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171.
Roberta Battistini Elisa Marcucci Marco Verani Graziano Di Giuseppe Fernando Dini Annalaura Carducci 《European journal of protistology》2013,49(3):381-388
The aim of the present work was to study the dynamics of the interactions between human adenovirus and ciliates under both experimental and field conditions. Experimental co-cultures of the ciliated protozoan Euplotes octocarinatus and human adenovirus (HAdV) type 2 were established and virus internalization was investigated using nested PCR and direct immunofluorescence (IF). In addition, to study protozoa-virus interactions in the field, wild ciliates were isolated from active sludges of a wastewater treatment plant and analyzed for the presence of adenovirus using direct IF. In vitro experiments revealed HAdV type 2 inside Euplotes cells after 15 min of contact and its persistence until at least 35 days post infection. In addition, our results showed the adsorption of adenovirus on the surface of wild ciliates. We conclude that HAdV is taken up by ciliates, however more studies are necessary in order to better investigate the mechanisms, the infectivity of internalized virus and the protective effects of internalization against disinfection. 相似文献
172.
Hirotaka Furukawa Marco Wieser Hiroshi Morita Tsuyoshi Sugio T. Nagasawa 《Archives of microbiology》1998,171(1):37-43
Pseudomonas fluorescens E118 was isolated from soil as an effective eugenol-degrading organism by a screening using eugenol as enrichment substrate.
The first enzyme involved in the degradation of eugenol in this organism, eugenol dehydrogenase, was purified after induction
by eugenol, and the purity of the enzyme was shown by SDS-PAGE and gel-permeation HLPC. The enzyme is a heterodimer that consists
of a 10-kDa cytochrome c and a 58-kDa subunit. The larger subunit presumably contains flavin, suggesting a flavocytochrome c structure and an electron transfer via flavin and cytochrome c during dehydrogenation. The activity of the purified enzyme depended on the addition of a final electron acceptor such as
phenazine methosulfate, 2,6-dichlorophenol-indophenol, cytochrome c, or potassium ferricyanide. The enzyme catalyzed the dehydrogenation of three different 4-hydroxybenzylic structures including
the conversion of eugenol to coniferyl alcohol, 4-alkylphenols to 1-(4-hydroxyphenyl)alcohols, and 4-hydroxybenzylalcohols
to the corresponding aldehydes. The catalytic and structural similarity between this enzyme and a Penicillium vanillyl-alcohol oxidase and 4-alkylphenol methylhydroxylases from several Pseudomonas species is discussed.
Received: 17 June 1998 / Accepted: 12 October 1998 相似文献
173.
Elisa Bisicchia Laura Latini Virve Cavallucci Valeria Sasso Vanessa Nicolin Marco Molinari Marcello D’Amelio Maria Teresa Viscomi 《Molecular neurobiology》2017,54(7):4896-4907
Spinal cord injuries (SCIs) are devastating conditions of the central nervous system (CNS) for which there are no restorative therapies. Neuronal death at the primary lesion site and in remote regions that are functionally connected to it is one of the major contributors to neurological deficits following SCI.Disruption of autophagic flux induces neuronal death in many CNS injuries, but its mechanism and relationship with remote cell death after SCI are unknown. We examined the function and effects of the modulation of autophagy on the fate of axotomized rubrospinal neurons in a rat model of spinal cord dorsal hemisection (SCH) at the cervical level. Following SCH, we observed an accumulation of LC3-positive autophagosomes (APs) in the axotomized neurons 1 and 5 days after injury. Furthermore, this accumulation was not attributed to greater initiation of autophagy but was caused by a decrease in AP clearance, as demonstrated by the build-up of p62, a widely used marker of the induction of autophagy. In axotomized rubrospinal neurons, the disruption of autophagic flux correlated strongly with remote neuronal death and worse functional recovery. Inhibition of AP biogenesis by 3-methyladenine (3-MA) significantly attenuated remote degeneration and improved spontaneous functional recovery, consistent with the detrimental effects of autophagy in remote damage after SCH. Collectively, our results demonstrate that autophagic flux is blocked in axotomized neurons on SCI and that the inhibition of AP formation improves their survival. Thus, autophagy is a promising target for the development of therapeutic interventions in the treatment of SCIs. 相似文献
174.
175.
Salmaso M Malacarne G Troggio M Faes G Stefanini M Grando MS Velasco R 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2008,116(8):1129-1143
Grapevine molecular maps based on microsatellites, AFLP and RAPD markers are now available. SSRs are essential to allow cross-talks
between maps, thus upgrading any growing grapevine maps. In this work, single nucleotide polymorphisms (SNPs) were developed
from coding sequences and from unique BAC-end sequences, and nested in a SSR framework map of grapevine. Genes participating
to flavonoids metabolism and defence, and signal transduction pathways related genes were also considered. Primer pairs for
351 loci were developed from ESTs present on public databases and screened for polymorphism in the “Merzling” (a complex genotype
Freiburg 993–60 derived from multiple crosses also involving wild Vitis species) × Vitis vinifera (cv. Teroldego) cross population. In total 138 SNPs, 108 SSR markers and a phenotypic trait (berry colour) were mapped in
19 major linkage groups of the consensus map. In specific cases, ESTs with putatively related functions mapped near QTLs previously
identified for resistance and berry ripening. Genes related to anthocyanin metabolism mapped in different linkage groups.
A myb gene, which has been correlated with anthocyanin biosynthesis, cosegregated with berry colour on linkage group 2. The possibility
of associating candidate genes to known position of QTL is discussed for this plant.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Marzia Salmaso and Giulia Malacarne contributed equally to the present work. 相似文献
176.
177.
Marilisa Villano Annalisa Borghini Mirko Manetti Erica Gabbrielli Antonella Rossi Piersante Sestini Anna Franca Milia Francesca Nacci Serena Guiducci Marco Matucci-Cerinic Lidia Ibba-Manneschi Elisabetta Weber 《Arthritis research & therapy》2013,15(4):R90
Introduction
Systemic sclerosis (SSc) is a connective tissue disorder characterized by endothelial cell injury, autoimmunity and fibrosis. The following three fibrillin-1 alterations have been reported in SSc. (1) Fibrillin-1 microfibrils are disorganized in SSc dermis. (2) Fibrillin-1 microfibrils produced by SSc fibroblasts are unstable. (3) Mutations in the FBN1 gene and anti-fibrillin-1 autoantibodies have been reported in SSc. Fibrillin-1 microfibrils, which are abundantly produced by blood and lymphatic microvascular endothelial cells (B-MVECs and Ly-MVECs, respectively), sequester in the extracellular matrix the latent form of the potent profibrotic cytokine transforming growth factor β (TGF-β). In the present study, we evaluated the effects of SSc sera on the deposition of fibrillin-1 and microfibril-associated glycoprotein 1 (MAGP-1) and the expression of focal adhesion molecules by dermal B-MVECs and Ly-MVECs.Methods
Dermal B-MVECs and Ly-MVECs were challenged with sera from SSc patients who were treatment-naïve or under cyclophosphamide (CYC) treatment and with sera from healthy controls. Fibrillin-1/MAGP-1 synthesis and deposition and the expression of αvβ3 integrin/phosphorylated focal adhesion kinase and vinculin/actin were evaluated by immunofluorescence and quantified by morphometric analysis.Results
Fibrillin-1 and MAGP-1 colocalized in all experimental conditions, forming a honeycomb pattern in B-MVECs and a dense mesh of short segments in Ly-MVECs. In B-MVECs, fibrillin-1/MAGP-1 production and αvβ3 integrin expression significantly decreased upon challenge with sera from naïve SSc patients compared with healthy controls. Upon challenge of B-MVECs with sera from CYC-treated SSc patients, fibrillin-1/MAGP-1 and αvβ3 integrin levels were comparable to those of cells treated with healthy sera. Ly-MVECs challenged with SSc sera did not differ from those treated with healthy control sera in the expression of any of the molecules assayed.Conclusions
Because of the critical role of fibrillin-1 in sequestering the latent form of TGF-β in the extracellular matrix, its decreased deposition by B-MVECs challenged with SSc sera might contribute to dermal fibrosis. In SSc, CYC treatment might limit fibrosis through the maintenance of physiologic fibrillin-1 synthesis and deposition by B-MVECs. 相似文献178.
Debora Barros Barbosa Douglas Roberto Monteiro Valentim Adelino Ricardo Barão Ana Carolina Pero Marco Antonio Compagnoni 《Gerodontology》2009,26(3):225-231
Background: The fracture between acrylic denture base material and artificial teeth is a common clinical occurrence in dental prosthodontic practice. Objective: To evaluate the bond strength between acrylic resins and resin denture teeth when submitted by two protocols of monomer liquid application on the tooth surface and using different polymerisation methods. Material and methods: Microwave‐polymerised (Onda‐Cryl), heat‐polymerised (Clássico) and autopolymerising (Jet) acrylic resins and a brand of resin denture teeth (Biotone) were used. The acrylic resins were polymerised according to the cycles: (A) microwave – fast cycle, Onda‐Cryl; (B) microwave – long cycle, Onda‐Cryl; (C) microwave – manufacturer’s cycle, Onda‐Cryl; (T) water bath – long cycle, Clássico and (Q) bench polymerisation cycle, Jet. Thirty specimens were prepared for each polymerisation method; 10 were packed with acrylic resin after 60 s of monomer liquid application on the tooth surface, 10 after 180 s and 10 without any monomer liquid application. For the purpose of the study, a shear test was used. anova and Tukey tests were performed to identify significant differences (α = 0.05). Results: The highest bond strength values were found for monomer surface treatments, regardless of the polymerisation cycles. The highest significant values were found for cycles B (15.4 ± 1.8 MPa), C (11.9 ± 4.9 MPa) and T (15.4 ± 2.6 MPa) for non‐treated and 60 s methylmethacrylate treated groups. Comparing the monomer liquid treatment, they did not differ significantly (p > 0.05), except for cycle A (p < 0.05). Conclusion: Chemical treatment using monomer on the tooth surface prior to the acrylic resin packing improved the bond strength between resin denture tooth and acrylic resin, regardless of monomer liquid treatment protocols. The microwavable resin, polymerised by fast cycle and autopolymerising resin should be avoided for processing denture and denture repairs, respectively. 相似文献
179.
Marco Camanni Luca Bonino Elena Maria Delpiano Paola Berchialla Giuseppe Migliaretti Alberto Revelli Francesco Deltetto 《Reproductive biology and endocrinology : RB&E》2009,7(1):109-7
Background
this study aims to evaluate the effectiveness and safety of laparoscopic conservative management of ureteral endometriosis. 相似文献180.
Passeri Elena Bonomi Marco Dangelo Francesco Persani Luca Corbetta Sabrina 《BMC endocrine disorders》2014,14(1):1-4