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41.
42.
TLR4-mediated survival of macrophages is MyD88 dependent and requires TNF-alpha autocrine signalling
Lombardo E Alvarez-Barrientos A Maroto B Boscá L Knaus UG 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(6):3731-3739
Modulation of macrophage survival is a critical factor in the resolution of inflammatory responses. Exposure to LPS protects innate immune cells against apoptosis, although the precise pathways responsible for prolongation of macrophage survival remain to be fully established. The goal of this study was to characterize the mechanism of TLR4-mediated survival of murine bone marrow-derived macrophages upon M-CSF withdrawal in more detail. Using a combination of knockout mice and pharmacological inhibitors allowed us to show that TLR4 and TLR2 stimulation promotes long-term survival of macrophages in a MyD88-, PI3K-, ERK-, and NF-kappaB-dependent manner. LPS-induced long-term, but not short-term, survival requires autocrine signaling via TNF-alpha and is facilitated by a general cytoprotective program, similar to that mediated by M-CSF. TLR4-mediated macrophage survival is accompanied by a remarkable up-regulation of specific cell surface markers, suggesting that LPS stimulation leads to the differentiation of macrophages toward a mixed macrophage/dendritic cell-like phenotype. 相似文献
43.
Keith Lombardo Jeffrey S. Fehmi Kevin J. Rice Emilio A. Laca 《Restoration Ecology》2007,15(2):177-178
We found no significant effect (p > 0.38) of clipping surrounding non‐native annuals on the performance or survival of plantings of the native Nassella pulchra. However, the preplanting productivity of the three sites had a significant effect (p < 0.001) on the demography and water relations of Nassella. Survival was 85% on the lowest productivity site and it decreased by 6% for each additional 100 kg in average aboveground productivity between 2,400 and 3,600 kg/ha. Plants experienced greater water stress in higher productivity sites. Together, these results suggest that the original habitat of N. pulchra may have been in more marginal ecological sites rather than the more fertile soils of the Central Valley. 相似文献
44.
José MC Ribeiro Bruno Arcà Fabrizio Lombardo Eric Calvo My Van Phan Prafulla K Chandra Stephen K Wikel 《BMC genomics》2007,8(1):1-27
Background
The number of completely sequenced plastid genomes available is growing rapidly. This array of sequences presents new opportunities to perform comParative analyses. In comParative studies, it is often useful to compare across wide phylogenetic spans and, within angiosperms, to include representatives from basally diverging lineages such as the genomes reported here: Nuphar advena (from a basal-most lineage) and Ranunculus macranthus (a basal eudicot). We report these two new plastid genome sequences and make comparisons (within angiosperms, seed plants, or all photosynthetic lineages) to evaluate features such as the status of ycf15 and ycf68 as protein coding genes, the distribution of simple sequence repeats (SSRs) and longer dispersed repeats (SDR), and patterns of nucleotide composition.Results
The Nuphar [GenBank:NC_008788] and Ranunculus [GenBank:NC_008796] plastid genomes share characteristics of gene content and organization with many other chloroplast genomes. Like other plastid genomes, these genomes are A+T-rich, except for rRNA and tRNA genes. Detailed comparisons of Nuphar with Nymphaea, another Nymphaeaceae, show that more than two-thirds of these genomes exhibit at least 95% sequence identity and that most SSRs are shared. In broader comparisons, SSRs vary among genomes in s of abundance and length and most contain repeat motifs based on A and T nucleotides.Conclusion
SSR and SDR abundance varies by genome and, for SSRs, is proportional to genome size. Long SDRs are rare in the genomes assessed. SSRs occur less frequently than predicted and, although the majority of the repeat motifs do include A and T nucleotides, the A+T bias in SSRs is less than that predicted from the underlying genomic nucleotide composition. In codon usage third positions show an A+T bias, however variation in codon usage does not correlate with differences in A+T-richness. Thus, although plastome nucleotide composition shows "A+T richness", an A+T bias is not apparent upon more in-depth analysis, at least in these aspects. The pattern of evolution in the sequences identified as ycf15 and ycf68 is not consistent with them being protein-coding genes. In fact, these regions show no evidence of sequence conservation beyond what is normal for non-coding regions of the IR. 相似文献45.
Angiotensin receptor I stimulates osteoprogenitor proliferation through TGFβ‐mediated signaling
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46.
47.
Lai MC Lombardo MV Pasco G Ruigrok AN Wheelwright SJ Sadek SA Chakrabarti B;MRC AIMS Consortium Baron-Cohen S 《PloS one》2011,6(6):e20835
Autism spectrum conditions (ASC) affect more males than females in the general population. However, within ASC it is unclear if there are phenotypic sex differences. Testing for similarities and differences between the sexes is important not only for clinical assessment but also has implications for theories of typical sex differences and of autism. Using cognitive and behavioral measures, we investigated similarities and differences between the sexes in age- and IQ-matched adults with ASC (high-functioning autism or Asperger syndrome). Of the 83 (45 males and 38 females) participants, 62 (33 males and 29 females) met Autism Diagnostic Interview-Revised (ADI-R) cut-off criteria for autism in childhood and were included in all subsequent analyses. The severity of childhood core autism symptoms did not differ between the sexes. Males and females also did not differ in self-reported empathy, systemizing, anxiety, depression, and obsessive-compulsive traits/symptoms or mentalizing performance. However, adult females with ASC showed more lifetime sensory symptoms (p = 0.036), fewer current socio-communication difficulties (p = 0.001), and more self-reported autistic traits (p = 0.012) than males. In addition, females with ASC who also had developmental language delay had lower current performance IQ than those without developmental language delay (p<0.001), a pattern not seen in males. The absence of typical sex differences in empathizing-systemizing profiles within the autism spectrum confirms a prediction from the extreme male brain theory. Behavioral sex differences within ASC may also reflect different developmental mechanisms between males and females with ASC. We discuss the importance of the superficially better socio-communication ability in adult females with ASC in terms of why females with ASC may more often go under-recognized, and receive their diagnosis later, than males. 相似文献
48.
Giusti L Cetani F Ciregia F Da Valle Y Donadio E Giannaccini G Banti C Pardi E Saponaro F Basolo F Berti P Miccoli P Pinchera A Marcocci C Lucacchini A 《Molecular bioSystems》2011,7(3):687-699
Parathyroid tumours are heterogeneous and in some cases the diagnosis may be difficult using histological features. In this study we used a two-dimensional electrophoresis (2D)/mass spectrometry (MS)-based approach to examine the global changes of parathyroid adenoma tissues protein profile compared to the parathyroid normal tissues. Validation of protein expression was performed by immunoblotting using specific antibodies. Ingenuity software was used to identify the biological processes to which these proteins belong and to construct a potential network. A total of 30 proteins were found to be differentially expressed, of which 22 resulted in being over-expressed. Proteins identified by 2D/MS/MS proteomics were classified into functional categories and a major change (≥ 2-fold) in terms of expression was found in proteins involved in response to biotic stimuli, cell organization and signal transduction. After Ingenuity analysis, 14-3-3 ζ/δ appears to be a key protein in the network of parathyroid adenoma, where it is linked to other proteins such as annexin A2, B box and SPRY domain-containing protein (BSPRY), p53 and epidermal growth factor receptor (EGFR). Our results suggest that the proteomic approach was able to differentiate the protein profiles of normal parathyroid and parathyroid adenoma and identify a panel of proteins which are differentially expressed. The functional role of these proteins in the network of intracellular pathways is discussed. 相似文献
49.
Bianchi FT Camera P Ala U Imperiale D Migheli A Boda E Tempia F Berto G Bosio Y Oddo S LaFerla FM Taraglio S Dotti CG Di Cunto F 《PloS one》2011,6(7):e22370
Alzheimer disease (AD) is a neurodegenerative disorder characterized by progressive decline of cognitive function that represents one of the most dramatic medical challenges for the aging population. Aβ peptides, generated by processing of the Amyloid Precursor Protein (APP), are thought to play a central role in the pathogenesis of AD. However, the network of physical and functional interactions that may affect their production and deposition is still poorly understood. The use of a bioinformatic approach based on human/mouse conserved coexpression allowed us to identify a group of genes that display an expression profile strongly correlated with APP. Among the most prominent candidates, we investigated whether the collagen chaperone HSP47 could be functionally correlated with APP. We found that HSP47 accumulates in amyloid deposits of two different mouse models and of some AD patients, is capable to physically interact with APP and can be relocalized by APP overexpression. Notably, we found that it is possible to reduce the levels of secreted Aβ peptides by reducing the expression of HSP47 or by interfering with its activity via chemical inhibitors. Our data unveil HSP47 as a new functional interactor of APP and imply it as a potential target for preventing the formation and/or growth amyloid plaques. 相似文献
50.
Goi G Massaccesi L Burlina AP Baquero Herrera CJ Lombardo A Tettamanti G Burlina AB 《Biochimica et biophysica acta》2005,1741(3):300-306
OBJECTIVE: Fabry disease results from a deficiency in the activity of alpha-d-galactosidase A and subsequent accumulation of neutral glycosphingolipids in lysosomes. This study investigated whether lysosomal enzymes can indicate biochemical changes in the lysosomal apparatus induced by enzyme replacement therapy (ERT). DESIGN AND METHODS: Eight patients were monitored by clinical and biochemical tests and several lysosomal glycohydrolases were measured in plasma and leucocytes. RESULTS: Before starting ERT, beta-d-glucuronidase in leukocytes was markedly increased. After 1 month of therapy, enzyme levels dropped in all patients. In the patients who regularly followed the therapy, the enzyme levels remained stable for the next 20 months. In one patient who interrupted therapy for 2 months, the enzyme levels rose again. CONCLUSIONS: Lysosomal enzymes can be useful for monitoring biochemical changes in patients with Fabry disease receiving ERT. Though these findings refer to only a small number of patients, the correlation between beta-d-glucuronidase levels and ERT is interesting and might serve as a basis for further studies to define the potential of this enzyme in monitoring the effects of ERT in lysosomal storage disorders. 相似文献