79 research outputs found

    Degradation of the polyamine alkaloid aphelandrine by endophytic fungi isolated from Aphelandra tetragona

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    Members of the genus Aphelandra (Acanthaceae) produce rare macrocyclic polyamine alkaloids which consist of spermine acylated with two units of 3-(4-hydroxyphenyl)prop-2-enoic acid. Endophytic fungi were isolated from roots and shoots of Aphelandra tetragona and tested for their ability to metabolize the main alkaloid aphelandrine, which accumulates exclusively in the roots of the plants. Several endophytes were able to metabolize aphelandrine but only root endophytes belonging to the Nectriaceae were good metabolizers. In addition, the endophytes were grown on an agar medium containing putrescine, spermidine, or spermine as the sole nitrogen source. All fungi were able to grow on putrescine, but only the good aphelandrine metabolizers grew well on spermidine or spermine. Acremonium sp. 15, one of the most active metabolizers, grew also on a medium containing aphelandrine as sole nitrogen source. A number of strains thought to be conspecific with Acremonium sp. 15 were also tested for their ability to metabolize aphelandrine. The ability of the endophytes to metabolize aphelandrine suggests an ecological adaptation of the symbionts to their host. The possibility of using the aphelandrine metabolism as a taxonomic character is briefly discusse

    Identification of dermatophytes by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry

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    In this study we evaluated the suitability of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for the identification of dermatophytes in diagnostic laboratories. First, a spectral database was built with 108 reference strains belonging to 18 species of the anamorphic genera Epidermophyton, Microsporum and Trichophyton. All strains were well characterized by morphological criteria and ITS sequencing (gold standard). The dendrogram resulting from MALDI-TOF mass spectra was almost identical with the phylogenetic tree based on ITS sequencing. Subsequently, MALDI-TOF MS SuperSpectra were created for the identification of Epidermophyton floccosum, Microsporium audouinii, M. canis, M. gypseum (teleomorph: Arthroderma gypseum), M. gypseum (teleomorph: A. incurvatum), M. persicolor, A. benhamiae (Tax. Entity 3 and Am-Eur. race), T. erinacei, T. interdigitale (anthropophilic and zoophilic populations), T. rubrum/T. violaceum, T. tonsurans and T. terrestre. Because T. rubrum and T. violaceum did not present enough mismatches, a SuperSpectrum covering both species was created, and differentiation between them was done by comparison of eight specific peptide masses. In the second part of this study, MALDI-TOF MS with the newly created SuperSpectra was tested using 141 clinical isolates representing nine species. Analyses were done with 3-day-old cultures. Results were compared to morphological identification and ITS sequencing; 135/141 (95.8%) strains were correctly identified by MALDI-TOF MS compared to 128/141 (90.8%) by morphology. Therefore, MALDI-TOF MS has proven to be a useful and rapid identification method for dermatophyte

    Chronic venous disorders: Correlation between visible signs, symptoms, and presence of functional disease

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    none5siBackground: The aim of this study was to investigate the frequency of chronic venous disorders (CVD) in different demographic groups in Italy and to provide correlations between patterns of valve incompetence and clinical feature of disease severity. Methods: Advertisements in television and newspapers in 53 Italian cities were used to solicit 16,251 subjects (13,826 women, mean age 50.4 years; 2,425 men, mean age 59.1 years). They underwent a clinical examination of the lower limbs, including presence and severity of visible signs (CEAP classification), and assessment of functional disease by color-coded duplex ultrasound imaging. Results: Varicose veins and telangiectases were the most common objective signs in both men and women. Older people were more severely affected. Telangiectases were more frequent in women, and men had a higher incidence of trunk varices, trophic changes, and venous reflux. Frequency of both visible and functional venous disease increased with family history and body mass index. Presence of reflux correlated positively with increasing CEAP grade of visible disease (P for trend < .0001 for all superficial venous segments). A large number of subjects, especially women, complained of subjective symptoms in the legs, and the presence of symptoms correlated almost always positively with both worsening of visible findings (P for trend < .001) and presence of hemodynamic change in both genders. Conclusions: The frequency of reflux increased with the severity of visible signs of disease as described by the CEAP classification. In men, the occurrence of subjective symptoms was mostly correlated with functional disorders. © 2007 The Society for Vascular Surgery.Chiesa, R.; Marone, E.M.; Limoni, C.; Volontè, M.; Petrini, O.Chiesa, R.; Marone, ENRICO MARIA; Limoni, C.; Volontè, M.; Petrini, O

    Chemical elements in Ascomycetes and Basidiomycetes - The reference mushrooms as instruments for investigating bioindication and biodiversity

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    Fungi in the wild are among the principal agents in biogeochemical cycles; those cycles of matter and energy that enable ecosystems to work. By investigating the biodiversity of Italian fungal species and concentration levels of chemical elements in them, it may be possible to use these fungi as biological indicators for the quality of forest, woodland and semi-natural environments. The database of this EUR Report record the dry-material concentrations of 35 chemical elements, including heavy metals, in over 9,000 samples of higher mushrooms (Ascomycetes and Basidiomycetes). These samples represent approximately 200 genera and a thousand species. As the database has attained statistical stability it has been possible to define the concept of a “reference mushroom”. The use of a “reference mushroom” may benefit – perhaps only as a methodological approach – various fields of mycological and environmental research; from biodiversity and bioindication, through taxonomy right up to health and sanitation issues. The sheer volume of the collected data may prove to be useful as a comparison for data collected in the future; such results would also allow a better and more exhaustive interpretation of the effects of environmental protection laws that have been in place over the years to reduce or remedy current climate change phenomena and the environmental damage caused by human activity. Studies pertaining to the frequency of occurrence and the ecology of the various fungal species found on Italian soil have tended to link the reference habitats used to European classification guidelines (Natura 2000, CORINE Land Cover, CORINE Biotopes and EUNIS). Thereby the foundations have been laid for the use of mushrooms as biological indicators for the measurement of soil and ecosystem quality.JRC.DDG.H.5-Rural, water and ecosystem resource

    Correlating Fluorescence and High-Resolution Scanning Electron Microscopy (HRSEM) for the study of GABAA receptor clustering induced by inhibitory synaptic plasticity

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    Both excitatory and inhibitory synaptic contacts display activity dependent dynamic changes in their efficacy that are globally termed synaptic plasticity. Although the molecular mechanisms underlying glutamatergic synaptic plasticity have been extensively investigated and described, those responsible for inhibitory synaptic plasticity are only beginning to be unveiled. In this framework, the ultrastructural changes of the inhibitory synapses during plasticity have been poorly investigated. Here we combined confocal fluorescence microscopy (CFM) with high resolution scanning electron microscopy (HRSEM) to characterize the fine structural rearrangements of post- synaptic GABAA Receptors (GABAARs) at the nanometric scale during the induction of inhibitory long-term potentiation (iLTP). Additional electron tomography (ET) experiments on immunolabelled hippocampal neurons allowed the visualization of synaptic contacts and confirmed the reorganization of post- synaptic GABAAR clusters in response to chemical iLTP inducing protocol. Altogether, these approaches revealed that, following the induction of inhibitory synaptic potentiation, GABAAR clusters increase in size and number at the post-synaptic membrane with no other major structural changes of the pre- and post-synaptic elements

    Plasmid-mediated quinolone resistance in Aeromonas allosaccharophila recovered from a Swiss lake

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    Objectives To search for plasmid-mediated qnr genes among waterborne environmental Aeromonas spp. recovered from Switzerland. Methods Isolates presenting MICs of nalidixic acid or ciprofloxacin ≥1 mg/L were screened for qnr genes by a multiplex PCR approach followed by sequencing. Plasmids were transferred by transformation, and further analysis of the genetic structures surrounding the qnrS2 gene was carried out by PCR and sequencing. Results A qnrS2 gene was identified from a single Aeromonas allosaccharophila isolate (Lugano lake, Lugano), as part of a mobile insertion cassette located on a broad host range IncU-type plasmid. This plasmid co-harboured a class 1 integron containing the aac(6′)-Ib-cr, blaOXA-1, catB3 and arr-3 gene cassettes. Conclusions These findings strengthen further the role of Aeromonas spp. as a reservoir of antimicrobial resistance determinants in the environmen

    Cognitive Performance and Morning Levels of Salivary Cortisol and α-Amylase in Children Reporting High vs. Low Daily Stress Perception

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    The aim of the present study was to assess the effects of daily stress perception on cognitive performance and morning basal salivary cortisol and alpha-amylase levels in healthy children aged 9-12. Participants were classified by whether they had low daily perceived stress (LPS, n = 27) or a high daily perceived stress (HPS, n = 26) using the Children Daily Stress Inventory (CDSI). Salivary cortisol and alpha-amylase were measured at awakening and 30 minutes later. Cognitive performance was assessed using the Cognitive Drug Research assessment system. The HPS group exhibited significantly poorer scores on speed of memory (p < .05) and continuity of attention (p < .05) relative to the LPS group. The HPS group also showed significantly lower morning cortisol levels at awakening and at +30 minutes measures in comparison with the LPS group (p < .05), and mean morning cortisol levels were negatively correlated with speed of memory (p < .05) in the 53 participants. No significant differences were observed between both groups in alpha-amylase levels. These findings suggest that daily perceived stress in children may impoverish cognitive performance via its modulating effects on the HPA axis activit

    Rapid characterization of aquatic hyphomycetes by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry

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    Protein fingerprinting using matrix-assisted laser desorption/ionization time-of-flight mass spec-trometry (MALDI-TOF MS) is a rapid, reliable, and economical method to characterize isolates of terrestrial fungi and other microorganisms. The objective of our study was to evaluate the suitability of MALDI-TOF MS for the identification of aquatic hyphomycetes, a polyphyletic group of fungi that play crucial roles in stream ecosystems. To this end, we used 34 isolates of 21 aquatic hyphomycete species whose identity was confirmed by spore morphology and internal transcribed spacer (ITS1-5.8S-ITS2 = ITS) nuc rDNA sequencing. We tested the efficiency of three protein extraction methods, including chemical and mechanical treatments using 13 different protocols, with the objective of producing high-quality MALDI-TOF mass spectra. In addition to extraction protocols, mycelium age was identified as a key parameter affecting protein extraction efficiency. The dendrogram based on mass-spectrum similarity indicated good and relevant taxonomic discrimination; the tree structure was comparable to that of the phylogram based on ITS sequences. Consequently, MALDI-TOF MS could reliably identify the isolates studied and provided greater taxonomic accuracy than classical morphological methods. MALDI-TOF MS seems suited for rapid characterization and identification of aquatic hyphomycete species

    Choice of costimulatory domains and of cytokines determines CAR T-cell activity in neuroblastoma

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    Chimeric antigen receptor (CAR) T-cell therapy has been shown to be dramatically effective in the treatment of B-cell malignancies. However, there are still substantial obstacles to overcome, before similar responses can be achieved in patients with solid tumors. We evaluated both in vitro and in a preclinical murine model the efficacy of different 2nd and 3rd generation CAR constructs targeting GD2, a disial-ganglioside expressed on the surface of neuroblastoma (NB) tumor cells. In order to address potential safety concerns regarding clinical application, an inducible safety switch, namely inducible Caspase-9 (iC9), was also included in the vector constructs. Our data indicate that a 3rd generation CAR incorporating CD28.4-1BB costimulatory domains is associated with improved anti-tumor efficacy as compared with a CAR incorporating the combination of CD28.OX40 domains. We demonstrate that the choice of 4-1BB signaling results into significant amelioration of several CAR T-cell characteristics, including: 1) T-cell exhaustion, 2) basal T-cell activation, 3) in vivo tumor control and 4) T-cell persistence. The fine-tuning of T-cell culture conditions obtained using IL7 and IL15 was found to be synergic with the CAR.GD2 design in increasing the anti-tumor activity of CAR T cells. We also demonstrate that activation of the suicide gene iC9, included in our construct without significantly impairing neither CAR expression nor anti-tumor activity, leads to a prompt induction of apoptosis of GD2.CAR T cells. Altogether, these findings are instrumental in optimizing the function of CAR T-cell products to be employed in the treatment of children with NB

    The Trichoderma koningii aggregate species

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    The morphological concept of Trichoderma koningii is found to include several species that differ from each other in details of phenotype (including conidium morphology, growth rate) and biogeography. Phylogenetic analysis utilizing partial sequences of the translation-elongation factor 1 alpha (tef1), as well as fragments of actin and calmodulin genes, indicate that phenotypic characters typical of T. koningii evolved independently in three well-separated main lineages. Combined molecular and phenotype data lead to the development of a taxonomy with the recognition of twelve taxonomic species and one variety within the three lineages. These lineages include: (1) T. koningii and T. ovalisporum and the new species T. caribbaeum var. caribbaeum, T. caribbaeum var. aequatoriale, T. dorotheae, T. dingleyae, T. intricatum, T. koningiopsis, T. petersenii and T. taiwanense; (2) the new species T. rogersonii and T. austrokoningii, and (3) the new anamorph T. stilbohypoxyli
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