551 research outputs found
Cost-benefit analysis of introducing next-generation sequencing (metagenomic) pathogen testing in the setting of pyrexia of unknown origin
Pyrexia of unknown origin (PUO) is defined as a temperature of >38.3°C that lasts for >3 weeks, where no cause can be found despite appropriate investigation. Existing protocols for the work-up of PUO can be extensive and costly, motivating the application of recent advances in molecular diagnostics to pathogen testing. There have been many reports describing various analytical methods and performance of metagenomic pathogen testing in clinical samples but the economics of it has been less well studied. This study pragmatically evaluates the feasibility of introducing metagenomic testing in this setting by assessing the relative cost of clinically-relevant strategies employing this investigative tool under various cost and performance scenarios using Singapore as a demonstration case, and assessing the price and performance benchmarks, which would need to be achieved for metagenomic testing to be potentially considered financially viable relative to the current diagnostic standard. This study has some important limitations: we examined only impact of introducing the metagenomic test to the overall diagnostic cost and excluded costs associated with hospitalization and makes assumptions about the performance of the routine diagnostic tests, limiting the cost of metagenomic test, and the lack of further work-up after positive pathogen detection by the metagenomic test. However, these assumptions were necessary to keep the model within reasonable limits. In spite of these, the simplified presentation lends itself to the illustration of the key insights of our paper. In general, we find the use of metagenomic testing as second-line investigation is effectively dominated, and that use of metagenomic testing at first-line would typically require higher rates of detection or lower cost than currently available in order to be justifiable purely as a cost-saving measure. We conclude that current conditions do not warrant a widespread rush to deploy metagenomic testing to resolve any and all uncertainty, but rather as a front-line technology that should be used in specific contexts, as a supplement to rather than a replacement for careful clinical judgement
Activation of PI3-Kinase Is Required for AMPA Receptor Insertion during LTP of mEPSCs in Cultured Hippocampal Neurons
AbstractHippocampal CA1 homosynaptic long-term potentiation (LTP) is expressed specifically at activated synapses. Increased insertion of postsynaptic α-amino-3-hydroxy-5-methyl-isoxazole-4-propionic acid receptors (AMPARs) appears to be crucial for CA1 LTP. However, the mechanism underlying AMPAR insertion during LTP remains largely unknown. We now report that phosphatidylinositol 3-kinase (PI3K) is complexed with AMPARs at synapses and activated by selective stimulation of synaptic N-methyl-D-aspartate (NMDA) receptors. Activation of the AMPAR-associated PI3K is required for the increased cell surface expression of AMPARs and LTP. Thus, our results strongly suggest that the AMPAR-PI3K complex may constitute a critical molecular signal responsible for AMPAR insertion at activated CA1 synapses during LTP, and consequently, this lipid kinase may serve to determine the polarity of NMDA receptor-dependent synaptic plasticity
Signaling pathway of ginsenoside-Rg1 leading to nitric oxide production in endothelial cells.
We here provide definitive evidence that ginsenoside-Rg1, the pharmacologically active component of ginseng, is a functional ligand of the glucocorticoid receptor (GR) as determined by fluorescence polarization assay. Rg1 increased the phosphorylation of GR, phosphatidylinositol-3 kinase (PI3K), Akt/PKB and endothelial nitric oxide synthase (eNOS) leading to increase nitric oxide (NO) production in human umbilical vein endothelial cell. Rg1-induced eNOS phosphorylation and NO production were significantly reduced by RU486, LY294,002, or SH-6. Also, knockdown of GR completely eliminated the Rg1-induced NO production. This study revealed that Rg1 can indeed serve as an agonist ligand for GR and the activated GR can induce rapid NO production from eNOS via the non-transcriptional PI3K/Akt pathway
Signatures of Relativistic Neutrinos in CMB Anisotropy and Matter Clustering
We present a detailed analytical study of ultra-relativistic neutrinos in
cosmological perturbation theory and of the observable signatures of
inhomogeneities in the cosmic neutrino background. We note that a modification
of perturbation variables that removes all the time derivatives of scalar
gravitational potentials from the dynamical equations simplifies their solution
notably. The used perturbations of particle number per coordinate, not proper,
volume are generally constant on superhorizon scales. In real space an
analytical analysis can be extended beyond fluids to neutrinos.
The faster cosmological expansion due to the neutrino background changes the
acoustic and damping angular scales of the cosmic microwave background (CMB).
But we find that equivalent changes can be produced by varying other standard
parameters, including the primordial helium abundance. The low-l integrated
Sachs-Wolfe effect is also not sensitive to neutrinos. However, the gravity of
neutrino perturbations suppresses the CMB acoustic peaks for the multipoles
with l>~200 while it enhances the amplitude of matter fluctuations on these
scales. In addition, the perturbations of relativistic neutrinos generate a
*unique phase shift* of the CMB acoustic oscillations that for adiabatic
initial conditions cannot be caused by any other standard physics. The origin
of the shift is traced to neutrino free-streaming velocity exceeding the sound
speed of the photon-baryon plasma. We find that from a high resolution, low
noise instrument such as CMBPOL the effective number of light neutrino species
can be determined with an accuracy of sigma(N_nu) = 0.05 to 0.09, depending on
the constraints on the helium abundance.Comment: 38 pages, 7 figures. Version accepted for publication in PR
Efficacy and safety of cumaru syrup as complementary therapy in mild persistent asthma: a double-blind, randomized, placebo-controlled study
Amburana cearensis is a medicinal plant known as "cumaru". It is used in Northeast Brazil in the treatment of respiratory diseases. This was a randomized, double-blind, placebo-controlled study, with the aim of evaluating the efficacy and safety of cumaru syrup as complementary therapy in mild persistent asthma. The study consisted of 3 phases, pre-treatment, treatment and post-treatment. The primary efficacy outcome was comparison of the changes reported by patients of the cumaru and placebo groups after treatment, using the "Asthma Quality of Life Questionnaire" (AQLQ). The secondary outcome was the effect of cumaru syrup on lung function based on spirometry. The results showed that in the cumaru group, the proportion of patients who had global improvement in asthma symptoms was significantly greater (61.90%, P=0.0009) than in the placebo group (9.52%). Only the spirometric parameters Forced Vital Capacity (FVC) and Forced Expiratory Volume in 1 second (FEV1) showed significant intergroup differences in post-treatment (P0.05). Adverse events were reported by 3 patients (14.29%) in the cumaru group and 3 patients (14.29%) in the placebo group. All adverse events were considered non-serious and mild.Amburana cearensis é uma planta medicinal conhecida como "cumaru". No Nordeste do Brasil é usada no tratamento de doenças respiratórias. Este é um estudo randomizado, duplo-cego e controlado por placebo, com o objetivo de avaliar a eficácia e segurança do xarope de cumaru como terapia complementar da asma persistente leve. O estudo consistiu de três fases, pré-tratamento, tratamento e pós-tratamento. A variável primária para determinação da eficácia foi a comparação das mudanças referidas pelos pacientes dos grupos cumaru e placebo após o tratamento, usando o "Questionário sobre Qualidade de Vida na Asma" (QQVA). A variável secundária foi o efeito do xarope de cumaru na função pulmonar baseado na espirometria. Os resultados mostraram que no grupo cumaru, a proporção de pacientes com melhora global dos sintomas da asma foi significativamente maior (61,90%, P=0.0009) que no grupo placebo (9,52%). Somente os parâmetros espirométricos, capacidade vital forçada (CVF) e volume expiratório forçado no primeiro segundo (VEF1), mostraram diferença intergrupo significtivas no pós-tratamento (P0.05). Eventos adversos foram reportados por 3 pacientes (14,29%) no grupo cumaru e 3 (14,29%) no grupo placebo. Todos os eventos adversos foram não sérios e leves
Widespread aberrant alternative splicing despite molecular remission in chronic myeloid leukaemia patients
Vast transcriptomics and epigenomics changes are characteristic of human cancers, including leukaemia. At remission, we assume that these changes normalise so that omics-profiles resemble those of healthy individuals. However, an in-depth transcriptomic and epigenomic analysis of cancer remission has not been undertaken. A striking exemplar of targeted remission induction occurs in chronic myeloid leukaemia (CML) following tyrosine kinase inhibitor (TKI) therapy. Using RNA sequencing and whole-genome bisulfite sequencing, we profiled samples from chronic-phase CML patients at diagnosis and remission and compared these to healthy donors. Remarkably, our analyses revealed that abnormal splicing distinguishes remission samples from normal controls. This phenomenon is independent of the TKI drug used and in striking contrast to the normalisation of gene expression and DNA methylation patterns. Most remarkable are the high intron retention (IR) levels that even exceed those observed in the diagnosis samples. Increased IR affects cell cycle regulators at diagnosis and splicing regulators at remission. We show that aberrant splicing in CML is associated with reduced expression of specific splicing factors, histone modifications and reduced DNA methylation. Our results provide novel insights into the changing transcriptomic and epigenomic landscapes of CML patients during remission. The conceptually unanticipated observation of widespread aberrant alternative splicing after remission induction warrants further exploration. These results have broad implications for studying CML relapse and treating minimal residual disease.Ulf Schmitz, Jaynish S. Shah, Bijay P. Dhungel, Geoffray Monteuuis, Phuc-Loi Luu, Veronika Petrova, Cynthia Metierre, Shalima S. Nair, Charles G. Bailey, Verity A. Saunders, Ali G. Turhan, Deborah L. White, Susan Branford, Susan J. Clark, Timothy P. Hughes, Justin J.-L. Wong, and John E.J. Rask
The Third International Symposium on Fungal Stress – ISFUS
Stress is a normal part of life for fungi, which can survive in environments considered inhospitable or hostile for other organisms. Due to the ability of fungi to respond to, survive in, and transform the environment, even under severe stresses, many researchers are exploring the mechanisms that enable fungi to adapt to stress. The International Symposium on Fungal Stress (ISFUS) brings together leading scientists from around the world who research fungal stress. This article discusses presentations given at the third ISFUS, held in São José dos Campos, São Paulo, Brazil in 2019, thereby summarizing the state-of-the-art knowledge on fungal stress, a field that includes microbiology, agriculture, environmental science, ecology, biotechnology, medicine, and astrobiology
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