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51.
Sara Benedetti  Pia Bernasconi  Enrico Bertini  Elena Biagini  Giuseppe Boriani  Cristina Capanni  Nicola Carboni  Giovanna Cenacchi  Marta Columbaro  Monica D’Adamo  Adele D’Amico  Maria Rosaria D’Apice  Marianna Fontana  Alessandra Gambineri  Giovanna Lattanzi  Rocco Liguori  Nadir M Maraldi  Laura Mazzanti  Eugenio Mercuri  Tiziana Mongini  Lucia O Morandi  Iria Neri  Giovanni Nigro  Giuseppe Novelli  Michela Ortolani  Renato Pasquali  Antonella Pini  Stefania Petrini  Luisa Politano  Stefano Previtali  Lisa Pucci  Claudio Rapezzi  Giulia Ricci  Carmelo Rodolico  Paolo Sbraccia  Emanuela Scarano  Gabriele Siciliano  Stefano Squarzoni  Antonio Toscano  Liliana Vercelli  Matteo Ziacchi 《Orphanet journal of rare diseases》2012,7(1):1-3
The need for a collaborative approach to complex inherited diseases collectively referred to as laminopathies, encouraged Italian researchers, geneticists, physicians and patients to join in the Italian Network for Laminopathies, in 2009. Here, we highlight the advantages and added value of such a multidisciplinary effort to understand pathogenesis, clinical aspects and try to find a cure for Emery-Dreifuss muscular dystrophy, Mandibuloacral dysplasia, Hutchinson-Gilford Progeria and forms of lamin-linked cardiomyopathy, neuropathy and lipodystrophy.  相似文献   
52.
Coexistence in ecological communities is governed largely by the nature and intensity of species interactions. Countless studies have proposed methods to infer these interactions from empirical data, yet models parameterised using such data often fail to recover observed coexistence patterns. Here, we propose a method to reconcile empirical parameterisations of community dynamics with species‐abundance data, ensuring that the predicted equilibrium is consistent with the observed abundance distribution. To illustrate the approach, we explore two case studies: an experimental freshwater algal community and a long‐term time series of displacement in an intertidal community. We demonstrate how our method helps recover observed coexistence patterns, capture the core dynamics of the system, and, in the latter case, predict the impacts of experimental extinctions. Collectively, these results demonstrate an intuitive approach for reconciling observed and empirical data, improving our ability to explore the links between species interactions and coexistence in natural systems.  相似文献   
53.
We present a global assessment of the relationships between the short‐wave surface albedo of forests, derived from the MODIS satellite instrument product at 0.5° spatial resolution, with simulated atmospheric nitrogen deposition rates (Ndep), and climatic variables (mean annual temperature Tm and total annual precipitation P), compiled at the same spatial resolution. The analysis was performed on the following five forest plant functional types (PFTs): evergreen needle‐leaf forests (ENF); evergreen broad‐leaf forests (EBF); deciduous needle‐leaf forests (DNF); deciduous broad‐leaf forests (DBF); and mixed‐forests (MF). Generalized additive models (GAMs) were applied in the exploratory analysis to assess the functional nature of short‐wave surface albedo relations to environmental variables. The analysis showed evident correlations of albedo with environmental predictors when data were pooled across PFTs: Tm and Ndep displayed a positive relationship with forest albedo, while a negative relationship was detected with P. These correlations are primarily due to surface albedo differences between conifer and broad‐leaf species, and different species geographical distributions. However, the analysis performed within individual PFTs, strengthened by attempts to select ‘pure’ pixels in terms of species composition, showed significant correlations with annual precipitation and nitrogen deposition, pointing toward the potential effect of environmental variables on forest surface albedo at the ecosystem level. Overall, our global assessment emphasizes the importance of elucidating the ecological mechanisms that link environmental conditions and forest canopy properties for an improved parameterization of surface albedo in climate models.  相似文献   
54.
55.

Objective

In a previous study, we reported the upregulation of Nerve Growth Factor (NGF) and trkANGFR expression in Ocular Cicatricial Pemphigoid (OCP), an inflammatory and remodeling eye disease. Herein, we hypothesize a potential NGF-driven mechanism on fibroblasts (FBs) during OCP remodeling events. To verify, human derived OCP-FBs were isolated and characterized either at baseline or after NGF exposure.

Materials and Methods

Conjunctival biopsies were obtained from 7 patients having OCP and 6 control subjects (cataract surgery). Both conjunctivas and primary FB cultures were characterised for αSMA, NGF and trkANGFR/p75NTR expression. Subcultures were exposed to NGF and evaluated for αSMA, NGF, trkANGFR/p75NTR expression as well as TGFβ1/IL4 release. For analysis, early and advanced subgroups were defined according to clinical parameters.

Results

OCP-conjunctivas showed αSMA-expressing FBs and high NGF levels. Advanced OCP-FBs showed higher αSMA expression associated with higher p75NTR and lower trkANGFR expression, as compared to early counterparts. αSMA expression was in keeping with disease severity and correlated to p75NTR. NGF exposure did not affect trkANGFR levels in early OCP-FBs while decreased both αSMA/p75NTR expression and TGFβ1/IL4 release. These effects were not observed in advanced OCP-FBs.

Conclusions

Taken together, these data are suggestive for a NGF/p75NTR task in the potential modulation of OCP fibrosis and encourages further studies to fully understand the underlying mechanism occurring in fibrosis. NGF/p75NTR might be viewed as a potential therapeutic target.  相似文献   
56.
We investigated the potential plant growth-promoting traits of 377 culturable endophytic bacteria, isolated from Vitis vinifera cv. Glera, as good biofertilizer candidates in vineyard management. Endophyte ability in promoting plant growth was assessed in vitro by testing ammonia production, phosphate solubilization, indole-3-acetic acid (IAA) and IAA-like molecule biosynthesis, siderophore and lytic enzyme secretion. Many of the isolates were able to mobilize phosphate (33%), release ammonium (39%), secrete siderophores (38%) and a limited part of them synthetized IAA and IAA-like molecules (5%). Effects of each of the 377 grapevine beneficial bacteria on Arabidopsis thaliana root development were also analyzed to discern plant growth-promoting abilities (PGP) of the different strains, that often exhibit more than one PGP trait. A supervised model-based clustering analysis highlighted six different classes of PGP effects on root architecture. A. thaliana DR5::GUS plantlets, inoculated with IAA-producing endophytes, resulted in altered root growth and enhanced auxin response. Overall, the results indicate that the Glera PGP endospheric culturable microbiome could contribute, by structural root changes, to obtain water and nutrients increasing plant adaptation and survival. From the complete cultivable collection, twelve promising endophytes mainly belonging to the Bacillus but also to Micrococcus and Pantoea genera, were selected for further investigations in the grapevine host plants towards future application in sustainable management of vineyards.  相似文献   
57.
Recently, dated phylogenies have been increasingly used for ecological studies on community structure and conservation planning. There is, however, a major impediment to a systematic application of phylogenetic methods in ecology: reliable phylogenies with time-calibrated branch lengths are lacking for a large number of taxonomic groups and this condition is likely to continue for a long time. A solution for this problem consists in using undated phylogenies or taxonomic hierarchies as proxies for dated phylogenies. Nonetheless, little is known on the potential loss of information of these approaches compared to studies using dated phylogenies with time-calibrated branch lengths. The aim of this study is to ask how the use of undated phylogenies and taxonomic hierarchies biases a very simple measure of diversity, the mean pairwise phylogenetic distance between community species, compared to the diversity of dated phylogenies derived from the freely available software Phylomatic. This is illustrated with three sets of data on plant species sampled at different scales. Our results show that: (1) surprisingly, the diversity computed from dated phylogenies derived from Phylomatic is more strongly related to the diversity computed from taxonomic hierarchies than to the diversity computed from undated phylogenies, while (2) less surprisingly, the strength of this relationship increases if we consider only angiosperm species.  相似文献   
58.
A total of 242 larval forms of Anisakis collected from marine fishes at different sites off the Moroccan and Mauritanian coasts, recognised as belonging to Type I and Type II larvae, were identified by PCR-RFLP (Polymerase Chain Reaction-Restriction Fragment Length Polymorphisms) of the ITS (Internal Transcribed Spacers) region (ITS-1, 5.8 subunit rRNA gene and ITS-2), using a previously established molecular key. The Type I larvae were found with a frequency of 98.34% and were identified as belonging to the following species: A. simplex s.str., A. pegreffii, A. simplex s.str/A. pegreffii heterozygote genotypes, A. typica, A. ziphidarum and Anisakis sp. A. The Type II larvae were found to belong to A. physeteris, with the frequency of 1.65%. The results reported in the present study provide further epizootiological and biological data on the Anisakis spp. in marine fishes off the Moroccan and Mauritanian coasts, improving the picture of the occurrence of these species in the central Atlantic coasts.  相似文献   
59.
A simple method for the quantification of tipranavir, the first non-peptidic HIV protease inhibitor, was developed and validated. Quinoxaline, as internal standard, was added to 50 microl of plasma before a liquid-liquid extraction by 600 microl of protein precipitation solution. The extracts were diluted before being injected in the chromatographic system. Chromatographic separation was made on a C18 column using potassium phosphate buffer (pH 3.2) and acetonitrile with gradient. Detection was performed by an UV detector at 260 nm. Relative error at three control quality concentrations ranged from -1.81 to 1.72%. Intra-day (CV%) and inter-day (CV%) precision ranged from 0.94 to 2.55% and from 3.07 to 4.24%, respectively. LOQ and LOD were 0.090 microg/ml and 0.035 microg/ml, respectively. Mean recovery was 87.1%+/-2.4%. Calibration curve was linear up to 180 microg/ml. Concentration range when optimized (0.703-180 microg/ml) proved to be adequate to measure tipranavir concentration in HIV-1-positive patients, therefore this method could be suitable for therapeutic drug monitoring of this drug.  相似文献   
60.
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