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201.
Luca Di Angelo Paolo Di Stefano Andrea Spezzaneve 《Computer methods in biomechanics and biomedical engineering》2013,16(11):1213-1220
The methods for symmetry line detection presented in the literature are typically suited to analyse symmetric upright postures, both standing and seated. The proposed method focuses on the symmetry line detection in subjects assuming asymmetric postures in which this line falls far outside the sagittal plane. The proposed approach evaluates the symmetry line by means of an autoregressive process in order to determine the set of planes suited to slice the back coherently with its geometric spatial configuration. The method is analysed assuming the cutaneous marking as reference and it is compared with a previous one, also developed by these authors. Results are analysed and critically discussed. 相似文献
202.
Andrea Salis Enrico Sanjust Vincenzo Solinas Maura Monduzzi 《Biocatalysis and Biotransformation》2013,31(5):381-386
Three commercial lipases (CLs), A Amano 6 (from Aspergillus niger), M Amano 10 (from Mucor javanicus), and R Amano (from Penicillium roqueforti) – called lipase A, M and R respectively – were characterized in terms of carbohydrate content, protein content and enzymatic activity (p-nitrophenylacetate assay). All the CL preparations contained different proteins as observed from electrophoresis. Lipases were immobilized on Accurel MP1004 porous polypropylene by physical adsorption.The Immobilization process caused a loss of enzymatic activity. The retained activity was similar for lipase M and R (about 15%). In contrast, lipase A retained only the 1.3% of the specific activity of the free lipase. The retained activity of lipases M and R seems to be due to a feature of the support, while the lower activity a of lipase A may be attributed to a strong structure distortion caused by lipase–support interaction. 相似文献
203.
Iride Mascheretti Raffaella Battaglia Davide Mainieri Andrea Altana Massimiliano Lauria Vincenzo Rossi 《The Plant cell》2013,25(2):404-420
The maize (Zea mays) nucleosome remodeling factor complex component101 (nfc101) and nfc102 are putative paralogs encoding WD-repeat proteins with homology to plant and mammalian components of various chromatin modifying complexes. In this study, we generated transgenic lines with simultaneous nfc101 and nfc102 downregulation and analyzed phenotypic alterations, along with effects on RNA levels, the binding of NFC101/NFC102, and Rpd3-type histone deacetylases (HDACs), and histone modifications at selected targets. Direct NFC101/NFC102 binding and negative correlation with mRNA levels were observed for indeterminate1 (id1) and the florigen Zea mays CENTRORADIALIS8 (ZCN8), key activators of the floral transition. In addition, the abolition of NFC101/NFC102 association with repetitive sequences of different transposable elements (TEs) resulted in tissue-specific upregulation of nonpolyadenylated RNAs produced by these regions. All direct nfc101/nfc102 targets showed histone modification patterns linked to active chromatin in nfc101/nfc102 downregulation lines. However, different mechanisms may be involved because NFC101/NFC102 proteins mediate HDAC recruitment at id1 and TE repeats but not at ZCN8. These results, along with the pleiotropic effects observed in nfc101/nfc102 downregulation lines, suggest that NFC101 and NFC102 are components of distinct chromatin modifying complexes, which operate in different pathways and influence diverse aspects of maize development. 相似文献
204.
Weiguo Zhang Malou Fraiture Dagmar Kolb Birgit L?ffelhardt Yoshitake Desaki Freddy F.G. Boutrot Mahmut T?r Cyril Zipfel Andrea A. Gust Frédéric Brunner 《The Plant cell》2013,25(10):4227-4241
Effective plant defense strategies rely in part on the perception of non-self determinants, so-called microbe-associated molecular patterns (MAMPs), by transmembrane pattern recognition receptors leading to MAMP-triggered immunity. Plant resistance against necrotrophic pathogens with a broad host range is complex and yet not well understood. Particularly, it is unclear if resistance to necrotrophs involves pattern recognition receptors. Here, we partially purified a novel proteinaceous elicitor called SCLEROTINIA CULTURE FILTRATE ELICITOR1 (SCFE1) from the necrotrophic fungal pathogen Sclerotinia sclerotiorum that induces typical MAMP-triggered immune responses in Arabidopsis thaliana. Analysis of natural genetic variation revealed five Arabidopsis accessions (Mt-0, Lov-1, Lov-5, Br-0, and Sq-1) that are fully insensitive to the SCFE1-containing fraction. We used a forward genetics approach and mapped the locus determining SCFE1 sensitivity to RECEPTOR-LIKE PROTEIN30 (RLP30). We also show that SCFE1-triggered immune responses engage a signaling pathway dependent on the regulatory receptor-like kinases BRASSINOSTEROID INSENSITIVE1-ASSOCIATED RECEPTOR KINASE1 (BAK1) and SUPPRESSOR OF BIR1-1/EVERSHED (SOBIR1/EVR). Mutants of RLP30, BAK1, and SOBIR1 are more susceptible to S. sclerotiorum and the related fungus Botrytis cinerea. The presence of an elicitor in S. sclerotiorum evoking MAMP-triggered immune responses and sensed by RLP30/SOBIR1/BAK1 demonstrates the relevance of MAMP-triggered immunity in resistance to necrotrophic fungi. 相似文献
205.
Andrea Cossu Ele Ferrannini Poupak Fallahi Alessandro Antonelli Leonardo A. Sechi 《Cytokine》2013,61(2):337-339
Recently Mycobacterium avium subsp. paratuberculosis (Map) was associated to type 1 diabetes mellitus (T1DM). In this study we investigated for Map presence in children affected by T1DM compared to healthy children. A pool of 212 sera from T1DM children at onset was compared to sera from 57 healthy children for humoral immune response towards the Map specific protein MAP3738c by ELISA. Serum concentrations of CXCL10 (pro-Th1) and CCL2 (pro-Th2) chemokines were also measured in both sera pool. Results showed that T1DM children had a stronger seropositivity towards MAP3738c protein compared to healthy children. Data highlighted also the correlation between serum activity of T1DM patients towards the specific protein of Map and the increase of CXCL10 concentration if compared to non-diabetic subjects. In conclusion, an immune response to Map in T1DM patients at onset was observed and this may indicate a role of the bacterium in triggering or precipitating the disease. 相似文献
206.
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209.
Abstract The first unambiguous documentation of hybridism in the genus Doronicum (Senecioneae – Asteraceae) is reported. All our morphological, karyological and molecular data concur to indicate that Doronicum × minutilloi Peruzzi hybr. nov. (2n = 60) is a hybrid growing in Monti Aurunci (Central Italy), originated from the spontaneous crossing D. orientale Hoffm. (2n = 60) × D. columnae Ten. (2n = 60). This new hybrid shows a slightly higher morphological, karyotypic and ribotypic affinity with D. columnae, but shares a trnL-trnF IGS haplotype with D. orientale, and co-occurs with the latter species only; it has reduced fertility and a high potential for vegetative propagation through rhizome fragmentation. Our results led us to suspect in fieri homoploid hybrid speciation. 相似文献
210.
Gergő A. Molnár Vanda Nemes Zsolt Biró Andrea Ludány Zoltán Wagner 《Free radical research》2013,47(12):1359-1366
Post-translational modifications of lens proteins play a crucial role in the formation of cataract during ageing. The aim of our study was to analyze protein composition of the cataractous lenses by electrophoretic and high-performance liquid chromatographic (HPLC) methods.Samples were obtained after extracapsular cataract surgery performed by phacoemulsification technique from cataract patients with type 2 diabetes mellitus (DM CAT, n = 22) and cataract patients without diabetes (non-DM CAT, n = 20), while non-diabetic non-cataractous lenses obtained from cadaver eyes served as controls (CONTR, n = 17). Lens fragments were derived from the surgical medium by centrifugation. Samples were homogenized in a buffered medium containing protease inhibitor. Soluble and insoluble protein fractions were separated by centrifugation. The electrophoretic studies were performed according to Laemmli on equal amounts of proteins and were followed by silver intensification. Oxidized amino acid and Phe content of the samples were also analyzed by HPLC following acid hydrolysis of proteins.Our results showed that soluble proteins represented a significantly lower portion of the total protein content in cataractous lenses in comparison with the control group (CONTR, 71.25%; non-DM CAT, 32.00%; DM CAT, 33.15%; p < 0.05 vs CONTR for both). Among the proteins, the crystallin-like proteins with low-molecular weight can be found both in the soluble and insoluble fractions, and high-molecular weight aggregates were found mainly in the total homogenates. In our HPLC analysis, oxidatively modified derivatives of phenylalanine were detected in cataractous samples. We found higher levels of m-Tyr, o-Tyr and DOPA in the total homogenates of cataractous samples compared to the supernatants. In all three groups, the median Phe/protein ratio of the total homogenates was also higher than that of the supernatants (total homogenates vs supernatants, in the CONTR group 1102 vs 633 μmol/g, in the DM CAT group 1187 vs 382 μmol/g and in the non-DM CAT group 967 vs 252 μmol/g; p < 0.05 for all).In our study we found that oxidized amino acids accumulate in cataractous lenses, regardless of the origin of the cataract. The accumulation of the oxidized amino acids probably results from oxidation of Phe residues of the non-water soluble lens proteins. We found the presence of high-molecular weight protein aggregates in cataractous total homogenates, and a decrease of protein concentration in the water-soluble phase of cataractous lenses. The oxidation of lens proteins and the oxidative modification of Phe residues in key positions may lead to an altered interaction between protein and water molecules and thus contribute to lens opacification. 相似文献