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91.
92.
The immune-stimulating activities of Bordetella bronchiseptica antigens containing dermonecrotoxin (BBD) loaded in chitosan microspheres (CMs) have already been reported in vitro and in vivo with a mouse alveolar macrophage cell line (RAW264.7) and mice. Therefore, this study attempted to demonstrate the successful induction of mucosal immune responses after the intranasal administration of BBD loaded in CMs (BBD-CMs) in colostrum-deprived pigs. The BBD was introduced to the CMs using an ionic gelation process involving tripolyphosphate (TPP). Colostrum-deprived pigs were then directly immunized through intranasal administration of the BBD-CMs. A challenge with a field isolate of B. bronchiseptica was performed ten days following the final immunization. The BBD-specific IgG and IgA titers, evident in the nasal wash and serum from the vaccinated pigs, increased with time (p<0.05). Following the challenge, the clinical signs of infection were about 6-fold lower in the vaccinated pigs compared with the nonvaccinated pigs. The grades for gross morphological changes in the turbinate bones from the vaccinated pigs were also significantly lower than the grades recorded for the nonvaccinated pigs (p<0.001). Therefore, the mucosal and systemic immune responses induced in the current study would seem to indicate that the intranasal administration of BBD-CMs may be an effective vaccine against atrophic rhinitis in pigs.  相似文献   
93.
YKL-40, a chitinase-3-like protein 1 (CHI3L1) or human cartilage glycoprotein 39 (HC gp-39), is expressed and secreted by various cell-types including macrophages, chondrocytes, fibroblast-like synovial cells and vascular smooth muscle cells. Its biological function is not well elucidated, but it is speculated to have some connection with inflammatory reactions and autoimmune diseases. Although having important biological roles in autoimmunity, there were only attempts to elucidate relationships of YKL-40 with a single or couple of diseases in the literature. Therefore, in order to analyze the relationship between YKL-40 and the overall diseases, we reviewed 51 articles that discussed the association of YKL-40 with rheumatoid arthritis, psoriasis, systemic lupus erythematosus, Behçet disease and inflammatory bowel disease. Several studies showed that YKL-40 could be assumed as a marker for disease diagnosis, prognosis, disease activity and severity. It is also shown to be involved in response to disease treatment. However, other studies showed controversial results particularly in the case of Behçet disease activity. Therefore, further studies are needed to elucidate the exact role of YKL-40 in autoimmunity and to investigate its potential in therapeutics.  相似文献   
94.
The CC chemokine receptor 7 (CCR7) and cognate CCR7 ligands, CCL19 and CCL21, help establish microenvironments in lymphoid tissue that can facilitate encounters between naive T cells and mature dendritic cells (DCs). This study was conducted to determine if CCR7 ligands can augment the immunogenicity of a DNA vaccine that expresses glycoprotein B (gB) of the pseudorabies virus (PrV). The genetic co-transfer of CCR7 ligands along with a PrV DNA vaccine increased the levels of serum PrV-specific immunoglobulin (Ig) G by 2- to 2.5-fold. In addition, the level of PrV-specific IgG2a isotype was significantly enhanced by co-injection of CCR7 ligand DNA, which indicates that CCR7 ligand biases the humoral immunity toward the Th1-type pattern. The co-injection of CCR7 ligand DNA consistently enhanced the level of Th1-type cytokines (IL-2 and IFN-gamma) produced by stimulated immune cells when compared with a group that was vaccinated with the PrV DNA vaccine. Also, the genetic co-transfer of CCR7 ligand DNAs with PrV DNA vaccine provided prolonged survival against a virulent challenge by PrV. Moreover, the co-administration of CCR7 ligand DNA increased the number of mature DCs into the secondary lymphoid tissues, which appeared to enhance the proliferation of PrV-immune CD4(+) T cells. Taken together, these findings indicate that CCR7 ligands are an attractive adjuvant for a PrV DNA vaccine that can offer protective immunity against the PrV.  相似文献   
95.
Efficient target gene delivery into eukaryotic cells is important for biotechnological research and gene therapy. Gene delivery based on proteins, including histones, has recently emerged as a powerful non-viral DNA transfer technique. Here, we investigated the potential use of a recombinant mussel adhesive protein, hybrid fp-151, as a gene delivery material, in view of its similar basic amino acid composition to histone proteins, and cost-effective and high-level production in Escherichia coli. After confirming DNA binding affinity, we transfected mammalian cells (human 293T and mouse NIH/3T3) with foreign genes using hybrid fp-151 as the gene delivery carrier. Hybrid fp-151 displayed comparable transfection efficiency in both mammalian cell lines, compared to the widely used transfection agent, Lipofectamine 2000. Our results indicate that this mussel adhesive protein may be used as a potential protein-based gene-transfer mediator.  相似文献   
96.
ABSTRACT: BACKGROUND: The objective of this study was to identify prognostic factors for survival in patients with primary diffuse large B-cell lymphoma (DLBCL) of the adrenal gland. METHODS: Thirty one patients diagnosed with primary adrenal DLBCL from 14 Korean institutions and treated with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone) were analyzed. RESULTS: Complete remission (CR) and overall response rate after R-CHOP chemotherapy were 54.8% and 87.0%. The 2-year estimates of overall survival (OS) and progression-free survival (PFS) were 68.3% and 51.1%. In patients achieving CR, significant prolongations of OS (P = 0.029) and PFS (P = 0.005) were observed. Ann Arbor stage had no influence on OS. There was no significant difference in OS between patients with unilateral involvement of adrenal gland and those with bilateral involvement. When staging was modified to include bilateral adrenal involvement as one extranodal site, early stage (I or II) significantly correlated with longer OS (P = 0.021) and PFS (P <0.001). CONCLUSIONS: Contrary to prior reports, our data suggests that outcomes of primary adrenal DLBCL are encouraging using a regimen of R-CHOP, and that achieving CR after R-CHOP is predictive of survival. Likewise, our modified staging system may have prognostic value.  相似文献   
97.
98.
In vitro cellular senescence of human diploid fibroblast has been a good model for aging research, which shows similar phenotypes to in vivo aging. Gene expression profiling would provide an insight to understand the mechanism of senescence. Using cDNA microarray containing 384 known genes, we compared the expression profiles of three different types of aging models: replicative senescence, fibroblasts from progeria or from elderly donor. Although all of them showed senescence phenotypes, distinct sets of genes were altered in each group. Pairwise plots or cluster analysis of activation fold of gene expression revealed closer relationships between fibroblasts from progeria or from old individual, but not between replicative senescence fibroblasts and either models. Differential expression pattern of several genes were confirmed by RT-PCR. We suggest that the replicative senescence model might behave differently to other types of aging models due to the distinct gene expression.  相似文献   
99.
Kim EK  Jang WH  Ko JH  Kang JS  Noh MJ  Yoo OJ 《Journal of bacteriology》2001,183(20):5937-5941
A lipase gene, lipK, and a lipase modulator gene, limK, of Pseudomonas sp. strain KFCC 10818 have been cloned, sequenced, and expressed in Escherichia coli. The limK gene is located immediately downstream of the lipK gene. Enzymatically active lipase was produced only in the presence of the limK gene. The effect of the lipase modulator LimK on the expression of active lipase was similar to those of the Pseudomonas subfamily I.1 and I.2 lipase-specific foldases (Lifs). The deduced amino acid sequence of LimK shares low homology (17 to 19%) with the known Pseudomonas Lifs, suggesting that Pseudomonas sp. strain KFCC 10818 is only distantly related to the subfamily I.1 and I.2 Pseudomonas species. Surprisingly, a lipase variant that does not require LimK for its correct folding was isolated in the study to investigate the functional interaction between LipK and LimK. When expressed in the absence of LimK, the P112Q variant of LipK formed an active enzyme and displayed 63% of the activity of wild-type LipK expressed in the presence of LimK. These results suggest that the Pro(112) residue of LipK is involved in a key step of lipase folding. We expect that the novel finding of this study may contribute to future research on efficient expression or refolding of industrially important lipases and on the mechanism of lipase folding.  相似文献   
100.
The Rkp1/Cpc2, a fission yeast RACK1 homolog, interacted with Pck2, one of the known PKC homologs, in vivo and in vitro. The rkp1-deletion mutants (Deltarkp1) are elongated and the pck2-deletion mutant (Deltapck2) showed abnormal morphology. The double-deletion mutant (Deltarkp1Deltapck2) showed more aberrant cell shapes and was sensitive to high salt concentration. Both Deltarkp1 and Deltapck2 cells were sensitive to latrunculin B (Lat B) which inhibits actin polymerization. The cells expressing the human RACK1 homolog complemented the latrunculin B sensitivity of Deltarkp1 indicating that human RACK1 is a functional homolog of Rkp1/Cpc2. We propose that Rkp1/Cpc2 may function as a receptor for Pck2 in the regulation of actin cytoskeleton organization during cell wall synthesis and morphogenesis of Schizosaccharomyces pombe.  相似文献   
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