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801.
Elaine Stopforth Albert W. H. Neitz Anabella R. M. Gaspar 《Experimental & applied acarology》2010,51(4):309-325
A proteomics approach was employed to identify proteins secreted into the hemolymph of Ornithodorus savignyi ticks 2 h after immune-challenge with the yeast, Candida albicans. Profiling of the proteins present in hemolymph of unchallenged ticks versus ticks challenged with heat-killed yeast revealed
five proteins to be differentially expressed. The modulated protein spots were subjected to tandem mass spectrometry (MS/MS)
analysis, but could not be positively identified. These proteins can be assigned to the immune response as they were not induced
after aseptic injury. In an attempt to identify hemolymph proteins that recognize and bind to yeast cells, hemolymph obtained
from both unchallenged and challenged ticks was incubated with C. albicans. Elution of the bound proteins followed by SDS–PAGE analysis indicated that three proteins (97, 88 and 26 kDa) present in
both unchallenged and challenged hemolymph samples bind to yeast cells. The constant presence of these three proteins in tick
hemolymph leads us to believe that they may be involved in non-self recognition and participate in yeast clearance from tick
plasma. The analyzed yeast-binding proteins could also not be positively identified, suggesting that all the tick immune proteins
investigated in this study are novel. 相似文献
802.
Michelle J. Paddack John D. Reynolds Consuelo Aguilar Richard S. Appeldoorn Jim Beets Edward W. Burkett Paul M. Chittaro Kristen Clarke Rene Esteves Ana C. Fonseca Graham E. Forrester Alan M. Friedlander Jorge García-Sais Gaspar González-Sansón Lance K.B. Jordan David B. McClellan Margaret W. Miller Philip P. Molloy Peter J. Mumby Ivan Nagelkerken Isabelle M. Côté 《Current biology : CB》2009,19(7):590-595
803.
804.
Geographic distribution of HBsAg subtypes in Brazil 总被引:1,自引:0,他引:1
HBsAg positive serum samples (896) from five brazilian regions were analysed for HBsAg subtypes. The presence of five different subtypes (ayw2, ayw3, ayw4, adw2 and adw4) was detected. In Northern region subtypes adw4 (41.2%) and adw2 (37.2%) were predominant. In the North East only subtype adw2 was encountered. In Central West, South-East and South, subtypes ayw2, ayw3, adw2 and adw4 were present, with predominance of adw2 in Central West and South East (84.3% and 69.4% respectively) whereas in the South the predominant subtype was ayw3 (41.9%) followed by ayw2 (36.4%). Subtypes ayw1, ayr and adr were not found among the samples studied. These results show the difference in the incidence of HBsAg subtypes in the different regions of Brazil and their significance in relation to the colonization and migrations in this country. 相似文献
805.
Does altered nitrogen metabolism and H2O2 accumulation explain the vitrified status of the fully habituated callus of Beta vulgaris (L.)? 总被引:2,自引:0,他引:2
Frédérik Le Dily Claude Huault Thomas Gaspar Jean-Pierre Billard 《Plant Cell, Tissue and Organ Culture》1993,35(1):69-74
The habituated callus is a vitrified tissue which has two main biochemical characteristics both leading to production of toxic forms of oxygen: first the blockage of the porphyrin pathway and a lack of H2O2 detoxifying enzymes (catalase and peroxidases); secondly a deviation of the nitrogen metabolism induced by NH3 accumulation. Ammonia detoxification is ensured by increased glutamate dehydrogenase activity and accumulation of both proline and polyamines. A putative linkage between proline synthesis and the HMP pathway, as proposed for animal proliferating tissues (Phang 1985), might explain a high purine biosynthesis and cytokinin autonomy.Abbreviations FFA
free fatty acids
- 6PG-DH
6-phosphogluconate dehydrogenase
- G6P-DH
glucose-6-phosphate dehydrogenase
- GLU
glutamate
- GDH
glutamate dehydrogenase
- GR
glutathion reductase
- H
habituated callus
- HMP
hexoses-monophosphate
- IAA
indolyl-acetic acid
- LOX
lipoxygenase
- MDA
malondialdehyde
- N
normal callus
- OAT
ornithine aminotransferase
- ORN
ornithine
- PAs
polyamines
- P5C
pyrroline-5-carboxylate
- P5CR
pyrroline-5-carboxylate reductase
- PP-ribose-P
phosphoribosyl pyrophosphate
- SOD
superoxide dismutase 相似文献
806.
Melinda Andrasi Rose Bustos Attila Gaspar Frank A. Gomez Almos Klekner 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(21):1801-1808
The applicability of micellar electrokinetic capillary chromatography (MEKC) for the analysis of temozolomide (TMZ) and its degradants, 3-methyl-(triazen-1-yl)imidazole-4-carboxamide (MTIC) and 5-amino-imidazole-4-carboxamide (AIC) has been studied. Using short-end injection, the analysis of TMZ and its degradants could be performed within 1.2 min. The obtained precision of migration times was better than 1.6 RSD%, and the limit of quantitation (LOQ) was 0.31–0.93 μg/mL. The therapeutic concentration of TMZ in blood samples can be determined after direct sample injection and conventional on-capillary UV detection. The proposed MEKC method was applied to study the stability of TMZ in water and serum at different pH values. It was established that the half-life of the TMZ in vitro serum at room temperature was 33 min, close to the half-life (28 min) obtained in water at pH 7.9. 相似文献
807.
A GC-ECD titration of IAA in normal auxin (2,4-D)-requiring and auxin-independent (habituated) sugarbeet callus revealed an equal amount in both tissues. A comparison of the content and pattern (through starch gel electrophoresis) of soluble, membrane and wall peroxidases indicated that normal tissues contained a higher level of isoperoxidases. Normal tissues also were found to contain higher levels of peroxidase inhibitors and auxin protectors. The hypothesized peroxidase-mediated higher rate of auxin destruction in normal sugarbeet callus is supposed to be counterbalanced by the 2,4-D-controlled auxin protectors. 相似文献