369 research outputs found
Effect of remobinant granulocyte-macrophage colony stimulating factor (GM-CSF) on leukopenia in AIDS
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Transplantation of progenitor cells and regeneration enhancement in acute myocardial infarction - (TOPCARE-AMI)
Background - Experimental studies suggest that transplantation of blood-derived or bone marrow–derived progenitor cells beneficially affects postinfarction remodeling. The safety and feasibility of autologous progenitor cell transplantation in patients with ischemic heart disease is unknown
Elevated levels of diesel range organic compounds in groundwater near Marcellus gas operations are derived from surface activities
Author Posting. © The Author(s), 2015. This is the author's version of the work. It is posted here by permission of National Academy of Sciences for personal use, not for redistribution. The definitive version was published in Proceedings of the National Academy of Sciences of the United States of American 112 (2015): 13184-13189, doi: 10.1073/pnas.1511474112
.Hundreds of organic chemicals are utilized during natural gas extraction via high volume
hydraulic fracturing (HVHF). However, it is unclear if these chemicals, injected into deep
shale horizons, reach shallow groundwater aquifers and impact local water quality, either
from deep underground injection sites or from the surface or shallow subsurface. Here,
we report detectable levels of organic compounds in shallow groundwater samples from
private residential wells overlying the Marcellus Shale in northeastern Pennsylvania.
Analyses of purgeable and extractable organic compounds from 64 groundwater samples
revealed trace levels of volatile organic compounds, well below the Environmental
Protection Agency’s maximum contaminant levels, and low levels of both gasoline range
(GRO; 0-8 ppb) and diesel range organic compounds (DRO; 0-157 ppb). A compound-specific analysis revealed the presence of bis(2-ethylhexyl)phthalate, which is a disclosed
HVHF additive, that was notably absent in a representative geogenic water sample and
field blanks. Pairing these analyses with 1) inorganic chemical fingerprinting of deep
saline groundwater, 2) characteristic noble gas isotopes, and 3) spatial relationships
between active shale gas extraction wells and wells with disclosed environmental health
and safety (EHS) violations, we differentiate between a chemical signature associated
with naturally occurring saline groundwater and a one associated with alternative
anthropogenic routes from the surface (e.g., accidental spills or leaks). The data support a
transport mechanism of DRO to groundwater via accidental release of fracturing fluid
chemicals derived from the surface rather than subsurface flow of these fluids from the
underlying shale formation.The authors thank Duke University’s Pratt School of Engineering
and the National Science Foundation’s CBET Grant Number 1336702 and NSF EAGER
(EAR-1249255) for financial support.2016-04-1
Combining geostatistical and biotic interaction modelling to predict amphibian refuges under crayfish invasion across dendritic stream networks
Biodiversity ResearchAim: Biological invasions are pervasive in freshwater ecosystems, often causing native
species to contract into areas that remain largely free from invasive species impacts.
Predicting the location of such ecological refuges is challenging, because they
are shaped by the habitat requirements of native and invasive species, their biotic
interactions, and the spatial and temporal invasion patterns. Here, we investigated
the spatial distribution and environmental drivers of refuges from invasion in river
systems, by considering biotic interactions in geostatistical models accounting for
stream network topology. We focused on Mediterranean amphibians negatively impacted
by the invasive crayfishes Procambarus clarkii and Pacifastacus leniusculus.
Location: River Sabor, NE Portugal.
Methods: We surveyed amphibians at 168 200-m stream stretches in 2015.
Geostatistical models were used to relate the probabilities of occurrence of each species
to environmental and biotic variables, while controlling for linear (Euclidean) and
hydrologic spatial dependencies. Biotic interactions were specified using crayfish probabilities
of occurrence extracted from previously developed geostatistical models.
Models were used to map the distribution of potential refuges for the most common
amphibian species, under current conditions and future scenarios of crayfish expansion.
Results: Geostatistical models were produced for eight out of 10 species detected,
of which five species were associated with lower stream orders and only one species
with higher stream orders. Six species showed negative responses to one or
both crayfish species, even after accounting for environmental effects and spatial dependencies.
Most amphibian species were found to retain large expanses of potential
habitat in stream headwaters, but current refuges will likely contract under plausible
scenarios of crayfish expansion.
Main conclusions: Incorporating biotic interactions in geostatistical modelling provides a
practical and relatively simple approach to predict present and future distributions of refuges
from biological invasion in stream networks. Using this approach, our study shows
that stream headwaters are key amphibian refuges under invasion by alien crayfishinfo:eu-repo/semantics/publishedVersio
Environmental and Parental Influences on Offspring Health and Growth in Great Tits (Parus major)
PMCID: PMC3728352This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Coalescent-based species delimitation in the sand lizards of the Liolaemus wiegmannii complex (Squamata: Liolaemidae)
Coalescent-based algorithms coupled with the access to genome-wide data have become powerful tools forassessing questions on recent or rapid diversification, as well as delineating species boundaries in the absence of reciprocal monophyly. In southern South America, the diversification of Liolaemus lizards during the Pleistocene is well documented and has been attributed to the climatic changes that characterized this recent period of time. Past climatic changes had harsh effects at extreme latitudes, including Patagonia, but habitat changes at intermediate latitudes of South America have also been recorded, including expansion of sand fields over northern Patagonia and Pampas). In this work, we apply a coalescent-based approach to study the diversification of the Liolaemus wiegmannii species complex, a morphologically conservative clade that inhabits sandy soils across northwest and south-central Argentina, and the south shores of Uruguay. Using four standard sequence markers (mitochondrial DNA and three nuclear loci) along with ddRADseq data we inferred species limits and a time calibrated species tree for the L. wiegmannii complex in order to evaluate the influence of Quaternary sand expansion/retraction cycles on diversification. We also evaluated the evolutionary independence of the recently described L. gardeli and inferred its phylogenetic position relative to L. wiegmannii. We find strong evidence for six allopatric candidate species within L. wiegmannii, which diversified during the Pleistocene. The Great Patagonian Glaciation (∼1 million years before present) likely split the species complex into two main groups: one composed of lineages associated with sub-Andean sedimentary formations, and the other mostly related to sand fields in the Pampas and northern Patagonia. We hypothesize that early speciation within L. wiegmannii was influenced by the expansion of sand dunes throughout central Argentina and Pampas. Finally, L. gardeli is supported as a distinct lineage nested within the L. wiegmannii complex.Fil: Villamil, Joaquín. Universidad de la República. Facultad de Ciencias; UruguayFil: Avila, Luciano Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico para el Estudio de los Ecosistemas Continentales; ArgentinaFil: Morando, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico para el Estudio de los Ecosistemas Continentales; ArgentinaFil: Sites, Jack W.. University Brigham Young; Estados UnidosFil: Leaché, Adam D.. University of Washington; Estados UnidosFil: Maneyro, Raúl. Universidad de la República. Facultad de Ciencias; UruguayFil: Camargo Bentaberry, Arley. Universidad de la República; Urugua
Blinatumomab vs historical standard therapy of adult relapsed/refractory acute lymphoblastic leukemia
We compared outcomes from a single-arm study of blinatumomab in adult patients with B-precursor Ph-negative relapsed/refractory acute lymphoblastic leukemia (R/R ALL) with a historical data set from Europe and the United States. Estimates of complete remission (CR) and overall survival (OS) were weighted by the frequency distribution of prognostic factors in the blinatumomab trial. Outcomes were also compared between the trial and historical data using propensity score methods. The historical cohort included 694 patients with CR data and 1112 patients with OS data compared with 189 patients with CR and survival data in the blinatumomab trial. The weighted analysis revealed a CR rate of 24% (95% CI: 20-27%) and a median OS of 3.3 months (95% CI: 2.8-3.6) in the historical cohort compared with a CR/CRh rate of 43% (95% CI: 36-50%) and a median OS of 6.1 months (95% CI: 4.2-7.5) in the blinatumomab trial. Propensity score analysis estimated increased odds of CR/CRh (OR=2.68, 95% CI: 1.67-4.31) and improved OS (HR=0.536, 95% CI: 0.394-0.730) with blinatumomab. The analysis demonstrates the application of different study designs and statistical methods to compare novel therapies for R/R ALL with historical data
Clinical and molecular characterization of early T-cell precursor leukemia: a high-risk subgroup in adult T-ALL with a high frequency of FLT3 mutations
A subgroup of pediatric acute T-lymphoblastic leukemia (T-ALL) was characterized by a gene expression profile comparable to that of early T-cell precursors (ETPs) with a highly unfavorable outcome. We have investigated clinical and molecular characteristics of the ETP-ALL subgroup in adult T-ALL. As ETP-ALL represents a subgroup of early T-ALL we particularly focused on this cohort and identified 178 adult patients enrolled in the German Acute Lymphoblastic Leukemia Multicenter studies (05/93–07/03). Of these, 32% (57/178) were classified as ETP-ALL based on their characteristic immunophenotype. The outcome of adults with ETP-ALL was poor with an overall survival of only 35% at 10 years, comparable to the inferior outcome of early T-ALL with 38%. The molecular characterization of adult ETP-ALL revealed distinct alterations with overexpression of stem cell-related genes (BAALC, IGFBP7, MN1, WT1). Interestingly, we found a low rate of NOTCH1 mutations and no FBXW7 mutations in adult ETP-ALL. In contrast, FLT3 mutations, rare in the overall cohort of T-ALL, were very frequent and nearly exclusively found in ETP-ALL characterized by a specific immunophenotype. These molecular characteristics provide biologic insights and implications with respect to innovative treatment strategies (for example, tyrosine kinase inhibitors) for this high-risk subgroup of adult ETP-ALL
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