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101.
Patient management in Idiopathic Pulmonary Fibrosis (IPF) is largely based on societal guidelines and recommendations. A recent update by the American Thoracic Society (ATS), European Respiratory Society (ERS), Japanese Respiratory Society (JRS) and Latin American Thoracic Association (ALAT) provided updated guidance on the diagnosis and management of IPF, along with recommendations on pharmacologic and non-pharmacologic approaches to patient management. The treatment guidance is based on GRADE criteria, which rates the quality of evidence according to previously published methodology. Here we discuss how to interpret the recent guideline updates and the implications of this guidance for clinical practice. In addition we discuss the assessment and recommendations for a number of pharmacological agents that have been the focus of clinical trials over the past years. Although no single pharmacological agent was recommended by the guidelines committee, we discuss how since then, more recent data have resulted in the approval of pirfenidone in Europe, and preliminary negative findings regarding the safety of a triple therapy regimen consisting of prednisone, azathioprine and N-acetylcysteine have raised the question of whether it is no longer a treatment option. As clinicians, we must interpret the available guidance and recommendations as we consider each individual patient and as we discuss the available clinical data and the patient’s own preferences in our approach to the management of this disease. 相似文献
102.
The possibility of enhancing the ex situ bioremediation of a chronically polychlorinated biphenyl (PCB)-contaminated soil
by using Triton X-100 or Quillaya Saponin, a synthetic and a biogenic surfactant, respectively, was studied. The soil, which
contained about 350 mg/kg of PCBs and indigenous aerobic bacteria capable of growing on biphenyl or on monochlorobenzoic acids,
was amended with inorganic nutrients and biphenyl, saturated with water and treated in aerobic batch slurry- and fixed-phase
reactors. Triton X-100 and Quillaya Saponin were added to the reactors at a final concentration of 10 g/l at the 42nd day
of treatment, and at the 43rd and 100th day, respectively. Triton X-100 was not metabolised by the soil microflora and it
exerted inhibitory effects on the indigenous bacteria. Quillaya Saponin, on the contrary, was readily metabolised by the soil
microflora. Under slurry-phase conditions, Triton X-100 negatively influenced the soil bioremediation process by affecting
the availability of the chlorobenzoic acid degrading indigenous bacteria, whereas Quillaya Saponin slightly enhanced the biological
degradation and dechlorination of the soil PCBs. In the fixed-phase reactors, where both the surfactant availability and the
mixing of the soil were lower, Triton X-100 did not exert inhibitory effects on the soil biomass and enhanced significantly
the soil PCB depletion, whereas Quillaya Saponin did not influence the bioremediation process.
Received: 28 April 1998 / Received last revision: 15 July 1998 / Accepted: 29 July 1998 相似文献
103.
104.
Ambrosi A Glad IK Pellin D Cattoglio C Mavilio F Di Serio C Frigessi A 《PLoS computational biology》2011,7(12):e1002292
Integration of retroviral vectors in the human genome follows non random patterns that favor insertional deregulation of gene expression and may cause risks of insertional mutagenesis when used in clinical gene therapy. Understanding how viral vectors integrate into the human genome is a key issue in predicting these risks. We provide a new statistical method to compare retroviral integration patterns. We identified the positions where vectors derived from the Human Immunodeficiency Virus (HIV) and the Moloney Murine Leukemia Virus (MLV) show different integration behaviors in human hematopoietic progenitor cells. Non-parametric density estimation was used to identify candidate comparative hotspots, which were then tested and ranked. We found 100 significative comparative hotspots, distributed throughout the chromosomes. HIV hotspots were wider and contained more genes than MLV ones. A Gene Ontology analysis of HIV targets showed enrichment of genes involved in antigen processing and presentation, reflecting the high HIV integration frequency observed at the MHC locus on chromosome 6. Four histone modifications/variants had a different mean density in comparative hotspots (H2AZ, H3K4me1, H3K4me3, H3K9me1), while gene expression within the comparative hotspots did not differ from background. These findings suggest the existence of epigenetic or nuclear three-dimensional topology contexts guiding retroviral integration to specific chromosome areas. 相似文献
105.
Sampietro M Bottani CE Carminati M Casari C Castoldi A Ferrari G Fusi M Guazzoni C Rottigni A Vergani M 《IEEE pulse》2011,2(3):35-40
The increase in the understanding of the physical and functional properties of the biological material, from the cellular level down to single molecules, owes its success to the development of suitable high-sensitivity platforms to image the biomaterial and analyze its response to specific stimuli. Imaging has indeed reached molecular capabilities, thanks to optical or magnetic markers [1], to the atomic force microscopy (AFM) in surface reconstruction [2], and is nearing success in three-dimensional (3-D) reconstruction thanks to X-ray holography [3]. 相似文献
106.
107.
Marco Antônio Batalha Igor Aurélio SilvaMarcus Vinicius Cianciaruso Helena FrançaGustavo Henrique de Carvalho 《Flora》2011,206(11):949-956
Soil, drought, and fire are abiotic factors that may act as environmental filters in the cerrado, the Brazilian savanna. We used a framework to analyze environmental filtering in geographic and phylogenetic context, sampling woody species in one of the largest cerrado reserves. In 100 quadrats, we measured 10 functional traits on each woody individual. We also measured several soil variables, altitude and slope as a rough surrogate of water availability, interval between fires, and time since last fire. Almost all environmental variables were spatially auto-correlated. We found an overall trait clustering, but not an overall phylogenetic clustering. Nevertheless, we found a phylogenetic signal for some traits. Linking phylogeny, traits, environment, and space, we were able to detect a major dichotomy between two geomorphological units. The flat tableland was positively related with altitude, fire frequency, and nutrient-richer soil. Environmental filtering caused by water availability and fire lead to trait clustering, with smaller shrubs and trees that presented thicker barks, denser woods, sclerophyllous leaves, highlighted by the prevalance of Myrtaceae. The other geomorphological unit, hilly terrain, was positively related with slope, low fire frequency, and nutrient-poorer soil. Environmental filtering was caused especially by nutrient-poor soil that lead to trait clustering, assembling taller trees, with thinner barks, lighter woods, and compound, large, tender, nutrient-richer leaves, distributed across many lineages, including Fabaceae. Hence, the high environmental variability in space with different environmental filters assembled different combination of plant traits and lineages, increasing the overall diversity in cerrado. 相似文献
108.
Barbara Tomassetti Annalina Lombardi Enzo Cerasani Antonio Di Sabatino Loretta Pace Dina Ammazzalorso Marco Verdecchia 《Aerobiologia》2013,29(1):55-70
Airborne particles (pollens and fungal spores) are recognized as important causes of allergies and many other pathologies whose main symptoms are usually associated with respiratory problems. In addition, these particles seem to be responsible for clinical symptoms of oculorhinitis and bronchial asthma. Many authors showed how pollen and spore concentrations are critically linked to meteorological conditions, while other studies investigated the possibility to estimate these concentrations through meteorological parameters. So, many different approaches have been proposed, and one of the most sophisticated is based on the use of a complex artificial neural network architecture. Once the neural device is calibrated using simultaneous time series of observed meteorological parameters and airborne biological particles, it is straightforward to use the Neural Network to predict spore concentrations using operational Limited Area Meteorological Model. In a previous work, it has been shown that the MM5 meteorological model developed by National Center for Atmospheric Research and Pennsylvania State University can be coupled with the above-cited neural predictor to provide a good prediction of Alternaria and Pleospora spore in the location of L’Aquila (Central Italy). Following the same approach, this work aims to provide the mapping of spore concentration over a wide area covered by high-resolution meteorological prediction in Central Italy. The complex patterns of fungal spore concentrations in selected areas will be described, and the high temporal variability of such fields will be discussed as well. The possibility to infer useful information from the predicted pattern of spore concentrations is discussed, as an example it appears that for people suffering from allergy to fungal spores is more comfortable to spend summertime close to the east coast of Italian Peninsula respect to the west coast. A further step of this work may easily lead to an operational use of the model for supporting the clinical management of allergies and for establishing a preventive strategy in agriculture to avoid unsafe and useless pollution of atmosphere, crops and fields. 相似文献
109.
110.
Luca Luiselli Thomas Madsen Dario Capizzi Lorenzo Rugiero Nic Pacini Massimo Capula 《Ecological Research》2011,26(4):745-753
A review of several long-term studies has recently suggested that snakes might be declining in large parts of the world. Additional data from other long-term studies are therefore urgently needed in order to assess the generalities of such suggested declines. Based on a 20-year study, we analyzed demographic data on adult dice snakes (Natrix tessellata) studied in central Italy between 1985 and 2004. Both male and female dice snakes were relatively long-lived, with no significant differences in longevity between the sexes. Individual males and females were observed over a maximum of 10 and 14 years, respectively. However, the among-year recapture rates between the year the snakes were initially captured and the subsequent year (i.e., year 1 to year 2) was significantly lower (45%) than the among-year recapture rates during subsequent years (74%; i.e., year 2 to year 3), suggesting that a large proportion of the snakes at first capture were in fact not resident within our study area, and hence many snakes were migrating in and out of our 2-km stream study site, with no inter-sexual difference in dispersal rates. Sex ratio was virtually equal if we consider the study period as a whole. Significant annual fluctuations were, however, observed through the study. In 1985–1990, 1993–1995, 1998 and 1999 the sex ratio was male-biased, whereas in 2000–2004 female-biased. In terms of both survival and recapture probabilities, model selection showed that Akaike’s information criterion favored the model incorporating body size, with the model incorporating year having an intermediate likelihood, and the model with sex included being the most disfavored. Total population number estimates suggest an average 86 adult individuals along the 2 km of stream with only minor annual variations. However, a significant decrease in the number of males occurred during the last 6 years of our study. Thus, further monitoring of this population is warranted in light of the decline of snake populations reported recently. 相似文献