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21.
Allergic inflammation involves the mobilization and trafficking of eosinophils to sites of inflammation. Galectin-3 (Gal-3) has been shown to play a critical role in eosinophil recruitment and airway allergic inflammation in vivo. The role played by Gal-3 in human eosinophil trafficking was investigated. Eosinophils from allergic donors expressed elevated levels of Gal-3 and demonstrated significantly increased rolling and firm adhesion on immobilized VCAM-1 and, more surprisingly, on Gal-3 under conditions of flow. Inhibition studies with specific mAbs as well as lactose demonstrated that: 1) eosinophil-expressed Gal-3 mediates rolling and adhesion on VCAM-1; 2) alpha(4) integrin mediates eosinophil rolling on immobilized Gal-3; and 3) eosinophil-expressed Gal-3 interacts with immobilized Gal-3 through the carbohydrate recognition domain of Gal-3 during eosinophil trafficking. These findings were further confirmed using inflamed endothelial cells. Interestingly, Gal-3 was found to bind to alpha(4) integrin by ELISA, and the two molecules exhibited colocalized expression on the cell surface of eosinophils from allergic donors. These findings suggest that Gal-3 functions as a cell surface adhesion molecule to support eosinophil rolling and adhesion under conditions of flow.  相似文献   
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During orthodontic treatments, applied mechanical forces create strain and result in tooth movement through the alveolar bone. This response to mechanical strain is a fundamental biological reaction. The present study evaluated the effect of equiaxial strain within the range of orthodontic forces on the osteogenic differentiation of human dental pulp stem cells (hDPSCs). Following isolation and culture of hDPSCs, 3rd passage cells were transferred on a silicone membrane covered with collagen. Cell adhesion to the membrane was evaluated under scanning electron microscope (SEM). Cells were divided into three groups: the first group was placed in a conventional culture medium, transferred to an equiaxial stretching device (3% strain for 2 weeks). The positive control was placed in an osteogenic medium with no mechanical strain. The negative control group was placed in the conventional culture medium with no mechanical strain either. Study groups were evaluated for expression of osteogenic markers (Alkaline phosphatase and Osteopontin) with immunofluorescence and real time PCR. SEM images revealed optimal adhesion of cells to the silicone membrane. Immunofluorescence study demonstrated that osteocalcin expression occurred after 2 weeks in the two groups under mechanical and chemical signals. After application of equiaxial strain, level of expression of osteogenic markers was significantly higher than in the negative and positive control groups. Based on the study results, static equiaxial strain which mimics the types of orthodontic forces can result in differentiation of hDPSCs to osteoblasts. The results obtained may be used in cell therapy and tissue engineering.  相似文献   
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A method for analysis of volatile organic compounds (VOCs) from microbial cultures was established using proton transfer reaction-mass spectrometry (PTR-MS). A newly developed sampling system was coupled to a PTR-MS instrument to allow on-line monitoring of VOCs in the dynamic headspaces of microbial cultures. The novel PTR-MS method was evaluated for four reference organisms: Escherichia coli, Shigella flexneri, Salmonella enterica, and Candida tropicalis. Headspace VOCs in sampling bottles containing actively growing cultures and uninoculated culture medium controls were sequentially analyzed by PTR-MS. Characteristic marker ions were found for certain microbial cultures: C. tropicalis could be identified by several unique markers compared with the other three organisms, and E. coli and S. enterica were distinguishable from each other and from S. flexneri by specific marker ions, demonstrating the potential of this method to differentiate between even closely related microorganisms. Although the temporal profiles of some VOCs were similar to the growth dynamics of the microbial cultures, most VOCs showed a different temporal profile, characterized by constant or decreasing VOC levels or by single or multiple peaks over 24 h of incubation. These findings strongly indicate that the temporal evolution of VOC emissions during growth must be considered if characterization or differentiation based on microbial VOC emissions is attempted. Our study may help to establish the analysis of VOCs by on-line PTR-MS as a routine method in microbiology and as a tool for monitoring environmental and biotechnological processes.  相似文献   
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This study investigated the effect of dietary supplementation of probiotic Pedicoccus acidilactici and nucleotide (separately or combined) on growth performance, intestinal microbiota, hemato-immunological parameters, and immunity response in goldfish (Carassius auratus). Fish (average weight 5–6 g) were acclimatized and divided into eight experimental diets supplemented with P. acidilactici of different concentrations (0.1, 0.2, and 0.3% diet) and nucleotides (0 and 0.5% diet) for 6 months. Fish fed with experimental diets showed significant differences in terms of final weight, weight gain, feed conversion ratio, daily growth rate, and condition factor when compared to control diet (P < 0.05). Fish fed with probiotic (0.3%) separately and combined with nucleotide (0.5%) had highest RBC and WBC when compared to other diets (P < 0.05), while the highest values for Hb and Hct as well as total protein, glucose, albumin, and globulin were observed in probiotic (0.2%) and nucleotide (0.5%) combined diet. Serum lysozyme and anti-protease activities were significantly higher in probiotic (0.1 and 0.2%) and nucleotide (0.5%) combined diets. Similarly, these two diets combined showed the highest colonization of P. acidilactici when compared to other diets. In conclusion, combined dietary probiotic and nucleotide improve the growth performance, hemato-biochemical parameters, and intestine growth in C. auratus.  相似文献   
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Onconase is a distinctive RNase due to a prominent feature that enables this protein to exhibit selective toxicity against cancer cells. Therefore, in this  相似文献   
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Association of the neurotransmitter serotonin (5-HT) with the pathogenesis of allergic asthma is well recognized and its role as a chemoattractant for eosinophils (Eos) in vitro and in vivo has been previously demonstrated. Here we have examined the regulation of 5-HT-induced human and murine Eos trafficking and migration at a cellular and molecular level. Eos from allergic donors and bone marrow-derived murine Eos (BM-Eos) were found to predominantly express the 5-HT2A receptor. Exposure to 5-HT or 2,5-dimethoxy-4-iodoamphetamine (DOI), a 5-HT2A/C selective agonist, induced rolling of human Eos and AML14.3D10 human Eos-like cells on vascular cell adhesion molecule (VCAM)-1 under conditions of flow in vitro coupled with distinct cytoskeletal and cell shape changes as well as phosphorylation of MAPK. Blockade of 5-HT2A or of ROCK MAPK, PI3K, PKC and calmodulin, but not Gαi-proteins, with specific inhibitors inhibited DOI-induced rolling, actin polymerization and changes in morphology of VCAM-1-adherent AML14.3D10 cells. More extensive studies with murine BM-Eos demonstrated the role of 5-HT in promoting rolling in vivo within inflamed post-capillary venules of the mouse cremaster microcirculation and confirmed that down-stream signaling of 5-HT2A activation involves ROCK, MAPK, PI3K, PKC and calmodulin similar to AML14.3D10 cells. DOI-induced migration of BM-Eos is also dependent on these signaling molecules and requires Ca2+. Further, activation of 5-HT2A with DOI led to an increase in intracellular Ca2+ levels in murine BM-Eos. Overall, these data demonstrate that 5-HT (or DOI)/5-HT2A interaction regulates Eos trafficking and migration by promoting actin polymerization associated with changes in cell shape/morphology that favor cellular trafficking and recruitment via activation of specific intracellular signaling molecules (ROCK, MAPK, PI3K and the PKC-calmodulin pathway).  相似文献   
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The limited treatment option for recurrent prostate cancer and the eventual resistance to conventional chemotherapy drugs has fueled continued interest in finding new anti‐neoplastic agents of natural product origin. We previously reported anti‐proliferative activity of deoxypodophyllotoxin (DPT) on human prostate cancer cells. Using the PC‐3 cell model of human prostate cancer, the present study reveals that DPT induced apoptosis via a caspase‐3‐dependent pathway that is activated due to dysregulated mitochondrial function. DPT‐treated cells showed accumulation of the reactive oxygen species (ROS), intracellular Ca surge, increased mitochondrial membrane potential (MMP, ΔΨm), Bax protein translocation to mitochondria and cytochrome c release to the cytoplasm. This resulted in caspase‐3 activation, which in turn induced apoptosis. The antioxidant N‐acetylcysteine (NAC) reduced ROS accumulation, MMP and Ca surge, on the other hand the Ca2+ chelator BAPTA inhibited the Ca overload and MMP without affecting the increase of ROS, indicating that the generation of ROS occurred prior to Ca2+ flux. This suggested that both ROS and Ca signaling play roles in the increased MMP via Ca‐dependent and/or ‐independent mechanisms, since ΔΨm elevation was reversed by NAC and BAPTA. This study provides the first evidence for the involvement of both ROS‐ and Ca‐activated signals in the disruption of mitochondrial homeostasis and the precedence of ROS production over the failure of Ca2+ flux homeostasis. J. Cell. Biochem. 114: 1124–1134, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
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Major components of the cardiac conduction system including the sinoatrial node (SAN), atrioventricular node (AVN), the His Bundle, and the right and left bundle branches are too small to be directly visualized by multidetector CT (MDCT) given the limited spatial resolution of current scanners. However, the related anatomic landmarks and variants of this system a well as the areas with special interest to electrophysiologists can be reliably demonstrated by MDCT. Some of these structures and landmarks include the right SAN artery, right atrial cavotricuspid isthmus, Koch triangle, AVN artery, interatrial muscle bundles, and pulmonary veins. In addition, MDCT has an imperative role in demarcating potential arrhythmogenic structures. The aim of this review will be to assess the extent at which MDCT can outline the described anatomic landmarks and therefore provide crucial information used in clinical practice.  相似文献   
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