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https://www.readbyqxmd.com/read/28335193/facile-synthesis-of-gd-functionalized-gold-nanoclusters-as-potential-mri-ct-contrast-agents
#1
Wenjun Le, Shaobin Cui, Xin Chen, Huanhuan Zhu, Bingdi Chen, Zheng Cui
Multi-modal imaging plays a key role in the earlier detection of disease. In this work, a facile bioinspired method was developed to synthesize Gd-functionalized gold nanoclusters (Gd-Au NCs). The Gd-Au NCs exhibit a uniform size, with an average size of 5.6 nm in dynamic light scattering (DLS), which is a bit bigger than gold clusters (3.74 nm, DLS), while the fluorescent properties of Gd-Au NCs are almost the same as that of Au NCs. Moreover, the Gd-Au NCs exhibit a high longitudinal relaxivity value (r1) of 22...
April 9, 2016: Nanomaterials
https://www.readbyqxmd.com/read/28334271/a-temperature-dependent-phenology-model-for-liriomyza-huidobrensis-diptera-agromyzidae
#2
Norma Mujica, Marc Sporleder, Pablo Carhuapoma, Jürgen Kroschel
Liriomyza huidobrensis (Blanchard) is an economically important and highly polyphagous worldwide pest. To establish a temperature-dependent phenology model, essential for understanding the development and growth of the pest population under a variety of climates and as part of a pest risk analysis, L. huidobrensis life-table data were collected under laboratory conditions at seven constant temperatures on its host faba bean (Vicia faba L.). Several nonlinear equations were fitted to each life stage to model the temperature-dependent population growth and species life history and finally compile an overall temperature-dependent pest phenology model using the Insect Life Cycle Modeling (ILCYM) software...
March 8, 2017: Journal of Economic Entomology
https://www.readbyqxmd.com/read/28334079/how-do-cold-adapted-plants-respond-to-climatic-cycles-interglacial-expansion-explains-current-distribution-and-genomic-diversity-in-primula-farinosa-l
#3
Spyros Theodoridis, Christophe Randin, Peter Szövényi, Florian C Boucher, Theofania S Patsiou, Elena Conti
Understanding the effects of past climatic fluctuations on the distribution and population-size dynamics of cold-adapted species is essential for predicting their responses to ongoing global climate change. In spite of the heterogeneity of cold-adapted species, two main contrasting hypotheses have been proposed to explain their responses to Late Quaternary glacial cycles, namely, the interglacial contraction versus the interglacial expansion hypotheses. Here, we use the cold-adapted plant Primula farinosa to test two demographic models under each of the two alternative hypotheses and a fifth, null model...
December 21, 2016: Systematic Biology
https://www.readbyqxmd.com/read/28334037/ang1-treatment-reduces-muscle-pathology-and-prevents-a-decline-in-perfusion-in-dmd-mice
#4
Kelly M Gutpell, Nikola Tasevski, Boaz Wong, William Thomas Hrinivich, Feng Su, Jennifer Hadway, Lise Desjardins, Ting-Yim Lee, Lisa Marie Hoffman
Vascular endothelial growth factor (VEGF) and other pro-angiogenic growth factors have been investigated to enhance muscle tissue perfusion and repair in Duchenne muscular dystrophy (DMD). Current understanding is limited by a lack of functional data following in vivo delivery of these growth factors. We previously used dynamic contrast-enhanced computed tomography to monitor disease progression in murine models of DMD, but no study to date has utilized this imaging technique to assess vascular therapy in a preclinical model of DMD...
2017: PloS One
https://www.readbyqxmd.com/read/28333893/magnetic-resonance-imaging-characteristics-of-a-baerveldt-glaucoma-implant
#5
Daniel M Anderson, Ryan B Schwope, Michael J Reiter, Abraham W Suhr
PURPOSE: Evaluate for normative postoperative magnetic resonance imaging (MRI) characteristics of a Baerveldt Glaucoma Implant (BGI). DESIGN: Prospective case series. PARTICIPANTS: Seven subjects with uncontrolled glaucoma requiring a primary superotemporal BGI. METHODS: Subjects prospectively underwent sequential MRI orbital scans without contrast at 0 to 2 weeks, 6 to 8 weeks, and 4 to 6 months after implantation of a BGI model 103-250...
March 22, 2017: Journal of Glaucoma
https://www.readbyqxmd.com/read/28333590/mean-first-passage-memory-lifetimes-by-reducing-complex-synapses-to-simple-synapses
#6
Terry Elliott
Memory models that store new memories by forgetting old ones have memory lifetimes that are rather short and grow only logarithmically in the number of synapses. Attempts to overcome these deficits include "complex" models of synaptic plasticity in which synapses possess internal states governing the expression of synaptic plasticity. Integrate-and-express, filter-based models of synaptic plasticity propose that synapses act as low-pass filters, integrating plasticity induction signals before expressing synaptic plasticity...
March 23, 2017: Neural Computation
https://www.readbyqxmd.com/read/28333248/the-evolutionary-dynamics-of-orthologs-that-shift-in-gene-body-methylation-between-arabidopsis-species
#7
Shohei Takuno, Danelle K Seymour, Brandon S Gaut
DNA methylation labels a specific subset of genes in plant genomes. Recent work has shown that this gene-body methylation (gbM) is a conserved feature of orthologs, because highly methylated genes in one species tend to be highly methylated in another. In this study, we examined the exceptions to that rule by identifying genes that differ in gbM status between two plant species - Arabidopsis thaliana and Arabidopsis lyrata. Using Capsella grandiflora as an outgroup, we polarized the loss and gain of gbM for orthologs in Arabidopsis lineages...
March 2, 2017: Molecular Biology and Evolution
https://www.readbyqxmd.com/read/28333164/the-theory-of-parallel-climate-realizations-as-a-new-framework-for-teleconnection-analysis
#8
Mátyás Herein, Gábor Drótos, Tímea Haszpra, János Márfy, Tamás Tél
Teleconnections are striking features of the Earth climate system which appear as statistically correlated climate-related patterns between remote geographical regions of the globe. In a changing climate, however, the strength of teleconnections might change, and an appropriate characterization of these correlations and their change (more appropriate than detrending the time series) is lacking in the literature. Here we present a novel approach, based on the theory of snapshot attractors, corresponding in our context to studying parallel climate realizations...
March 23, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28332980/a-receptor-and-neuron-that-activate-a-circuit-limiting-sucrose-consumption
#9
Ryan M Joseph, Jennifer S Sun, Edric Tam, John R Carlson
The neural control of sugar consumption is critical for normal metabolism. In contrast to sugar-sensing taste neurons that promote consumption, we identify a taste neuron that limits sucrose consumption in Drosophila. Silencing of the neuron increases sucrose feeding; optogenetic activation decreases it. The feeding inhibition depends on the IR60b receptor, as shown by behavioral analysis and Ca2+ imaging of an IR60b mutant. The IR60b phenotype shows a high degree of chemical specificity when tested with a broad panel of tastants...
March 23, 2017: ELife
https://www.readbyqxmd.com/read/28331741/pet-mri-findings-of-two-patients-with-breast-carcinoma-before-treatment
#10
Filiz Çelebi, Ülkühan Köksal, Kezban Nur Pilancı, Çetin Ordu, Dauren Sarsenov, Serkan İlgün, Fatmagül Kuşku Çabuk, Gül Alço, Güzide Özdil, Zeynep Erdoğan, Vahit Özmen
Integrated positron-emission tomography-magnetic resonance imaging (PET-MRI) is a new hybrid simultaneous imaging modality with higher soft tissue contrast and lower radiation doses compared with PET-CT. Two patients who were referred to our hospital with left breast masses that were pathologically diagnosed as invasive ductal carcinoma. The women were then scanned using the first PET-MRI system in Turkey, which was established in our department. In this case report, we aimed to determine the advantages of PET-MRI in staging, follow-up, neoadjuvant chemotherapy response, and to compare the usefulness of this modality with PET-CT and dynamic contrast-enhanced breast MRI...
April 2016: J Breast Health (2013)
https://www.readbyqxmd.com/read/28331597/pollinator-population-size-and-pollination-ecosystem-service-responses-to-enhancing-floral-and-nesting-resources
#11
Johanna Häussler, Ullrika Sahlin, Charlotte Baey, Henrik G Smith, Yann Clough
Modeling pollination ecosystem services requires a spatially explicit, process-based approach because they depend on both the behavioral responses of pollinators to the amount and spatial arrangement of habitat and on the within- and between-season dynamics of pollinator populations in response to land use. We describe a novel pollinator model predicting flower visitation rates by wild central-place foragers (e.g., nesting bees) in spatially explicit landscapes. The model goes beyond existing approaches by: (1) integrating preferential use of more rewarding floral and nesting resources; (2) considering population growth over time; (3) allowing different dispersal distances for workers and reproductives; (4) providing visitation rates for use in crop pollination models...
March 2017: Ecology and Evolution
https://www.readbyqxmd.com/read/28330878/linear-summation-of-repulsive-and-attractive-serial-dependencies-orientation-and-motion-dependencies-sum-in-motion-perception
#12
David Alais, Johahn Leung, Erik Van der Burg
Recent work from several groups has shown that perception of various visual attributes in human observers at a given moment is biased towards what was recently seen. This positive serial dependency is a kind of temporal averaging which exploits short-term correlations in visual scenes to reduce noise and stabilise perception. To date this stabilising 'continuity field' has been demonstrated on stable visual attributes such as orientation and face identity, yet it would be counterproductive to apply it to dynamic attributes where change sensitivity is needed...
March 22, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/28330616/systematic-analysis-of-human-protein-phosphatase-interactions-and-dynamics
#13
Leena Yadav, Fitsum Tamene, Helka Göös, Audrey van Drogen, Riku Katainen, Ruedi Aebersold, Matthias Gstaiger, Markku Varjosalo
Coordinated activities of protein kinases and phosphatases ensure phosphorylation homeostasis, which, when perturbed, can instigate diseases, including cancer. Yet, in contrast to kinases, much less is known about protein phosphatase functions and their interactions and complexes. Here, we used quantitative affinity proteomics to assay protein-protein interactions for 54 phosphatases distributed across the three major protein phosphatase families, with additional analysis of their 12 co-factors. We identified 838 high-confidence interactions, of which 631, to our knowledge, have not been reported before...
March 15, 2017: Cell Systems
https://www.readbyqxmd.com/read/28330464/spectral-temporal-eeg-dynamics-of-speech-discrimination-processing-in-infants-during-sleep
#14
Phillip M Gilley, Kristin Uhler, Kaylee Watson, Christine Yoshinaga-Itano
BACKGROUND: Oddball paradigms are frequently used to study auditory discrimination by comparing event-related potential (ERP) responses from a standard, high probability sound and to a deviant, low probability sound. Previous research has established that such paradigms, such as the mismatch response or mismatch negativity, are useful for examining auditory processes in young children and infants across various sleep and attention states. The extent to which oddball ERP responses may reflect subtle discrimination effects, such as speech discrimination, is largely unknown, especially in infants that have not yet acquired speech and language...
March 22, 2017: BMC Neuroscience
https://www.readbyqxmd.com/read/28330415/novel-detection-of-placental-insufficiency-by-magnetic-resonance-imaging-in-the-nonhuman-primate
#15
Jamie O Lo, Victoria H J Roberts, Matthias C Schabel, Xiaojie Wang, Terry K Morgan, Zheng Liu, Colin Studholme, Christopher D Kroenke, Antonio E Frias
The placenta is a vital organ necessary for healthy fetal development. Placental insufficiency creates an in utero environment where the fetus is at risk of insufficient oxygen or nutrient exchange. This is primarily caused by impairment of either maternal or fetal circulation or vascular thrombosis such as placental infarction. As a result of placental dysfunction, affected fetuses may be growth restricted, neurologically impaired, and at risk of increased morbidity and mortality. In a cohort of 4 pregnant Rhesus macaques, we describe antenatal detection of naturally occurring intrauterine growth restriction (IUGR) and aberrant fetal neurodevelopment in 1 animal...
January 1, 2017: Reproductive Sciences
https://www.readbyqxmd.com/read/28326779/illuminating-photochemistry-of-an-excitation-ratiometric-fluorescent-protein-calcium-biosensor
#16
Longteng Tang, Yanli Wang, Weimin Liu, Yongxin Zhao, Robert E Campbell, Chong Fang
Fluorescent protein (FP) based biosensors have become an important and promising tool to track metal ion movement inside living systems. Their working principles after light irradiation, however, remain elusive. To facilitate the rational design of biosensors, we dissect the fluorescence modulation mechanism of a newly developed excitation ratiometric green FP-based Ca(2+) biosensor, GEX-GECO1, using femtosecond stimulated Raman spectroscopy (FSRS) in the electronic excited state. Upon 400 nm photoexcitation, characteristic vibrational marker bands at ~1180 and 1300 cm(-1) show concomitant decay and rise dynamics, probing the progression of an ultrafast excited state proton transfer (ESPT) reaction...
March 22, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28326040/effects-of-topical-icing-on-inflammation-angiogenesis-revascularization-and-myofiber-regeneration-in-skeletal-muscle-following-contusion-injury
#17
Daniel P Singh, Zohreh Barani Lonbani, Maria A Woodruff, Tony J Parker, Roland Steck, Jonathan M Peake
Contusion injuries in skeletal muscle commonly occur in contact sport and vehicular and industrial workplace accidents. Icing has traditionally been used to treat such injuries under the premise that it alleviates pain, reduces tissue metabolism, and modifies vascular responses to decrease swelling. Previous research has examined the effects of icing on inflammation and microcirculatory dynamics following muscle injury. However, whether icing influences angiogenesis, collateral vessel growth, or myofiber regeneration remains unknown...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/28325942/comparative-genomics-reveals-contraction-in-olfactory-receptor-genes-in-bats
#18
Georgia Tsagkogeorga, Steven Müller, Christophe Dessimoz, Stephen J Rossiter
Gene loss and gain during genome evolution are thought to play important roles in adaptive phenotypic diversification. Among mammals, bats possess the smallest genomes and have evolved the unique abilities of powered flight and laryngeal echolocation. To investigate whether gene family evolution has contributed to the genome downsizing and phenotypic diversification in this group, we performed comparative evolutionary analyses of complete proteome data for eight bat species, including echolocating and non-echolocating forms, together with the proteomes of 12 other laurasiatherian mammals...
March 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28325911/theoretical-and-computational-validation-of-the-kuhn-barrier-friction-mechanism-in-unfolded-proteins
#19
Stanislav M Avdoshenko, Atanu Das, Rohit Satija, Garegin A Papoian, Dmitrii E Makarov
A long time ago, Kuhn predicted that long polymers should approach a limit where their global motion is controlled by solvent friction alone, with ruggedness of their energy landscapes having no consequences for their dynamics. In contrast, internal friction effects are important for polymers of modest length. Internal friction in proteins, in particular, affects how fast they fold or find their binding targets and, as such, has attracted much recent attention. Here we explore the molecular origins of internal friction in unfolded proteins using atomistic simulations, coarse-grained models and analytic theory...
March 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28325514/multiparametric-approach-with-diffusion-weighted-imaging-and-dynamic-contrast-enhanced-mri-a-comparison-study-for-differentiating-between-benign-and-malignant-bone-lesions-in-adults
#20
E Oh, Y C Yoon, J H Kim, K Kim
AIM: To evaluate and compare the diagnostic performance of quantitative parameters derived from diffusion-weighted imaging (DWI) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in differentiating benign and malignant bone tumours. MATERIALS AND METHODS: Fifty-five patients (age range, 21-82 years; mean age, 55 years) underwent pretreatment MRI. Apparent diffusion coefficient (ADC) values were calculated by DWI. The DCE-MRI data were analysed for the volume transfer constant (K(trans)), extravascular extracellular volume fraction (Ve), and volume rate constant (Kep), and K(trans)/ADC ratio...
March 18, 2017: Clinical Radiology
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