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51.
The present study was designed to investigate the capability of bovine neutrophil granulocytes to produce the minor acute phase protein alpha(1)-acid glycoprotein (AGP, Orososmucoid). Bovine neutrophils contain a high MW (50-60kDa) AGP isoform (PMN-AGP), as determined by Western blotting and confirmed by fluorescence microscopy. The presence of AGP in bovine neutrophils has been confirmed by fluorescence immunocytometry. In addition, bovine neutrophils contain also a 42-45kDa isoform, which has the same MW as plasma-, liver-delivered, AGP. cDNA sequence of plasma- and PMN-AGP revealed that (i) the two proteins are products of the same gene; (ii) the differences in molecular weight are due do different post-translational modifications. This result was confirmed by deglycosylation of the two glycoforms. Exocytosis studies showed that isolated neutrophils exposed to several challengers, including Zymosan activated serum (ZAS) and phorbol 12-myristate 13-acetate (PMA), which mimic the inflammatory activation, released PMN-AGP as early as 15min. AGP's mRNA is physiologically expressed by mature resting neutrophils. Real-time PCR on LPS, ZAS and PMA challenged cells revealed that the level of expression apparently does not increase after inflammatory activation. Collectively, the findings reported in this paper proved that PMN-AGP: (i) is a hyperglycosylated glycoform of plasma AGP, (ii) is stored in granules, and (iii) is released by neutrophils in response to activation. Due to its anti-inflammatory activity, PMN-AGP may work as a fine tuning of the neutrophils functions in the inflammatory focus, i.e. it can reduce the damages caused by an excess of inflammatory response.  相似文献   
52.
The acute phase protein alpha(1)-acid glycoprotein (AGP--Orosomucoid) is a lipocalin with immunomodulatory functions. The present study provides evidence that the plasma glycoforms of AGP inhibit the migration of bovine monocytes in response to classical chemoattractants. The inhibition is specific, since neutrophils are apparently not affected. To investigate the molecular basis of this finding, the expression of the molecules mostly involved in chemotaxis, including CD18, CD11b and CD47 was studied. It was found that the incubation of activated monocytes with acute phase concentration of AGP (0.9 mg/mL) induces a down-regulation of CD18, and has no apparent influence on CD11b and CD47. RT-PCR expression studies on CD18, CD11b and CD47 mRNA revealed that AGP treatment does not modify the expression rate of these genes. Since AGP treatment is related to a down-regulation of CD18 on the surface of the monocytes, the authors suggest that one of its possible functions consists in specifically reducing the firm adhesion phase of bovine monocytes to the endothelium.  相似文献   
53.
Globe artichoke (Cynara cardunculus L. var. scolymus) plants of a typical landrace (‘Montelupone A’) from the Marche region (Italy) and three commercial cultivars (‘Apollo’, ‘Romanesco C3’, ‘Exploter’) were compared as a detailed analysis of their productive, morphological, qualitative, and nutritional parameters was carried out to characterise their particularities and suitability for the fresh market or the processing industry. Cultivar ‘Apollo’ stands out for its qualitative and agronomic aspects, with ‘Romanesco C3’ showing high flower head yield, as the most important Romanesco cultivar that is widely cultivated in central Italy. ‘Exploter’ shows high productivity and qualitative characteristics. The lower phenol content of ‘Exploter’ indicates its suitability for processing as a fresh cut preparation. The ‘Montelupone A’ landrace is characterised by beneficial nutritional values that indicate its use for fresh consumption and as a source of antioxidant compounds. The ‘Apollo’ and ‘Romanesco C3’ commercial cultivars show higher processing yield due to flower head characteristics. In particular, ‘Apollo’ has an interesting profile according to its technological qualitative and nutritional value. ‘Exploter’ differs in its high yield and suitability for the fresh market. Analysis of the ‘Montelupone A’ landrace confirms its interesting qualitative and nutritional values.  相似文献   
54.

Context

Ecological networks are often designed based on the degree of suitability and permeability of land cover classes, as obtained by estimating the statistical relationships between occurrence data and classes coverage using habitat suitability models (HSMs). Considering only the classes coverage, but not their spatial arrangement, frequently prevents HSMs from correctly identifying nodes and connectivity elements.

Objectives

We propose a new approach in the design of ecological networks starting from the relationship between occurrence data and both land cover classes coverage and spatial arrangement, as calculated for different simulated species perceptions of the landscape (SSPLs, corresponding to different combinations of classes alternatively assuming the role of nodes, connectivity elements, or matrix).

Methods

The approach consists of comparing the ability to explain the observed species occurrence of both the nodes coverage and the connectivity degree provided by both nodes and connectivity elements, calculated for each SSPL. The better performing SSPL will provide information about the land cover classes that should be considered in designing an ecological network for the species, as well as their role in the network.

Results

When applied to the Hazel Dormouse in an agricultural landscape in northern Italy, the method proved effective and allowed us to identify woodlands and hedgerows as nodes, and poplar cultivations, biomasses and reforestations as connectivity elements.

Conclusions

The proposed method can be adopted to identify nodes and connectivity elements for virtually every species sensitive to fragmentation, and has important practical implications when integrated in landscape management plans developed to guarantee ecological connectivity.
  相似文献   
55.
Adding biochar to soils and maintaining high earthworm biomasses are potential ways to increase the fertility of tropical soils and the sustainability of crop production in the spirit of agroecology and ecological engineering. However, a thorough functional assessment of biochar effect on plant growth and resource allocations is so far missing. Moreover, earthworms and biochar increase mineral nutrient availability through an increase in mineralization and nutrient retention respectively and are likely to interact through various other mechanisms. They could thus increase plant growth synergistically. This hypothesis was tested for rice in a greenhouse experiment. Besides, the relative effects of biochar and earthworms were compared in three different soil treatments (a nutrient rich soil, a nutrient poor soil, a nutrient poor soil supplemented with fertilization). Biochar and earthworm effects on rice growth and resource allocation highly depended on soil type and were generally additive (no synergy). In the rich soil, there were both clear positive biochar and earthworm effects, while there were generally only positive earthworm effects in the poor soil, and neither earthworm nor biochar effect in the poor soil with fertilization. The analysis of earthworm and biochar effects on different plant traits and soil mineral nitrogen content, confirmed that they act through an increase in nutrient availability. However it also suggested that another mechanism, such as the release in the soil of molecules recognized as phytohormones by plants, is also involved in earthworm action. This mechanism could for example help explaining how earthworms increase rice resource allocation to roots and influence the allocation to grains.  相似文献   
56.
In this paper molecular analysis, physical, technological, and chemical traits were used to estimate the level of variation on five accessions of a locally adapted Sicilian faba bean (Vicia faba L.) landrace named ‘Larga di Leonforte’. DNA analysis was performed using the Amplified Fragment Length Polymorphism (AFLP) molecular marker class and two other faba beans (cv. ‘Aguadulce Samba’—Spain—and landrace ‘Locale di Modica’—Sicily) were used as controls. Although the accessions of ‘Larga di Leonforte’ varied significantly for most of the agronomical and physical traits, this landrace generally had a heavy seed weight, short but large pods, and no more than two seeds per pod. This last characteristic allowed for erect pod angle attitude at maturity. Idratation data showed difference among accessions in seed weight at full hydration and in absorption rate at the very beginning of the hydration process, while any difference among accessions emerged in terms of cooking properties. The six AFLP Eco+3/Mse+3 different primer combinations applied in this research revealed different levels of polymorphism among the faba bean accessions and a total number of 346 amplicons were generated. Around 60% of amplicons displayed a polymorphic pattern among different accessions. Cluster analysis on morphological, technological, chemical and molecular data placed the all five ‘Larga di Leonforte’ accessions into a separated group, and the Sicilian material shares a fairly large amount of similarity with respect to the cultivar ‘Aguadulce Samba’ selected in Spain.  相似文献   
57.
The tumor suppressor programmed cell death protein 4 (PDCD4) inhibits the translation initiation factor eIF4A, an RNA helicase that catalyzes the unwinding of secondary structure at the 5' untranslated region (5'UTR) of messenger RNAs (mRNAs). In response to mitogens, PDCD4 was rapidly phosphorylated on Ser67 by the protein kinase S6K1 and subsequently degraded via the ubiquitin ligase SCF(betaTRCP). Expression in cultured cells of a stable PDCD4 mutant that is unable to bind betaTRCP inhibited translation of an mRNA with a structured 5'UTR, resulted in smaller cell size, and slowed down cell cycle progression. We propose that regulated degradation of PDCD4 in response to mitogens allows efficient protein synthesis and consequently cell growth.  相似文献   
58.
The in vitro permissivity to infection with homologous and heterologous bovine viral diarrhoea virus (BVDV) strains of bovine peripheral blood mononuclear cells (PBMCs) from eight na?ve and eight BVDV-1b immune animals was studied. Four reference strains (BVDV-1a NADL, BVDV-1b NY-1, BVDV-2 125 and BVDV-2 890) were selected, based on genotype, prevalence and biotype. Virus neutralizing antibody titres were determined at bleeding and the viral loads were measured in PBMCs by end point titration in cell culture and by real-time PCR. PBMCs from both na?ve and immune animals became infected by all BVDV strains tested, although virus titres were lower for immune heifers than na?ve ones; the differences were significant for NADL (P<0.05) and 890 (P<0.001) strains. The in vitro model used in this study showed that PBMCs from immune animals are susceptible to re-infection with both homologous and heterologous BVDV strains, albeit at a lower extent than na?ve cattle.  相似文献   
59.
60.
The only supernovae (SNe) to show gamma-ray bursts (GRBs) or early x-ray emission thus far are overenergetic, broad-lined type Ic SNe (hypernovae, HNe). Recently, SN 2008D has shown several unusual features: (i) weak x-ray flash (XRF), (ii) an early, narrow optical peak, (iii) disappearance of the broad lines typical of SN Ic HNe, and (iv) development of helium lines as in SNe Ib. Detailed analysis shows that SN 2008D was not a normal supernova: Its explosion energy (E approximately 6x10(51) erg) and ejected mass [ approximately 7 times the mass of the Sun (M(middle dot in circle))] are intermediate between normal SNe Ibc and HNe. We conclude that SN 2008D was originally a approximately 30 M(middle dot in circle) star. When it collapsed, a black hole formed and a weak, mildly relativistic jet was produced, which caused the XRF. SN 2008D is probably among the weakest explosions that produce relativistic jets. Inner engine activity appears to be present whenever massive stars collapse to black holes.  相似文献   
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