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31.
Actinobacillus pleuropneumoniae is an infective agent that leads to porcine pleuropneumonia, a disease that causes severe economic losses in the swine industry. Based on the fact that the respiratory tract is the primary site for bacterial infection, it has been suggested that bacterial exclusion in the respiratory tract through mucosal immune induction is the most effective disease prevention strategy. ApxIIA is a vaccine candidate against A. pleuropneumoniae infection, and fragment #5 (aa. 439–801) of ApxIIA contains the major epitopes for effective vaccination. In this study, we used mice to verify the efficacy of intranasal immunization with fragment #5 in the induction of protective immunity against nasal challenge with A. pleuropneumoniae and compared its efficacy with that of subcutaneous immunization. Intranasal immunization of the fragment induced significantly higher systemic and mucosal immune responses measured at the levels of antigen-specific antibodies, cytokine-secreting cells after antigen exposure, and antigen-specific lymphocyte proliferation. Intranasal immunization not only efficiently inhibited the bacterial colonization in respiratory organs, but also prevented alveolar tissue damage in infectious condition similar to that of a contaminated pig. Moreover, intranasal immunization with fragment #5 provided acquired protective immunity against intranasal challenge with A. pleuropneumoniae serotype 2. In addition, it conferred cross-protection against serotype 5, a heterologous pathogen that causes severe disease by ApxI and ApxII secretion. Collectively, intranasal immunization with fragment #5 of ApxIIA can be considered an efficient protective immunization procedure against A. pleuropneumoniae infection.  相似文献   
32.
Sargassum muticum (S. muticum) is a brown edible alga and widely distributed in Korea. This report was designed to evaluate the anti-inflammatory properties of apo-9′-fucoxanthinone (APO-9′) isolated from S. muticum on pro-inflammatory cytokine production. S. muticum extract (SME) exhibited significant inhibitory effects on pro-inflammatory cytokine production in bone marrow-derived macrophages (BMDMs) and dendritic cells (BMDCs). APO-9′ pre-treatment in the CpG DNA-stimulated BMDMs and BMDCs showed a strong dose-dependent inhibitory effect on interleukin (IL)-12 p40, IL-6 and tumor necrosis factor (TNF)-α production with IC50 values ranging from 5.31 to 13.79. It exhibited a strong inhibitory effect on the phosphorylation of ERK1/2 and on activator protein (AP)-1 reporter activity. APO-9′ pre-treatment exhibited significant inhibition of CpG DNA-induced production of inducible nitric oxide synthase. Taken together, these data suggest that SME and APO-9′ have a significant anti-inflammatory property and warrant further studies concerning the potentials of SME and APO-9′ for medicinal use.  相似文献   
33.
Phytochemical levels in fruits and vegetables can be affected by several postharvest factors. In the present study, the effect of electron-beam (E-beam) irradiation was studied on grapefruit bioactive compounds. 'Rio Red' and 'Marsh White' grapefruits were irradiated with E-beam at 0, 1.0, 2.5, 5.0, and 10.0 kGy. Changes of various bioactive compounds, such as vitamin C, flavonoids, carotenoids, furocoumarins, and limonoids, were measured. The acidity decreased slightly with an increasing E-beam dose, whereas the total soluble solids were increased. Irradiation did not affect the vitamin C content at 1 kGy; however, doses beyond 1 kGy significantly reduced the vitamin C content. Lycopene and beta-carotene did not change significantly from the irradiation. Lycopene levels decreased as the E-beam dose increased, while the beta-carotene content slightly increased. Dihydroxybergamottin levels exhibited a decreasing trend, while the bergamottin content did not change. Naringin, a major flavonoid of grapefruit, showed a significant increase over the control at 10 kGy in both 'Rio Red' and 'Marsh White'. Nomilin continued to decrease with an increasing dose of E-beam irradiation, while limonin levels remained the same at all of the doses. Low-dose E-beam irradiation has very little effect on the bioactive compounds and offers a safe alternative to existing postharvest treatments for the disinfection and decontamination of grapefruits.  相似文献   
34.
Astrocytes perform neuron-supportive tasks, repair and scarring process in the central nervous system. In this study, we observed glial fibrillary acidic protein (GFAP), a marker for astrocytes, immunoreactivity in the dentate gyrus and hippocampus proper (CA1-3 region) of adult (2-3 years of age) and aged (10-12 years of age) dogs. In the adult group, GFAP immunoreactive astrocytes were distributed in all layers of the dentate gyrus and CA1-3 region, except in the stratum pyramidale of the CA1-3 region. In the aged group, GFAP immunoreactivity decreased markedly in the molecular layer of the dentate gyrus. However, GFAP immunoreactivity in the CA1-3 region increased in all layers, and the cytoplasm of GFAP immunoreactive astrocytes was hypertrophied. GFAP protein levels in the aged dentate gyrus decreased; however, GFAP levels in the CA1-3 region increased. These results suggest that the morphology of astrocytes and GFAP protein levels in the hippocampal dentate gyrus and CA1 region are changed, respectively, with age.  相似文献   
35.
The establishment of pregnancy is a complex process that requires a well-coordinated interaction between the implanting conceptus and the maternal uterus. In pigs, the conceptus undergoes dramatic morphological and functional changes at the time of implantation and introduces various factors, including estrogens and cytokines,interleukin-1β2(IL1 B2), interferon-γ(IFNG), and IFN-δ(IFND), into the uterine lumen. In response to ovarian steroid hormones and conceptus-derived factors, the uterine endometrium becomes receptive to the implanting conceptus by changing its expression of cell adhesion molecules, secretory activity, and immune response. Conceptus-derived estrogens act as a signal for maternal recognition of pregnancy by changing the direction of prostaglandin(PG) F2αfrom the uterine vasculature to the uterine lumen. Estrogens also induce the expression of many endometrial genes,including genes related to growth factors, the synthesis and transport of PGs, and immunity. IL1 B2, a pro-inflammatory cytokine, is produced by the elongating conceptus. The direct effect of IL1 B2 on endometrial function is not fully understood. IL1 B activates the expression of endometrial genes, including the genes involved in IL1 B signaling and PG synthesis and transport. In addition, estrogen or IL1 B stimulates endometrial expression of IFN signaling molecules,suggesting that estrogen and IL1 B act cooperatively in priming the endometrial function of conceptus-produced IFNG and IFND that, in turn, modulate endometrial immune response during early pregnancy. This review addresses information about maternal-conceptus interactions with respect to endometrial gene expression in response to conceptus-derived factors, focusing on the roles of estrogen and IL1 B during early pregnancy in pigs.  相似文献   
36.
Campylobacter jejuni is one of the major causative pathogens of outbreaks or sporadic cases of diarrhoeal diseases worldwide. In this study, we compared the phenotypic and genetic characteristics of C. jejuni isolates of human and food‐producing animal origins in Korea and examined the genetic relatedness between these two groups of isolates. Regardless of isolation source, all C. jejuni isolates harboured four virulence genes, cadF, cdtB, ciaB and racR, whereas the wlaN and virB11 genes were more frequently observed in human isolates. Antimicrobial susceptibility testing showed that the majority of C. jejuni isolates displayed high‐level resistance to fluoroquinolone (95.2%) or tetracycline (76.2%) antibiotics, and 12.4% of isolates exhibited multidrug resistance (more than three classes of antibiotics tested). Pulsed‐field gel electrophoresis (PFGE) of all Campylobacter isolates revealed 51 different SmaI‐PFGE patterns and six major clusters containing both human and animal isolates. These results indicate that genetically diverse strains of C. jejuni with antimicrobial drug‐resistance and virulence properties have prevailed in Incheon. Nevertheless, some particular populations continue to circulate within the community, providing the evidence for an epidemiological link of C. jejuni infections between humans and food‐producing animals. Therefore, the continued monitoring and surveillance of C. jejuni isolates of human and food‐producing animal origins are required for public health and food safety.  相似文献   
37.
A quaternary combinatorial masking strategy was used in conjunction with photolithography to generate compositionally diverse thin-film phosphor libraries containing 1024 different compositions on substrates 2.5 centimeters square. A parallel imaging system and scanning spectrophotometer were used to identify and characterize compositions in the library with interesting luminescent behavior. Optimal compositions were identified with the use of gradient libraries, in which the stoichiometry of a material was varied continuously. This process led to the identification of an efficient blue photoluminescent composite material, Gd3Ga5O12/SiO2. Experimental evidence suggests that luminescence in this material may arise from interfacial effects between SiO2 and Gd3Ga5O12.  相似文献   
38.
A series of 1-aryl-1-(1H-1,2,4-triazol-1-yl)alkyl-1-silacyclopentanes has been synthesized by four-step reactions starting from 1-chloroalkyltrichlorosilane and tested for fungicidal activities in vitro for ten fungi and in vivo for four fungi occurring in rice, cucumber, tomato etc. Biological activities of the title compounds are strongly dependent upon the p-substituent on the phenyl group in the following order: F>Cl>Ph>OEt>H. Especially, 1-p-fluorophenyl-1-[1-(1H-1,2,4-triazol-1-yl)alkyl]-1-silacyclopentanes (alkyl=methyl or ethyl) showed significant fungicidal activity with a broad spectrum comparable to flusilazole in in-vivo assay. © 1998 SCI.  相似文献   
39.
Discovery of Helicobacter (H.) pylori has led to a fundamental change in our understanding of gastric diseases in humans. Previous studies have found various Helicobacter spp. in dogs and cats, and pets have been questioned as a zoonotic carrier. The present study surveyed the Helicobacter infections and investigated the presence of H. felis and H. pylori infections in domestic and feral cats in Korea. Sixty-four domestic cats and 101 feral cats were selected from an animal shelter. Saliva and feces were evaluated by Helicobacter genus-specific polymerase chain reaction (PCR). Genus-specific PCR positive samples were further evaluated for H. felis and H. pylori using specific primer pairs. Thirty-six of 64 (56.3%) samples from domestic cats and 92 of 101 (91.1%) samples from feral cats were PCR positive; the positive rate of feces samples was higher than that of saliva samples in both groups. H. felis and H. pylori species-specific PCR was uniformly negative. The prevalence of Helicobacter spp. in feral cats was approximately two-fold higher than that of domestic cats. The fecal-oral route may be more a common transmission route not only between cats but also in humans.  相似文献   
40.
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