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11.
B. Duduk A. Calari S. Paltrinieri N. Duduk & A. Bertaccini 《The Annals of applied biology》2009,154(2):219-229
During a survey of large carrot fields in Serbia, plants showing leaf reddening and/or yellowing, adventitious shoot production and reduction in taproot size and quality were observed in a low percentage of plants. To verify phytoplasma association with the described symptoms and to carry out pathogen differentiation, PCR assays followed by restriction fragment length polymorphism (RFLP) analyses and/or sequencing of phytoplasma 16Sr DNA and ribosomal protein genes l22 and s3 , tuf , putative aa kinase plus ribosomal recycling factor genes and DNA helicase gene were carried out. Phytoplasmas belonging to 16SrI-A and 16SrI-B ribosomal subgroups and to rpI-A and rpI-B ribosomal protein subgroups, respectively, were identified by RFLP analyses in 13 of 15 symptomatic plants tested. No amplification was obtained with non-symptomatic carrot samples. The identification was confirmed by sequence analyses of the phytoplasma genes studied. In two carrot samples, presence of interoperon sequence heterogeneity was detected and phytoplasma strains were identified as belonging to 16SrI group but were not assigned to any 16S rRNA or ribosomal protein subgroup. This research allowed the first molecular identification of phytoplasmas infecting carrot in Serbia using several molecular markers, and it indicates that under field conditions in non-epidemic outbreaks a certain amount of genetic mutation may occur in conserved genes of these prokaryotes. 相似文献
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Assunta Lombardi Rosalba Senese Rita De Matteis Rosa Anna Busiello Federica Cioffi Fernando Goglia Antonia Lanni 《PloS one》2015,10(2)
3,5-diiodo-l-thyronine (T2), a thyroid hormone derivative, is capable of increasing energy expenditure, as well as preventing high fat diet-induced overweight and related metabolic dysfunction. Most studies to date on T2 have been carried out on liver and skeletal muscle. Considering the role of brown adipose tissue (BAT) in energy and metabolic homeostasis, we explored whether T2 could activate BAT thermogenesis. Using euthyroid, hypothyroid, and T2-treated hypothyroid rats (all maintained at thermoneutrality) in morphological and functional studies, we found that hypothyroidism suppresses the maximal oxidative capacity of BAT and thermogenesis, as revealed by reduced mitochondrial content and respiration, enlarged cells and lipid droplets, and increased number of unilocular cells within the tissue. In vivo administration of T2 to hypothyroid rats activated BAT thermogenesis and increased the sympathetic innervation and vascularization of tissue. Likewise, T2 increased BAT oxidative capacity in vitro when added to BAT homogenates from hypothyroid rats. In vivo administration of T2 to hypothyroid rats enhanced mitochondrial respiration. Moreover, UCP1 seems to be a molecular determinant underlying the effect of T2 on mitochondrial thermogenesis. In fact, inhibition of mitochondrial respiration by GDP and its reactivation by fatty acids were greater in mitochondria from T2-treated hypothyroid rats than untreated hypothyroid rats. In vivo administration of T2 led to an increase in PGC-1α protein levels in nuclei (transient) and mitochondria (longer lasting), suggesting a coordinate effect of T2 in these organelles that ultimately promotes net activation of mitochondrial biogenesis and BAT thermogenesis. The effect of T2 on PGC-1α is similar to that elicited by triiodothyronine. As a whole, the data reported here indicate T2 is a thyroid hormone derivative able to activate BAT thermogenesis. 相似文献
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David W. Pennington Kirana Chomkhamsri Rana Pant Marc-Andree Wolf Giovanni Bidoglio Klaus Kögler Pavel Misiga Michel Sponar Bettina Lorz Guido Sonnemann Paolo Masoni Hongtao Wang Lin Ling Carla Castanho Chen Sau Soon Maurizio Fieschi Assunta Filareto Michael Hauschild 《The International Journal of Life Cycle Assessment》2010,15(3):231-237
Introduction
The European Commission is supporting the development of the International Reference Life Cycle Data System (ILCD). This consists primarily of the ILCD Handbook and the ILCD Data Network. This paper gives an insight into the scientific positions of business, governments, consultants, academics, and others that were expressed at this public consultation workshop.Workshop focus
The workshop focused on four of the topics of the main guidance documents of the ILCD Handbook: (1) general guidance on life cycle assessment (LCA); (2) guidance for generic and average life cycle inventory (LCI) data sets; (3) requirements for environmental impact assessment methods, models and indicators for LCA; and (4) review schemes for LCA.Workshop participation
This consultation workshop was attended by more than 120 participants during the 4 days of the workshop. Representatives came from 23 countries, from both within and outside the European Union.Workshop structure
Approximately half of the participants were from business associations or individual companies. Another 20% were governmental representatives. Others came predominantly from consultancies and academia.Results
This public consultation workshop provided valuable inputs into the overall ILCD Handbook developments as well as for further development. This paper focuses on some of the main scientific issues that were raised. 相似文献15.
Paola Palozza Rossella Simone Assunta Catalano Alma Boninsegna Volker Böhm Kati Fröhlich Maria Cristina Mele Giovanni Monego Franco O. Ranelletti 《The Journal of nutritional biochemistry》2010,21(1):34-46
The present study was undertaken to examine whether lycopene is able to counteract 7-ketocholesterol (7-KC)-induced oxidative stress and apoptosis in human macrophages. Human THP-1 macrophages were exposed to 7-KC (10–25 μM) alone and in combination with lycopene (0.5–2 μM), and we monitored changes in cell oxidative status [reactive oxygen species (ROS) production, NOX-4, hsp70 and hsp90 expressions, 8-OHdG formation] and in cell proliferation and apoptosis. After 24 h of treatment, lycopene significantly reduced the increase in ROS production and in 8-OHdG formation induced by the oxysterol in a dose-dependent manner. Moreover, the carotenoid strongly prevented the increase of NOX-4, hsp70 and hsp90 expressions as well as the phosphorylation of the redox-sensitive p38, JNK and ERK1/2 induced by the oxysterol. The attenuation of 7-KC-induced oxidative stress by lycopene coincided with a normalization of cell growth in human macrophages. Lycopene prevented the arrest in G0/G1 phase of cell cycle induced by the oxysterol and counteracted the increased expression of p53 and p21. Concomitantly, it inhibited 7-KC-induced apoptosis, by limiting caspase-3 activation and the modulatory effects of 7-KC on AKT, Bcl-2, Bcl-xL and Bax. Comparing the effects of lycopene, β-carotene and (5Z)-lycopene on ROS production, cell growth and apoptosis show that lycopene and its isomer were more effective than β-carotene in counteracting the dangerous effects of 7-KC in human macrophages. Our study suggests that lycopene may act as a potential antiatherogenic agent by preventing 7-KC-induced oxidative stress and apoptosis in human macrophages. 相似文献
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Anna Scanu Francesca Oliviero Lyssia Gruaz Paolo Sfriso Assunta Pozzuoli Federica Frezzato Carlo Agostini Danielle Burger Leonardo Punzi 《Arthritis research & therapy》2010,12(1):R23
Introduction
To investigate whether monosodium urate (MSU) crystals induce the production of CCL2 (monocyte chemoattractant protein-1; MCP-1) in human fibroblast-like synoviocytes (FLS) and whether this mechanism would be affected by high-density lipoproteins (HDL). 相似文献17.
Crawford DK Trudell JR Bertaccini EJ Li K Davies DL Alkana RL 《Journal of neurochemistry》2007,102(6):2097-2109
Considerable evidence indicates that ethanol acts on specific residues in the transmembrane domains of glycine receptors (GlyRs). In this study, we tested the hypothesis that the extracellular domain is also a target for ethanol action by investigating the effect of cysteine substitutions at positions 52 (extracellular domain) and 267 (transmembrane domain) on responses to n-alcohols and propyl methanethiosulfonate (PMTS) in alpha1GlyRs expressed in Xenopus oocytes. In support of the hypothesis: (i) The A52C mutation changed ethanol sensitivity compared to WT GlyRs; (ii) PMTS produced irreversible alcohol-like potentiation in A52C GlyRs; and (iii) PMTS binding reduced the n-chain alcohol cutoff in A52C GlyRs. Further studies used PMTS binding to cysteines at positions 52 or 267 to block ethanol action at one site in order to determine its effect at other site(s). In these situations, ethanol caused negative modulation when acting at position 52 and positive modulation when acting at position 267. Collectively, these findings parallel the evidence that established the TM domain as a target for ethanol, suggest that positions 52 and 267 are part of the same alcohol pocket and indicate that the net effect of ethanol on GlyR function reflects the summation of its positive and negative modulatory effects on different targets. 相似文献
18.
AIMS: Verify the presence and the molecular identity of phytoplasmas in Northern and Central Italy vineyards where yellows diseases are widespread. METHODS AND RESULTS: Phytoplasma presence and identity were determined by PCR/RFLP analyses on 16S ribosomal gene testing 1424 symptomatic samples. The 65% of samples resulted phytoplasma infected; in particular 256 samples were found positive to phytoplasmas belonging to group 16SrV (mainly Flavescence dorée associated), and the remaining 37% was infected by phytoplasmas belonging to ribosomal subgroup 16SrXII-A (Stolbur or Bois Noir associated). 16SrV ribosomal group representative strains were further typed for variability in SecY and rpS3 genes. The results showed the presence of phytoplasmas belonging to 16SrV-C, 16SrV-D and to a lesser extent, 16SrV-A subgroup. CONCLUSIONS: Possible relationships between genetic polymorphisms of phytoplasma strains belonging to subgroup 16SrV-C and their geographic distribution and/or epidemic situations were detected. SIGNIFICANCE AND IMPACT OF THE STUDY: Bois Noir and Flavescence dorée phytoplasmas are present in significant percentages in the areas under investigation. Molecular tools allowed to identify phytoplasma-infected plants and the genes employed as polymorphism markers resulted useful in distinguishing and monitoring the spreading of the diseases associated with diverse phytoplasmas belonging to 16SrV subgroup in vineyards. 相似文献
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Balestrieri E Pizzimenti F Ferlazzo A Giofrè SV Iannazzo D Piperno A Romeo R Chiacchio MA Mastino A Macchi B 《Bioorganic & medicinal chemistry》2011,19(6):2084-2089
The effects of an extract from Citrus bergamia (BSext) and those of two products purified from the same extract, that is, nomilin and limonin, and reference compounds, towards HTLV-1 have been reported. Moreover, they were also compared with those obtained towards HIV-1. Results showed that the efficacy of both BSext and limonin in inhibiting HTLV-1 as well as HIV-1 expression in infected cells, as evaluated by comparable quantitative assays, was close to that of the effective, reference compounds, respectively. The protective effect of BSext and of the purified products was associated with the inhibition of both HTLV-1 and HIV-1 RT activities in conceptually similar, cell-free assays. The cytotoxicity of the assayed compounds of natural origin was substantially less pronounced than that of the reference compounds, thus showing a favourable selectivity index for the novel BSext product. 相似文献