Systemic and mucosal immunity induced by attenuated Salmonella enterica serovar Typhimurium expressing ORF7 of porcine reproductive and respiratory syndrome virus     

Han YW  Kim SB  Rahman M  Uyangaa E  Lee BM  Kim JH  Park KI  Hong JT  Han SB  Eo SK 《Comparative immunology, microbiology and infectious diseases》2011,34(4):335-345

Oral administration of attenuated Salmonella vaccine may provide valuable advantages such as low cost, easy preparation, and safety. Attenuated Salmonella vaccines also serve as carriers of foreign antigens and immunomodulatory cytokines. Presently, an attenuated Salmonella enterica serovar Typhimurium strain was used as a carrier for open reading frame 7 (ORF7) protein of porcine reproductive and respiratory syndrome virus (PRRSV), a swine pathogen of significant global economic importance. Initially, an attenuated S. enterica serovar Typhimurium expressing ORF7 gene derived from PRRSV Korean isolate was constructed. Following oral administration of a single dose of the attenuated Salmonella vaccine expressing PRRSV ORF7, humoral and cell-mediated immune responses specific for ORF7 were induced at both systemic and mucosal sites including spleen, mesenteric lymph node, Peyer's patch, and laminar propria, as evaluated by determining serum ORF7-specific IgG and mucosal IgA responses, as well as Th1- and Th2-type cytokine production from antigen-stimulated T cells. The induced humoral responses were sustained for at least 12 weeks post-immunization. In particular, the immunized mice displayed immune responses to both the foreign ORF7 antigen and Salmonella itself. The results indicate the value of attenuated S. enterica serovar Typhimurium as an oral carrier of PRRSV antigenic proteins to induce effective systemic and mucosal immunity.  相似文献   

Omega-3 Fatty Acids Upregulate SIRT1/3, Activate PGC-1α via Deacetylation,and Induce Nrf1 Production in 5/6 Nephrectomy Rat Model     

Sung Hyun Son  Su Mi Lee  Mi Hwa Lee  Young Ki Son  Seong Eun Kim  Won Suk An 《Marine drugs》2021,19(4)

Mitochondrial dysfunction contributes to the pathogenesis of kidney injury related with cardiovascular disease. Peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) protects renal tubular cells by upregulating nuclear factor erythroid 2-related factor 2 (Nrf2). AMP-activated protein kinase (pAMPK)-mediated phosphorylation and sirtuin 1/3 (SIRT1/3)-mediated deacetylation are required for PGC-1α activation. In the present study, we aimed to investigate whether omega-3 fatty acids (FAs) regulate the expression of mediators of mitochondrial biogenesis in 5/6 nephrectomy (Nx) rats. Male Sprague-Dawley rats were assigned to the following groups: sham control, Nx, and Nx treated with omega-3 FA. The expression of PGC-1α, phosphorylated PGC-1α (pPGC-1α), acetylated PGC-1α, and factors related to mitochondrial biogenesis was examined through Western blot analysis. Compared to the control group, the expression of PGC-1α, pAMPK, SIRT1/3, Nrf1, mTOR, and Nrf2 was significantly downregulated, and that of Keap 1, acetylated PGC-1α, and FoxO1/3, was significantly upregulated in the Nx group. These changes in protein expression were rescued in the omega-3 FA group. However, the expression of pPGC-1α was similar among the three groups. Omega-3 FAs may involve mitochondrial biogenesis by upregulating Nrf1 and Nrf2. This protective mechanism might be attributed to the increased expression and deacetylation of PGC-1α, which was triggered by SIRT1/3.  相似文献   

Accuracy of sonographic diagnosis of pneumoperitoneum using the enhanced peritoneal stripe sign in beagle dogs     

Song Yeon Kim  Ki Tae Park  Seong Chan Yeon  Hee Chun Lee 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(2):195-198

The objective of this study was to evaluate the feasibility and accuracy of estimating the smallest amount of abdominal free gas detectible in a large population of beagles by ultrasonography. Healthy dogs were randomly divided into three groups: group A that received 0.1 mL of air injected into the peritoneal cavity, group B that received 0.2 mL of air injected into the peritoneal cavity, and group C that received 0.5 mL of intraperitoneal air. Randomly, some dogs in each group did not receive air injection for the negative control. All ultrasonographic procedures were performed by individuals blinded to group assignments and the presence of intraperitoneal air. The minimum volume of consistently detectable air with good accuracy and reliability was 0.2 mL. Results of the study demonstrated that the enhanced peritoneal stripe sign (EPSS) can verify cases of pneumoperitoneum if more than 0.2 mL of intra-abdominal free gas is present The EPSS is a reliable and specific ultrasonographic characteristic for diagnosing pneumoperitoneum in dogs.  相似文献   

基于样本熵的高水头混流式水轮机稳定性分析     

朱国俊  陈旻甲  冯建军  刘可然  罗兴锜 《农业机械学报》2021,52(7):134-140，101

机组的压力脉动是表征水轮机稳定性的主要参数之一,但仅基于压力脉动幅值判定水轮机的稳定性存在一定的局限性。采用多通道压力脉动同步采集系统同步采集某高水头混流式水轮机部分负荷下多部位压力脉动数据,然后综合互相关分析和互补集合经验模态分解(CEEMD)方法提取各压力脉动信号的主分量,对各压力脉动信号的主分量数据进行样本熵计算,获得不同测点在运行范围内的样本熵分布规律。结果表明：在部分负荷下,尾水管内部的空腔涡带仍然是影响高水头混流式水轮机稳定性的主要因素;可根据水轮机各部位压力脉动信号主分量的频率信息推断水轮机内部水力不稳定源的类型;关键测点处压力脉动幅值分布规律与样本熵分布规律的对比表明,压力脉动信号主分量的样本熵变化趋势能够反映水轮机内部流动状态的变化趋势。  相似文献   

Properties of polyacrylonitrile/single wall carbon nanotube composite films prepared in nitric acid     

Seong Hoon Kim  Byung Gil Min  Sang Cheol Lee 《Fibers and Polymers》2005,6(2):108-112

Nanocomposite films were prepared by casting the solution of polyacrylonitrile (PAN) and single wall nanotube (SWNT) in nitric acid subsequent to sonication. Even though SWNT shows good dispersion visually, the reinforcing effect was not satisfactory. The G-band Raman spectra of the drawn film clearly demonstrated that SWNTs in the film are well-oriented along the drawing axis of the film. The electrical resistivity of the film prepared using nitric acid was lower than that of the film using DMF. Thus, nitric acid is presumably more effective in dispersing nanotubes than DMF.  相似文献   

Organic solvent absorption characteristics of split-type microfiber fabrics     

Lee  Kwang Ju  Kim  Seong Hun  Oh  Kyung Wha 《Fibers and Polymers》2004,5(4):280-288

Split-type nylon/polyester microfiber and polyester microfiber fabrics possess drapeability, softness, bulkiness, and smoothness, so that they can be applied in various industrial fields. In particular, these fabrics are able to absorb various organic solvents, and can be used as clean room materials. To investigate the chemical affinity between solvents and the compositional materials of these fabrics, the contact angle of thermally pressed film fabrics was measured with different solvents. The thermally pressed nylon/polyester fabric films showed a chemical attraction to formamide. The sorption properties of the microfiber fabrics were investigated using a real time testing device, and these tests showed that the sorption behavior was more influenced by the structure of the fibrous assembly than by any chemical attraction. The effect of the fabric density, specific weight, and sample structure on the sorption capacity and rate was examined for various organic solvents. The sorption capacity was influenced by the density and the specific weight of the fibrous assembly, and knitted fabric showed a higher sorption capacity than woven fabric. However, the sorption rate was less affected in lower viscosity solvents. On applying Poiseuille’s Law, the lower viscosity solvents showed higher initial sorption rates, and more easily penetrated into the fibrous assembly.  相似文献   

Relationship between fiber orientation distribution function and mechanical anisotropy of thermally point-bonded nonwovens     

Han?Seong?KimEmail author 《Fibers and Polymers》2004,5(3):177-181

Current efforts to establish links between geometrical features and mechanical performance of nonwoven fabrics in general, and of point-bonded (spot-bonded) nonwovens in particular has been made using the measurements of Fiber Orientation Distribution Function (ODF) and tensile modulus which occurs during controlled-deformation experiments. Image analysis technique (using the Fast Fourier Transform) was used to quantify the fiber orientation distribution. The results suggest that, within a typical window of processing conditions, the fiber orientation has a significant influence on the anisotropical behavior of nonwoven. The data also suggest that mechanical anisotropy of thermally point-bonded nonwovens is likely to be governed by different load transfer mechanism according to the applied macroscopic tensile direction.  相似文献   

Orthotropic theory for the prediction of mechanical performance in thermally point-bonded nonwovens     

Han?Seong?KimEmail author 《Fibers and Polymers》2004,5(2):139-144

The orthotropic theory is applied for the nonwoven fabrics that have a preferred orientation direction, the case if the structure is not isotropic. The polynomial regression analysis is employed to allow the attainment of more statistically meaningful information. A functional form based on the transformation rule is developed for the orthotropic approach. The predictions thus obtained are seen to be in excellent agreements with experimental data and the resulting compliances exhibit meaningful relationships for the processing conditions. The compatibility of the compliances from tensile and shear analyses has been explored prior to a practical application of the four compliances defining the in-plane strain-stress field.  相似文献   

Chemical modification of isotactic polypropylene by melt blending     

Jun?Young?Kim  Eun?Su?Seo  Dae?Soon?Park  Kwang?Min?Park  Seong?Wook?Kang  Chang?Hyung?Lee  Seong?Hun?KimEmail author 《Fibers and Polymers》2003,4(3):107-113

The branched polypropylene (b-PP) was prepared by melt blending process with initiator, antioxidant, and functional monomers to improve the melt strength through the melt grafting. The melt flow index (MFI) of theb-PP was increased with increasing the initiator content. On the introduction of the alkylamine as the branching agents the MFI of theb-PP was increased, while that of theb-PP with the pentaerythritol triacrylate (PT) was decreased. It may be caused by the chain scission of thei-PP backbone due to the reduced thermal stability of thei-PP on the melt blending. The MFI of theb-PP without the antioxidant was increased due to the chain scission occurred during the melt processing, while on the introduction of the antioxidant, the MFI of theb-PP was decreased. The crystallization temperature of theb-PP was higher than that of PP, which was attributed to the branched chain structure. It was found that the PT was the most effective functional monomers for enhancing the melt properties of theb-PP.  相似文献   

Morphology and properties of polyacrylonitrile/single wall carbon nanotube composite films     

Seong?Hoon?Kim  Byung?Ghyl?MinEmail author  Sang?Cheol?Lee  Sung?Bum?Park  Tae?Dong?Lee  Min?Park  Satish?Kumar 《Fibers and Polymers》2004,5(3):198-203

Composite films were prepared by casting the solution of polyacrylonitrile (PAN) and single wall nanotube (SWNT) in DMF subsequent to sonication. The SWNTs in the films are well dispersed as ropes with 20–30 nm thickness. Moreover, AFM surface image of the composite film displays an interwoven fibrous structure of nanotubes which may give rise to conductive passways and lead to high conductivity. The polarized Raman spectroscopy is an ideal characterization technique for identification and the orientation study of SWNT. The well-defined G-peak intensity at 1580 cm⁻¹ shows a dependency on the draw ratio under cross-Nicol. The degree of nanotube orientation in the drawn film was measurable from the sine curve obtained by rotating the drawn film on the plane of cross-Nicol of polarized Raman microscope. The threshold loading of SWNT for electrical conductivity in PAN is found to be lower than 1 wt% in the composite film. The electrical conductivity of the SWNT/PAN composite film decreased with increasing of draw ratio due to the collapse of the interwoven fibrous network of the nanotubes with uniaxial orientation.  相似文献