interleukin (IL)-6), tumor necrosis factor (TNF)-${\alpha}$, and IL-$1{\beta}$) through Toll like receptor-4 (TLR-4) signaling by directly binding with TLR4. MAP1305 activates the phosphorylation of MAPKs, such as ERK, p38MAPK, and JNK, which is essential for DC maturation. Furthermore, MAP1305-treated DCs transform naive T cells to polarized $CD4^+$ and $CD8^+$ T cells, thus indicating a key role for this protein in the Th1 polarization of the resulting immune response. Taken together, M. avium subsp. paratuberculosis MAP1305 is important for the regulation of innate immune response through DC-mediated proliferation of $CD4^+$ and $CD8^+$ T cells.

• The Korean Journal of Physiology and Pharmacology
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• 제18권4호
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• pp.313-320
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• 2014

The study was conducted to investigate the role of vitamin E in the high altitude hypoxia-induced damage to the intestinal barrier in rats. Sprague-Dawley rats were divided into control (Control), high altitude hypoxia (HH), and high altitude hypoxia + vitamin E (250 mg/kg $BW^*d$) (HV) groups. After the third day, the HH and HV groups were placed in a hypobaric chamber at a stimulated elevation of 7000 m for 5 days. The rats in the HV group were given vitamin E by gavage daily for 8 days. The other rats were given equal volume saline. The results showed that high altitude hypoxia caused the enlargement of heart, liver, lung and kidney, and intestinal villi damage. Supplementation with vitamin E significantly alleviated hypoxia-caused damage to the main organs including intestine, increased the serum superoxide dismutase (SOD) (p< 0.05), diamino oxidase (DAO) (p< 0.01) levels, and decreased the serum levels of interleukin-2 (IL-2) (p< 0.01), interleukin-4 (IL-4) (p<0.001), interferon-gamma ($IFN-{\gamma}$) (p<0.01) and malondialdehyde (MDA) (p<0.001), and decreased the serum erythropoietin (EPO) activity (p<0.05). Administration of vitamin E significantly increased the S-IgA (p<0.001) in ileum and significantly improved the expression levels of occludin and $I{\kappa}B{\alpha}$, and decreased the expression levels of hypoxia-inducible factor 1 alpha and 2 alpha ($HIF-1{\alpha}$ and $HIF-2{\alpha}$), Toll-like receptors (TLR4), P-$I{\kappa}B{\alpha}$ and nuclear factor-${\kappa}B$ p65(NF-${\kappa}B$ P65) in ileum compared to the HH group. This study suggested that vitamin E protectis from intestinal injury caused by high altitude hypoxia environment. These effects may be related to the HIF and TLR4/NF-${\kappa}B$ signaling pathway.

• IMMUNE NETWORK
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• 제14권6호
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• pp.307-320
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• 2014

Mycobacterium scrofulaceum is an environmental and slow-growing atypical mycobacterium. Emerging evidence suggests that M. scrofulaceum infection is associated with cervical lymphadenitis in children and pulmonary or systemic infections in immunocompromised adults. However, the nature of host innate immune responses to M. scrofulaceum remains unclear. In this study, we examined the innate immune responses in murine bone marrow-derived macrophages (BMDMs) infected with different M. scrofulaceum strains including ATCC type strains and two clinically isolated strains (rough and smooth types). All three strains resulted in the production of proinflammatory cytokines in BMDMs mediated through toll-like receptor-2 and the adaptor MyD88. Activation of MAPKs (extracellular signal-regulated kinase 1/2, and p38, and c-Jun N-terminal kinase) and nuclear receptor (NF)-${\kappa}B$ together with intracellular reactive oxygen species generation were required for the expression of proinflammatory cytokines in BMDMs. In addition, the rough morphotypes of M. scrofulaceum clinical strains induced higher levels of proinflammatory cytokines, MAPK and NF-${\kappa}B$ activation, and ROS production than other strains. When mice were infected with different M. scrofulaceum strains, those infected with the rough strain showed the greatest hepatosplenomegaly, granulomatous lesions, and immune cell infiltration in the lungs. Notably, the bacterial load was higher in mice infected with rough colonies than in mice infected with ATCC or smooth strains. Collectively, these data indicate that rough M. scrofulaceum induces higher inflammatory responses and virulence than ATCC or smooth strains.

• Journal of Veterinary Science
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• 제24권1호
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• pp.2.1-2.14
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• 2023

Background: Hypothermia is a crucial environmental factor that elevates the risk of cardiovascular disease, but the underlying effect is unclear. Objectives: This study examined the role of cold stress (CS) in cardiac injury and its underlying mechanisms. Methods: In this study, a chronic CS-induced myocardial injury model was used; mice were subjected to chronic CS (4℃) for three hours per day for three weeks. Results: CS could result in myocardial injury by inducing the levels of heat shock proteins 70 (HSP70), enhancing the generation of creatine phosphokinase-isoenzyme (CKMB) and malondialdehyde (MDA), increasing the contents of tumor necrosis factor-α (TNF-α), high mobility group box 1 (HMGB1) interleukin1b (IL-1β), IL-18, IL-6, and triggering the depletion of superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH). Multiple signaling pathways were activated by cold exposure, including pyroptosis-associated NOD-like receptor 3 (NLRP3)-regulated caspase-1-dependent/Gasdermin D (GSDMD), inflammation-related toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88)-mediated nuclear factor kappa B (NF-κB), and mitogen-activated protein kinase (MAPK), as well as oxidative stressinvolved thioredoxin-1/thioredoxin-interacting protein (Txnip) signaling pathways, which play a pivotal role in myocardial injury resulting from hypothermia. Conclusions: These findings provide new insights into the increased risk of cardiovascular disease at extremely low temperatures.

• 한국전자파학회논문지
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• 제21권3호
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• pp.236-244
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• 2010

본 논문에서는 기존에 제안된 일반적인 집중 소자 마이너스 군지연 회로가 설계시 사용 가능한 소자 값이 제한되어 있다는 점에 착안하여 마이너스 군지연 회로(Negative Group Delay Circuit: NGDC)를 평면 구조로 설계할 수 있는 방법에 관하여 제안한다. 몇 가지 형태의 집중 소자 회로를 해석하여 마이너스 군지연 특성을 얻을 수 있는 조건을 분석하고, 이를 수식화하여 설계에 이용할 수 있도록 하였다. 또한 전송 선로 공진기의 개념을 도입하여 집중 소자를 분산 소자로 변환할 수 있도록 하였다. 설계 예시로써, 군지연 시간이 -8 ns인 집중 소자 및 평면 구조의 1단 NGDC를 설계하여 비교하였다. 상용 주파수 대역 내에서 엄격한 평탄도 요구 조건을 만족시키는 마이너스 군지연 응답을 얻기 위하여, WCDMA(Wideband Code Division Multiple Access) 하향 대역에서 총군지연 시간이 -5.6 ns, 삽입 손실이 -0.2 dB, 대역폭이 30 MHz(2.125~2.155 GHz)이며, 해당 대역 내에서 삽입 손실 평탄도가 0.1 dB, 군지연 평탄도가 0.5 ns 이내인 평면 구조 2단 NGDC를 제작하였다. 제안하는 NGDC의 유용성을 검토하기 위하여 간단한 신호 상쇄 루프에 대한 실험을 수행하였으며, 뛰어난 신호 상쇄 효과를 얻을 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제23권8호
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• pp.1089-1095
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• 2010

Four biological candidate genes, natural resistance associated macrophage protein 1 (SLC11A1 or NRAMP), prosaposin (PSAP), interferon Gamma (IFNG), and toll-like receptor 4 (TLR4), were examined to identify single nucleotide polymorphisms (SNP) and associations of the SNP with antibody response kinetics in hens. An $F_2$ population was produced by mating $G_0$ highly inbred (<99%) males of two MHC-congenic Fayoumi lines with highly inbred Leghorn hens. The $F_2$ hens (n = 158) were injected twice with SRBC and whole, fixed Brucella abortus (BA). Blood samples were obtained before each immunization, at 7 d after primary immunization, and at several time points after secondary immunization. Minimum titers (Ymin) and the time needed to reach them (Tmin), and maximum (Ymax) titers and the time needed to reach them (Tmax), were estimated from the seven post-secondary immunization titers using a nonlinear regression model. The $F_2$ hens were genotyped for the four candidate genes by using PCR-RFLP for one SNP per gene, which identified the parental allele. General linear models were used to test associations of SNP genotypes with antibody response parameters and BW measured at 4 ages. The IFNG SNP was highly significantly (p<0.0125) associated with primary response to SRBC, Tmin to BA, Ymin to BA, and 12-week BW. The current study demonstrated that the novel IFNG promoter SNP was associated with antibody kinetics for BA and SRBC in laying hens, and also with BW, suggesting that this cytokine may play a pivotal role in the relationship between immune function and growth.

• Asian-Australasian Journal of Animal Sciences
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• 제29권1호
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• pp.16-22
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• 2016

The intestinal environment plays a critical role in maintaining swine health. Many factors such as diet, microbiota, and host intestinal immune response influence the intestinal environment. Intestinal alkaline phosphatase (IAP) is an important apical brush border enzyme that is influenced by these factors. IAP dephosphorylates bacterial lipopolysaccharides (LPS), unmethylated cytosine-guanosine dinucleotides, and flagellin, reducing bacterial toxicity and consequently regulating toll-like receptors (TLRs) activation and inflammation. It also desphosphorylates extracellular nucleotides such as uridine diphosphate and adenosine triphosphate, consequently reducing inflammation, modulating, and preserving the homeostasis of the intestinal microbiota. The apical localization of IAP on the epithelial surface reveals its role on LPS (from luminal bacteria) detoxification. As the expression of IAP is reported to be downregulated in piglets at weaning, LPS from commensal and pathogenic gram-negative bacteria could increase inflammatory processes by TLR-4 activation, increasing diarrhea events during this phase. Although some studies had reported potential IAP roles to promote gut health, investigations about exogenous IAP effects or feed additives modulating IAP expression and activity yet are necessary. However, we discussed in this paper that the critical assessment reported can suggest that exogenous IAP or feed additives that could increase its expression could show beneficial effects to reduce diarrhea events during the post weaning phase. Therefore, the main goals of this review are to discuss IAP's role in intestinal inflammatory processes and present feed additives used as growth promoters that may modulate IAP expression and activity to promote gut health in piglets.

• Journal of Microbiology and Biotechnology
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• 제19권1호
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• pp.55-64
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• 2009

A B cell-specific growth substance (BGS) was isolated from the slime layer of Bacillus licheniformis E1. Unlike LPS, the BGS was not affected by polymixin B, an inhibitor of LPS, or by TLR4, and resulted in the growth of B cells. When BALB/c mice were treated with the BGS, the B cell population was found to increase in both the bone marrow and the spleen, with a marked increase after 24 h in the bone marrow and after 48 h in the spleen. When using antibodies to B cell lineage-restricted surface molecules to analyze the B cell population changes resulting from treatment with the BGS, an increase in immature B cells ($IgM^+$ and $AA4.1^+$) and mature B cells ($IgM^+$ and $IgD^+$) was found in the bone marrow 24 h after treatment with the BGS, whereas a decrease in mature B cells and increase in $IgG^+$ B cells were found in the spleen. When the BGS and OVA antigen were injected into the peritoneal cavity of BALB/c mice, this resulted in a high OVA-specific antibody titer in the sera, similar to that induced by aluminum hydroxide. Therefore, it is anticipated that the mass production of the BGS by B. licheniformis E1 could be used for studies of B cells in immunology, and contribute to the development of a new adjuvant for vaccine manufacture.

• Asian-Australasian Journal of Animal Sciences
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• 제27권5호
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• pp.749-756
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• 2014

The present study was carried out to investigate the effects of dietary antioxidants on pro-inflammatory cytokines, heat shock protein (HSP) and antioxidant status in broiler chicks under summer conditions. A total of 162, 3-d-old broiler chicks were randomly assigned to a basal diet (CON) and the basal diet supplemented with vitamin C (200 mg/kg diet, VCD) or vitamin E (100 mg/kg, VED) until 35 day of age. All birds were exposed to summer diurnal heat stress at average daily fluctuations of temperature between $32^{\circ}C$ to $34^{\circ}C$ at day to $27^{\circ}C$ to $29^{\circ}C$ at night for the entire feeding periods. There was no significant difference in body weight, feed to gain ratio and the relative organ weight except the thymus in response to dietary vitamin C or E supplementation. However, the mRNA expression of interleukin (IL)-$1{\beta}$, IL-6, interferon (IFN)-${\gamma}$, Toll like receptor (TLR)-4 and HSP70 in the liver of birds fed diet containing vitamin C significantly (p<0.05) decreased compared with those in birds fed basal diet. Dietary vitamin E also showed a significant (p<0.05) decrease in the mRNA expression of IL-6 and HSP70 compared with a basal diet. Total antioxidant status (TAS) in serum of birds fed vitamin C supplemented diet was significantly (p<0.05) higher with than that in birds a basal diet. Lipid peroxidation in serum and liver resulted in a significant (p<0.05) decrease in response to dietary vitamin C or E supplementation. In conclusion, dietary supplementation with antioxidant vitamins, especially vitamin C resulted in a significant decrease in the mRNA expression of pro-inflammatory cytokines and HSP70, and higher antioxidant parameters than that of birds on the basal diet under summer conditions.