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Hoffmann DC Textoris C Oehme F Klaassen T Goppelt A Römer A Fugmann B Davidson JM Werner S Krieg T Eming SA 《The Journal of biological chemistry》2011,286(33):28889-28901
α1-Antichymotrypsin (α1-ACT) is a specific inhibitor of leukocyte-derived chymotrypsin-like proteases with largely unknown functions in tissue repair. By examining human and murine skin wounds, we showed that following mechanical injury the physiological repair response is associated with an acute phase response of α1-ACT and the mouse homologue Spi-2, respectively. In both species, attenuated α1-ACT/Spi-2 activity and gene expression at the local wound site was associated with severe wound healing defects. Topical application of recombinant α1-ACT to wounds of diabetic mice rescued the impaired healing phenotype. LC-MS analysis of α1-ACT cleavage fragments identified a novel cleavage site within the reactive center loop and showed that neutrophil elastase was the predominant protease involved in unusual α1-ACT cleavage and inactivation in nonhealing human wounds. These results reveal critical functions for locally acting α1-ACT in the acute phase response following skin injury, provide mechanistic insight into its function during the repair response, and raise novel perspectives for its potential therapeutic value in inflammation-mediated tissue damage. 相似文献
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996.
Plasmodesmatal frequencies in the phloem of leaf minor veins vary considerably, suggesting that photoassimilate is loaded
into the phloem by different strategies. The ecophysiological basis for multiple loading types is unknown. We updated the
analysis of van Bel and Gamalei (Plant Cell Environ 15: 265–270, 1992) with more current phylogenetic data and by treating separately two symplastic loading types, those that load actively by
polymer trapping (synthesis of raffinose family oligosaccharides—RFOs), and those that load passively, by diffusion. The results
indicate a stronger association between passive, symplastic loading and the tree growth form than previously recognized. Apoplastic
loading is highly correlated with the herbaceous habit. There is no correlation between RFO families and growth form. At the
family level, there are no correlations between minor vein types and climate that cannot be explained by the dearth of woody
plants in the arctic for reasons unassociated with phloem loading. However, at the species level, a floristic analysis uncovered
a correlation between the RFO trait and species frequency in tropical and subtropical regions of the world. The correlations
between loading types and both growth form and climate are subtle, probably indirect, and poorly understood. 相似文献
997.
Suso EM Dueland S Rasmussen AM Vetrhus T Aamdal S Kvalheim G Gaudernack G 《Cancer immunology, immunotherapy : CII》2011,60(6):809-818
Immunotherapy targeting the hTERT subunit of telomerase has been shown to induce robust immune responses in cancer patients
after vaccination with single hTERT peptides. Vaccination with dendritic cells (DCs) transfected with hTERT mRNA has the potential
to induce strong immune responses to multiple hTERT epitopes and is therefore an attractive approach to more potent immunotherapy.
Blood samples from such patients provide an opportunity for identification of new, in vivo processed T-cell epitopes that
may be clinically relevant. A 62-year-old female patient underwent radical surgery for a pancreatic adenocarcinoma. After
relapse, she obtained stable disease on gemcitabine treatment. Due to severe neutropenia, the chemotherapy was terminated.
The patient has subsequently been treated with autologous DCs loaded with hTERT mRNA for 3 years. Immunomonitoring was performed
at regular intervals following start of vaccination and clinical outcome measured by CT and PET/CT evaluation. The patient
developed an immune response against several hTERT-derived Th and CTL epitopes. She presently shows no evidence of active
disease based on PET/CT scans. No serious adverse events were experienced and the patient continues to receive regular booster
injections. We here provide evidence for the induction of hTERT-specific immune responses following vaccination of a pancreas
cancer patient with DCs loaded with hTERT mRNA. These responses are associated with complete remission. A thorough analysis
of this patient immune response has provided a unique opportunity to identify novel epitopes, associated with clinical effects.
These will be included in future hTERT vaccines. 相似文献
998.
In plants, small interfering RNAs (siRNAs) can trigger a silencing signal that may spread within a tissue to adjacent cells or even systemically to other organs. Movement of the signal is initially limited to a few cells, but in some cases the signal can be amplified and travel over larger distances. How far silencing initiated by other classes of plant small RNAs (sRNAs) than siRNAs can extend has been less clear. Using a system based on the silencing of the CH42 gene, we have tracked the mobility of silencing signals initiated in phloem companion cells by artificial microRNAs (miRNA) and trans-acting siRNA (tasiRNA) that have the same primary sequence. In this system, both the ta-siRNA and the miRNA act at a distance. Non-autonomous effects of the miRNA can be triggered by several different miRNA precursors deployed as backbones. While the tasiRNA also acts non-autonomously, it has a much greater range than the miRNA or hairpin-derived siRNAs directed against CH42, indicating that biogenesis can determine the non-autonomous effects of sRNAs. In agreement with this hypothesis, the silencing signals initiated by different sRNAs differ in their genetic requirements. 相似文献
999.
W. J. P. Felix L. P. Felix N. F. Melo M. B. M. Oliveira J. H. A. Dutilh R. Carvalho 《Plant Systematics and Evolution》2011,294(3-4):263-271
In this work, the cytotaxonomic implications of the chromosomal characterization of cultivated and native Zephyranthes species described in northeastern Brazil were studied. All individuals had karyotype formed by a set of metacentric chromosomes, in addition to submetacentric and acrocentric chromosomes. In Zephyranthes robusta, 2n?=?12 was observed and karyotype with formula?4M?+?2SM in somatic cells, representing the most symmetric karyotype among the investigated species. Z.?sylvatica showed three different chromosome complement numbers: 2n?=?12 with formula?1M?+?5SM, 2n?=?12?+?1B with 1M?+?5SM?+?(1B), and 2n?=?18 formed by cracks. The cultivated species Z.?rosea Lindl. presented 2n?=?24 with 4M?+?7SM?+?1A, however Z.?grandiflora Lindl. showed the same chromosome number with 2M?+?5SM?+?5A. Zephyranthes aff. rosea Lindl. presented 2n?=?25 with one small metacentric forming a crack in the fourth metacentric pair. Z.?brachyandra has 2n?=?24?+?(1B) and formula?4M?+?3SM?+?5A?+?(1B). Z.?candida Herb. presented 2n?=?38 and karyotype formula?9M?+?10SM. In Habranthus itaobinus numerical variation was observed, with the majority of populations showing a chromosome complement composed of 2n?=?44?+?1B with 5M?+?12SM?+?5A?+?(1B), or 2n?=?44?+?3B in a single population. Mechanisms involved in the formation of these karyotypes from chromosomal imbalance data are discussed. Taken together, data from this study only partially confirm previous counts for epithets and further enhance the cytological variability data previously reported for the genus. 相似文献
1000.
Ohrfelt A Zetterberg H Andersson K Persson R Secic D Brinkmalm G Wallin A Mulugeta E Francis PT Vanmechelen E Aarsland D Ballard C Blennow K Westman-Brinkmalm A 《Neurochemical research》2011,36(11):2029-2042
Parkinson's disease (PD) and Dementia with Lewy bodies (DLB) are neurodegenerative diseases that are characterized by intra-neuronal inclusions of Lewy bodies in distinct brain regions. These inclusions consist mainly of aggregated α-synuclein (α-syn) protein. The present study used immunoprecipitation combined with nanoflow liquid chromatography (LC) coupled to high resolution electrospray ionization Fourier transform ion cyclotron resonance tandem mass spectrometry (ESI-FTICR-MS/MS) to determine known and novel isoforms of α-syn in brain tissue homogenates. N-terminally acetylated full-length α-syn (Ac-α-syn?????) and two N-terminally acetylated C-terminally truncated forms of α-syn (Ac-α-syn????? and Ac-α-syn?????) were found. The different forms of α-syn were further studied by Western blotting in brain tissue homogenates from the temporal cortex Brodmann area 36 (BA36) and the dorsolateral prefrontal cortex BA9 derived from controls, patients with DLB and PD with dementia (PDD). Quantification of α-syn in each brain tissue fraction was performed using a novel enzyme-linked immunosorbent assay (ELISA). 相似文献