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The role of cell surface glycoproteins in cell behavior can be characterized by their interactions with plant lectins. This
study was designed to identify the effects of lectins on chondrogenesis and osteogenesis in limb bud mesenchymal cells in vitro. Limb bud mesenchymal cells from mouse embryos were cultured in high-density micromass culture. Wheat germ agglutinin (WGA),
concanavalin A (ConA), peanut agglutinin (PNA), Dolichos biflorus agglutinin (DBA) and Ricinus communis agglutinin (RCA) were
added separately to the culture media. Cells were cultured for 5 or 9 days, and cell viability was assayed by neutral red
on day 5. The micromasses were stained with alcian blue, alizarin red S and Von Kossa stains, and alkaline phosphatase assays
were also done. Dolichos biflorus agglutinin induced an increase in chondrogenesis, calcium precipitation and proteoglycan
production. ConA and PNA did not affect chondrocyte differentiation but induced chondrocytes to produce more proteoglycan.
Wheat germ agglutinin reduced chondrification and ossification but induced mesenchymal cells to store lipid droplets. Ricinus
communis agglutinin 1 was toxic and significantly reduced cell survival. In conclusion, DBA was the most effective inducer
of ossification and chondrification. Wheat germ agglutinin induced adipogenesis instead. These assays showed that lectins play important roles in limb bud development. 相似文献
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Negar Seyed Tahereh Taheri Charline Vauchy Magalie Dosset Yann Godet Ali Eslamifar Iraj Sharifi Olivier Adotevi Christophe Borg Pierre Simon Rohrlich Sima Rafati 《PloS one》2014,9(10)
Background
There are several reports demonstrating the role of CD8 T cells against Leishmania species. Therefore peptide vaccine might represent an effective approach to control the infection. We developed a rational polytope-DNA construct encoding immunogenic HLA-A2 restricted peptides and validated the processing and presentation of encoded epitopes in a preclinical mouse model humanized for the MHC-class-I and II.Methods and Findings
HLA-A*0201 restricted epitopes from LPG-3, LmSTI-1, CPB and CPC along with H-2Kd restricted peptides, were lined-up together as a polytope string in a DNA construct. Polytope string was rationally designed by harnessing advantages of ubiquitin, spacers and HLA-DR restricted Th1 epitope. Endotoxin free pcDNA plasmid expressing the polytope was inoculated into humanized HLA-DRB1*0101/HLA-A*0201 transgenic mice intramuscularly 4 days after Cardiotoxin priming followed by 2 boosters at one week interval. Mice were sacrificed 10 days after the last booster, and splenocytes were subjected to ex-vivo and in-vitro evaluation of specific IFN-γ production and in-vitro cytotoxicity against individual peptides by ELISpot and standard chromium-51(51Cr) release assay respectively. 4 H-2Kd and 5 HLA-A*0201 restricted peptides were able to induce specific CD8 T cell responses in BALB/C and HLA-A2/DR1 mice respectively. IFN-γ and cytolytic activity together discriminated LPG-3-P1 as dominant, LmSTI-1-P3 and LmSTI-1-P6 as subdominant with both cytolytic activity and IFN-γ production, LmSTI-1-P4 and LPG-3-P5 as subdominant with only IFN-γ production potential.Conclusions
Here we described a new DNA-polytope construct for Leishmania vaccination encompassing immunogenic HLA-A2 restricted peptides. Immunogenicity evaluation in HLA-transgenic model confirmed CD8 T cell induction with expected affinities and avidities showing almost efficient processing and presentation of the peptides in relevant preclinical model. Further evaluation will determine the efficacy of this polytope construct protecting against infectious challenge of Leishmania. Fortunately HLA transgenic mice are promising preclinical models helping to speed up immunogenicity analysis in a human related mouse model. 相似文献54.
Hormozgan Province plays a vital role in fishery, petroleum, and industrial activities in southern Iran. However, no comprehensive studies on organic pollution have been performed. PCBs and PAHs were analyzed in surface sediments from areas receiving industrial (nine sites), river (one site), and urban (two sites) effluents. The sediment samples were collected in March and September 2010 (in dry and wet seasons) at the highest tidal time. The overall pollution level of PCBs ranged from 2.5 ± 0.8 to 462.0 ± 206.7 ng/g dry weight. CB153 congener dominated in most of the sediment samples. Congener profiles of PCBs showed close similarity with formulations of commercial products such as Aroclor 1260 and 1254 g. A wide range of 55.3 to 1231.6 ng/g dry weight was detected for ∑PAHs. Results of PCA and PCA-MLR tests confirmed both petrogenic and pyrogenic origins for PAH pollution. The higher means of ∑PAHs and ∑PCBs in industrial and urban wastewaters were found near the shore, evidencing the role of these wastewaters in the PAH and PCB contamination in Hormozgan sediment. The concentrations of PAHs and PCBs in detected hotspots exceed the U.S. NOAA sediment quality guidelines. 相似文献
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Arockiaraj J Vanaraja P Easwvaran S Singh A Alinejaid T Othman RY Bhassu S 《Fish & shellfish immunology》2011,31(1):81-89
Arginine kinase-1 (MrAK-1) was sequenced from the freshwater prawn Macrobrachium rosenbergii using Illumina Solexa Genome Analyzer Technique. MrAK-1 consisted of 1068 bp nucleotide encoded 355 polypeptide with an estimated molecular mass of 40 kDa. MrAK-1 sequence contains a potential ATP:guanido phosphotransferases active domain site. The deduced amino acid sequence of MrAK-1 was compared with other 7 homologous arginine kinase (AK) and showed the highest identity (96%) with AK-1 from cherry shrimp Neocaridina denticulate. The qRT-PCR analysis revealed a broad expression of MrAK-1 with the highest expression in the muscle and the lowest in the eyestalk. The expression of MrAK-1 after challenge with the infectious hypodermal and hematopoietic necrosis virus (IHHNV) was tested in muscle. In addition, MrAK-1 was expressed in Escherichia coli by prokaryotic expression plasmid pMAL-c2x. The optimum temperature (30 °C) and pH (8.5) was determined for the enzyme activity assay. MrAK-1 showed significant (P < 0.05) activity towards 10-50 mM ATP concentration. The enzyme activity was inhibited by α-ketoglutarate, glucose and ATP at the concentration of 10, 50 and 100 mM respectively. Conclusively, the findings of this study indicated that MrAK-1 might play an important role in the coupling of energy production and utilization and the immune response in shrimps. 相似文献
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Tahereh Karami-jamour Alinaghi Mirmoayedi Abbasali Zamani Yadolah Khajehzadeh 《Journal of Insect Behavior》2018,31(2):222-239
In this study the changes in Aphis gossypii Glover populations tended by the homopteran- tending ant, Tapinoma simrothi Krausse when exposed to the natural enemies Chrysoperla carnea Stephens and Coccinellia septempunctata Mulsant was studied. We also studied the effect of ant’s attendance on the consequence of intraguild predation (IGP) between these two predators. The presence of ants T. simrothi had deterrent impact on natural enemies of A. gossypii compared to control aphid populations in absence of ants. Equally we observed that IGP between two aphid predators decreased when T. simrothi was present. The lowest IGP level was observed when both aphids and ants were present in the microcosm arena. In the microcosm arena the presence of ants had an indirect effect on the occurrence of IGP. Our results suggest that although the mutualistic ants have an indirect impact on the IGP by aphidophages predators, but their roles should not be ignored. 相似文献
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Touraj Rahimi Ali Niazi Tahereh Deihimi Seyed Mohsen Taghavi Shahab Ayatollahi Esmaeil Ebrahimie 《Functional & integrative genomics》2018,18(5):533-543
One of the main challenges in elimination of oil contamination from polluted environments is improvement of biodegradation by highly efficient microorganisms. Bacillus subtilis MJ01 has been evaluated as a new resource for producing biosurfactant compounds. This bacterium, which produces surfactin, is able to enhance bio-accessibility to oil hydrocarbons in contaminated soils. The genome of B. subtilis MJ01 was sequenced and assembled by PacBio RS sequencing technology. One big contig with a length of 4,108,293 bp without any gap was assembled. Genome annotation and prediction of gene showed that MJ01 genome is very similar to B. subtilis spizizenii TU-B-10 (95% similarity). The comparison and analysis of orthologous genes carried out between B. subtilis MJ01, reference strain B. subtilis subsp. subtilis str. 168, and close relative spizizenii TU-B-10 by microscope platform and various bioinformatics tools. More than 88% of 4269 predicted coding sequences in MJ01 had at least one similar sequence in genome of reference strain and spizizenii TU-B-10. Despite this high similarity, some differences were detected among encoding sequences of non-ribosome protein and bacteriocins in MJ01 and spizizenii TU-B-10. MJ01 has unique nucleotide sequences and a novel predicted lasso-peptide bacteriocin; it also has not any similar nucleotide sequence in non-redundant nucleotide data base. 相似文献
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Sheler Ahmadi Farideh Kazemi Seyedeh Zahra Masoumi Parisa Parsa Ghodratollah Roshanaei 《International breastfeeding journal》2016,11(1):30