2,430 research outputs found
Protection of mice against cancer by immunization with membranes but not purified virions from virus infected cancer cells.
The life span of C57/Bl mice inoculated with Lewis lung carcinoma cells was prolonged if the mice were pre-immunized with membranes from these cells infected in vitro with influenza virus. Likewise, BALB/c mice were protected against the malignant tumour WEHI-11 by prior immunization with extracts of cultured WEHI-11 cells which had been infected with influenza virus or Semiliki Forest virus (SFV). Partially purified SFV grown in WEHI-11 cells also protected mice from cancer grafts but neither highly purified SFV nor the glycoprotein from the envelope of this virus protected the mice. It is concluded that SFV-induced immunopotentiation against cancer is not due to covalent linkage of tumour specific transplantation antigen (TSTA) to viral envelope protein but more probably is due to the apposition of viral glycoprotein and cellular TSTA in the plasma membrane of the cancer cell
Combining Charlson and Elixhauser scores with varying lookback predicated mortality better than using individual scores
Objective:
To investigate variation in the presence of secondary diagnosis codes in Charlson and Elixhauser comorbidity scores and assess whether including a 1-year lookback period improved prognostic adjustment by these scores individually, and combined, for 30-day mortality.
Study Design and Setting:
We analyzed inpatient admissions from January 1, 2007 to May 18, 2018 in Oxfordshire, UK. Comorbidity scores were calculated using secondary diagnostic codes in the diagnostic-dominant episode, and primary and secondary codes from the year before. Associations between scores and 30-day mortality were investigated using Cox models with natural cubic splines for nonlinearity, assessing fit using Akaike Information Criteria.
Results:
The 1-year lookback improved model fit for Charlson and Elixhauser scores vs. using diagnostic-dominant methods. Including both, and allowing nonlinearity, improved model fit further. The diagnosis-dominant Charlson score and Elixhauser score using a 1-year lookback, and their interaction, provided the best comorbidity adjustment (reduction in AIC: 761 from best single score model).
Conclusion:
The Charlson and Elixhauser score calculated using primary and secondary diagnostic codes from 1-year lookback with secondary diagnostic codes from the current episode improved individual predictive ability. Ideally, comorbidities should be adjusted for using both the Charlson (diagnostic-dominant) and Elixhauser (1-year lookback) scores, incorporating nonlinearity and interactions for optimal confounding control
Design principles governing the development of theranostic anticancer agents and their nanoformulations with photoacoustic properties
The unmet need to develop novel approaches for cancer diagnosis and treatment has led to the evolution of theranostic agents, which usually include, in addition to the anticancer drug, an imaging agent based mostly on fluorescent agents. Over the past few years, a non-invasive photoacoustic imaging modality has been effectively integrated into theranostic agents. Herein, we shed light on the design principles governing the development of theranostic agents with photoacoustic properties, which can be formulated into nanocarriers to enhance their potency. Specifically, we provide an extensive analysis of their individual constituents including the imaging dyes, drugs, linkers, targeting moieties, and their formulation into nanocarriers. Along these lines, we present numerous relevant paradigms. Finally, we discuss the clinical relevance of the specific strategy, as also the limitations and future perspectives, and through this review, we envisage paving the way for the development of theranostic agents endowed with photoacoustic properties as effective anticancer medicines
Studies on the storage of potatoes II. The temperature conditions inside potato clamps
RESP-297
Studies on the storage of potatoes. III. The composition of the atmosphere in a potato clamp
RESP-297
Short-term genome stability of serial Clostridium difficile ribotype 027 isolates in an experimental gut model and recurrent human disease
Copyright: © 2013 Eyre et al. This 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 creditedClostridium difficile whole genome sequencing has the potential to identify related isolates, even among otherwise indistinguishable strains, but interpretation depends on understanding genomic variation within isolates and individuals.Serial isolates from two scenarios were whole genome sequenced. Firstly, 62 isolates from 29 timepoints from three in vitro gut models, inoculated with a NAP1/027 strain. Secondly, 122 isolates from 44 patients (2–8 samples/patient) with mostly recurrent/on-going symptomatic NAP-1/027 C. difficile infection. Reference-based mapping was used to identify single nucleotide variants (SNVs).Across three gut model inductions, two with antibiotic treatment, total 137 days, only two new SNVs became established. Pre-existing minority SNVs became dominant in two models. Several SNVs were detected, only present in the minority of colonies at one/two timepoints. The median (inter-quartile range) [range] time between patients’ first and last samples was 60 (29.5–118.5) [0–561] days. Within-patient C. difficile evolution was 0.45 SNVs/called genome/year (95%CI 0.00–1.28) and within-host diversity was 0.28 SNVs/called genome (0.05–0.53). 26/28 gut model and patient SNVs were non-synonymous, affecting a range of gene targets.The consistency of whole genome sequencing data from gut model C. difficile isolates, and the high stability of genomic sequences in isolates from patients, supports the use of whole genome sequencing in detailed transmission investigations.Peer reviewe
Evolutionary epidemiology predicts the emergence of glyphosate resistance in a major agricultural weed
The evolution of resistance to herbicides is a striking example of rapid, human-directed adaptation with major consequences for food production. Most studies of herbicide resistance are performed reactively and focus on post-hoc determination of resistance mechanisms following the evolution of field resistance. If the evolution of resistance can be anticipated however, pro-active management to slow or prevent resistance traits evolving can be advocated.
We report a national-scale study that combines population monitoring, glyphosate sensitivity assays, quantitative genetics and epidemiological analyses to pro-actively identify the prerequisites for adaptive evolution (directional selection and heritable genetic variation) to the world’s most widely used herbicide (glyphosate) in a major, economically damaging weed species, Alopecurus myosuroides.
Results highlighted pronounced, heritable variability in glyphosate sensitivity amongst UK A. myosuroides populations. We demonstrated a direct epidemiological link between historical glyphosate selection and current population-level sensitivity, and show that current field populations respond to further glyphosate selection.
This study provides a novel, pro-active assessment of adaptive potential for herbicide resistance, and provides compelling evidence of directional selection for glyphosate insensitivity in advance of reports of field resistance. The epidemiological approach developed can provide a basis for further pro-active study of resistance evolution across pesticide resistance disciplines
Electron-beam propagation in a two-dimensional electron gas
A quantum mechanical model based on a Green's function approach has been used
to calculate the transmission probability of electrons traversing a
two-dimensional electron gas injected and detected via mode-selective quantum
point contacts. Two-dimensional scattering potentials, back-scattering, and
temperature effects were included in order to compare the calculated results
with experimentally observed interference patterns. The results yield detailed
information about the distribution, size, and the energetic height of the
scattering potentials.Comment: 7 pages, 6 figure
Using B isotopes and B/Ca in corals from low saturation springs to constrain calcification mechanisms
Ocean acidification is expected to negatively impact calcifying organisms, yet we lack understanding of their acclimation potential in the natural environment. Here we measured geochemical proxies (δ11B and B/Ca) in Porites astreoides corals that have been growing for their entire life under low aragonite saturation (Ωsw: 0.77–1.85). This allowed us to assess the ability of these corals to manipulate the chemical conditions at the site of calcification (Ωcf), and hence their potential to acclimate to changing Ωsw. We show that lifelong exposure to low Ωsw did not enable the corals to acclimate and reach similar Ωcf as corals grown under ambient conditions. The lower Ωcf at the site of calcification can explain a large proportion of the decreasing P. astreoides calcification rates at low Ωsw. The naturally elevated seawater dissolved inorganic carbon concentration at this study site shed light on how different carbonate chemistry parameters affect calcification conditions in corals
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