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https://www.readbyqxmd.com/read/28545207/quality-and-reactivity-of-dissolved-organic-matter-in-a-mediterranean-river-across-hydrological-and-spatial-gradients
#1
Elisabet Ejarque, Anna Freixa, Eusebi Vazquez, Alba Guarch, Stefano Amalfitano, Stefano Fazi, Anna M Romaní, Andrea Butturini
Understanding DOM transport and reactivity in rivers is essential to having a complete picture of the global carbon cycle. In this study, we explore the effects of hydrological variability and downstream transport on dissolved organic matter (DOM) dynamics in a Mediterranean river. We sampled the main stem of the river Tordera from the source to the sea, over a range of fifteen hydrological conditions including extreme events (flood and drought). By exploring spatial and temporal gradients of DOM fluorescence properties, river hydrology was found to be a significant predictor of DOM spatial heterogeneity...
May 20, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28544159/simultaneous-measurement-of-t1-b1-and-pharmacokinetic-model-parameters-using-active-contrast-encoding-ace-mri
#2
Jin Zhang, Kerryanne Winters, Olivier Reynaud, Sungheon Gene Kim
The aim of this study was to assess the feasibility of combining dynamic contrast enhanced-magnetic resonance imaging (DCE-MRI) with the measurement of the radiofrequency (RF) transmit field B1 and pre-contrast longitudinal relaxation time T10 . A novel approach has been proposed to simultaneously estimate B1 and T10 from a modified DCE-MRI scan that actively encodes the washout phase of the curve with different amounts of T1 and B1 weighting using multiple flip angles and repetition times, hence referred to as active contrast encoding (ACE)-MRI...
May 22, 2017: NMR in Biomedicine
https://www.readbyqxmd.com/read/28543921/correlations-of-low-field-nmr-and-variable-field-nmr-parameters-with-osteoarthritis-in-human-articular-cartilage-under-load
#3
Erik Rössler, Carlos Mattea, Simo Saarakkala, Petri Lehenkari, Mikko Finnilä, Lassi Rieppo, Sakari Karhula, Miika T Nieminen, Siegfried Stapf
NMR experiments carried out at magnetic fields below 1 T provide new relaxation parameters unavailable with conventional clinical scanners. Contrast of T1 generally becomes larger towards low fields, as slow molecular reorientation processes dominate relaxation at the corresponding Larmor frequencies. This advantage has to be considered in the context of lower sensitivity and frequently reduced spatial resolution. The layered structure of cartilage is one example where a particularly strong variation of T1 across the tissue occurs, being affected by degenerative diseases such as osteoarthritis (OA)...
May 24, 2017: NMR in Biomedicine
https://www.readbyqxmd.com/read/28543885/dce-mri-prediction-of-survival-time-for-patients-with-glioblastoma-multiforme-using-an-adaptive-neuro-fuzzy-based-model-and-nested-model-selection-technique
#4
Azimeh N V Dehkordi, Alireza Kamali-Asl, Ning Wen, Tom Mikkelsen, Indrin J Chetty, Hassan Bagher-Ebadian
This pilot study investigates the construction of an Adaptive Neuro-Fuzzy Inference System (ANFIS) for the prediction of the survival time of patients with glioblastoma multiforme (GBM). ANFIS is trained by the pharmacokinetic (PK) parameters estimated by the model selection (MS) technique in dynamic contrast enhanced-magnetic resonance imaging (DCE-MRI) data analysis, and patient age. DCE-MRI investigations of 33 treatment-naïve patients with GBM were studied. Using the modified Tofts model and MS technique, the following physiologically nested models were constructed: Model 1, no vascular leakage (normal tissue); Model 2, leakage without efflux; Model 3, leakage with bidirectional exchange (influx and efflux)...
May 25, 2017: NMR in Biomedicine
https://www.readbyqxmd.com/read/28543598/assessment-of-fallopian-tube-fimbria-patency-with-4-dimensional-hysterosalpingo-contrast-sonography-in-infertile-women
#5
Weiqun Wang, Qiulan Zhou, Yafei Gong, Ying Li, Yinying Huang, Zhiyi Chen
OBJECTIVES: The purpose of this study was to evaluate the performance of 4-dimensional (4D) hysterosalpingo-contrast sonography (HyCoSy) for assessing fallopian tube fimbria patency in infertile women. METHODS: Seventy-seven infertile female patients with obstruction at the tubal fimbria or partial obstruction with pelvic adhesions were included. All of the patients underwent 4D HyCoSy enhanced by dynamic observation after a flush of normal saline and were followed with laparoscopic chromopertubation using methylene blue within 6 months...
May 24, 2017: Journal of Ultrasound in Medicine: Official Journal of the American Institute of Ultrasound in Medicine
https://www.readbyqxmd.com/read/28543398/interdigital-tissue-remodelling-in-the-embryonic-limb-involves-dynamic-regulation-of-the-mirna-profiles
#6
Beatriz Garcia-Riart, Carlos I Lorda-Diez, Jessica C Marin-Llera, Juan A Garcia-Porrero, Juan M Hurle, Juan A Montero
Next-generation sequencing in combination with quantitative polymerase chain reaction analysis revealed a dynamic miRNA signature in the interdigital mesoderm of the chick embryonic hinlimb in the course of interdigit remodelling. During this period, 612 previously known chicken miRNAs (gga-miRNAs) and 401 non-identified sequences were expressed in the interdigital mesoderm. Thirty-six microRNAs, represented by more than 750 reads per million, displayed differential expression between stages HH29 (6 id) and HH32 (7...
May 24, 2017: Journal of Anatomy
https://www.readbyqxmd.com/read/28543071/differentiating-enhancing-multiple-sclerosis-lesions-glioblastoma-and-lymphoma-with-dynamic-texture-parameters-analysis-dtpa-a-feasibility-study
#7
Rajeev K Verma, Roland Wiest, C Locher, Mirjam R Heldner, Phillip Schucht, Andreas Raabe, Jan Gralla, Christian Philipp Kamm, Johannes Slotboom, Frauke Kellner-Weldon
PURPOSE: MR-imaging hallmarks of glioblastoma (GB), cerebral lymphoma (CL), and demyelinating lesions are gadolinium (Gd) uptake due to blood brain barrier disruption. Thus, initial diagnosis may be difficult based on conventional Gd enhanced MRI alone. Here, the added value of a dynamic texture parameter analysis (DTPA) in the differentiation between these three entities is examined. DTPA is an in-house software tool that incorporates the analysis of quantitative texture parameters extracted from dynamic susceptibility contrast enhanced (DSCE) images...
May 19, 2017: Medical Physics
https://www.readbyqxmd.com/read/28543030/defining-epileptogenic-networks-contribution-of-seeg-and-signal-analysis
#8
REVIEW
Fabrice Bartolomei, Stanislas Lagarde, Fabrice Wendling, Aileen McGonigal, Viktor Jirsa, Maxime Guye, Christian Bénar
Epileptogenic networks are defined by the brain regions involved in the production and propagation of epileptic activities. In this review we describe the historical, methodologic, and conceptual bases of this model in the analysis of electrophysiologic intracerebral recordings. In the context of epilepsy surgery, the determination of cerebral regions producing seizures (i.e., the "epileptogenic zone") is a crucial objective. In contrast with a traditional focal vision of focal drug-resistant epilepsies, the concept of epileptogenic networks has been progressively introduced as a model better able to describe the complexity of seizure dynamics and realistically describe the distribution of epileptogenic anomalies in the brain...
May 20, 2017: Epilepsia
https://www.readbyqxmd.com/read/28542622/meta-analysis-of-magnetic-resonance-imaging-accuracy-for-diagnosis-of-oral-cancer
#9
Marcelo Aldrighi Moreira, Luiza Silveira Lessa, Francieli Regina Bortoli, Abigail Lopes, Eduardo Picolo Xavier, Renan Antonio Ceretta, Fernanda Guglielmi Faustini Sônego, Cristiane Damiani Tomasi, Patricia Duarte Simões Pires, Luciane Bisognin Ceretta, Ingrid Dalira Schweigert Perry, Priscyla Waleska Simões
OBJECTIVE: To establish the diagnostic accuracy of magnetic resonance imaging (MRI) as an auxiliary means for the diagnosis of oral cancer through a systematic review and meta-analysis. METHODS: An exhaustive search of publications from 1986 to 2016 was performed of Medline, Embase and Cochrane (and related databases), including grey literature. Primary diagnostic accuracy studies that assessed oral cancer (target condition) using MRI (index test) were included...
2017: PloS One
https://www.readbyqxmd.com/read/28542603/a-conformational-switch-high-throughput-screening-assay-and-allosteric-inhibition-of-the-flavivirus-ns2b-ns3-protease
#10
Matthew Brecher, Zhong Li, Binbin Liu, Jing Zhang, Cheri A Koetzner, Adham Alifarag, Susan A Jones, Qishan Lin, Laura D Kramer, Hongmin Li
The flavivirus genome encodes a single polyprotein precursor requiring multiple cleavages by host and viral proteases in order to produce the individual proteins that constitute an infectious virion. Previous studies have revealed that the NS2B cofactor of the viral NS2B-NS3 heterocomplex protease displays a conformational dynamic between active and inactive states. Here, we developed a conformational switch assay based on split luciferase complementation (SLC) to monitor the conformational change of NS2B and to characterize candidate allosteric inhibitors...
May 25, 2017: PLoS Pathogens
https://www.readbyqxmd.com/read/28542553/quantitative-mri-for-analysis-of-peritumoral-edema-in-malignant-gliomas
#11
Ida Blystad, J B Marcel Warntjes, Örjan Smedby, Peter Lundberg, Elna-Marie Larsson, Anders Tisell
BACKGROUND AND PURPOSE: Damage to the blood-brain barrier with subsequent contrast enhancement is a hallmark of glioblastoma. Non-enhancing tumor invasion into the peritumoral edema is, however, not usually visible on conventional magnetic resonance imaging. New quantitative techniques using relaxometry offer additional information about tissue properties. The aim of this study was to evaluate longitudinal relaxation R1, transverse relaxation R2, and proton density in the peritumoral edema in a group of patients with malignant glioma before surgery to assess whether relaxometry can detect changes not visible on conventional images...
2017: PloS One
https://www.readbyqxmd.com/read/28542493/the-in-vivo-structure-of-biological-membranes-and-evidence-for-lipid-domains
#12
Jonathan D Nickels, Sneha Chatterjee, Christopher B Stanley, Shuo Qian, Xiaolin Cheng, Dean A A Myles, Robert F Standaert, James G Elkins, John Katsaras
Examining the fundamental structure and processes of living cells at the nanoscale poses a unique analytical challenge, as cells are dynamic, chemically diverse, and fragile. A case in point is the cell membrane, which is too small to be seen directly with optical microscopy and provides little observational contrast for other methods. As a consequence, nanoscale characterization of the membrane has been performed ex vivo or in the presence of exogenous labels used to enhance contrast and impart specificity...
May 2017: PLoS Biology
https://www.readbyqxmd.com/read/28542439/host-mediated-inflammatory-influence-on-glioblastoma-multiforme-recurrence-following-high-dose-ionizing-radiation
#13
J Tyson McDonald, Xuefeng Gao, Cole Steber, Jawon Lee Breed, Caitlin Pollock, Lili Ma, Lynn Hlatky
Despite optimal clinical treatment, glioblastoma multiforme (GBM) inevitably recurs. Standard treatment of GBM, exposes patients to radiation which kills tumor cells, but also modulates the molecular fingerprint of any surviving tumor cells and the cross-talk between those cells and the host. Considerable investigation of short-term (hours to days) post-irradiation tumor cell response has been undertaken, yet long-term responses (weeks to months) which are potentially even more informative of recurrence, have been largely overlooked...
2017: PloS One
https://www.readbyqxmd.com/read/28542408/mocap-proteins-regulated-by-moark1-mediated-phosphorylation-coordinate-endocytosis-and-actin-dynamics-to-govern-development-and-virulence-of-magnaporthe-oryzae
#14
Lianwei Li, Xiaolin Chen, Shengpei Zhang, Jun Yang, Deng Chen, Muxing Liu, Haifeng Zhang, Xiaobo Zheng, Ping Wang, Youliang Peng, Zhengguang Zhang
Actin organization is a conserved cellular process that regulates the growth and development of eukaryotic cells. It also governs the virulence process of pathogenic fungi, such as the rice blast fungus Magnaporthe oryzae, with mechanisms not yet fully understood. In a previous study, we found that actin-regulating kinase MoArk1 displays conserved functions important in endocytosis and actin organization, and MoArk1 is required for maintaining the growth and full virulence of M. oryzae. To understand how MoArk1 might function, we identified capping protein homologs from M...
May 25, 2017: PLoS Genetics
https://www.readbyqxmd.com/read/28542212/proteome-dynamics-of-cold-acclimating-rhododendron-species-contrasting-in-their-freezing-tolerance-and-thermonasty-behavior
#15
Jose V Die, Rajeev Arora, Lisa J Rowland
To gain a better understanding of cold acclimation in rhododendron and in woody perennials in general, we used the 2D-DIGE technique to analyze the rhododendron proteome during the seasonal development of freezing tolerance. We selected two species varying in their cold acclimation ability as well as their thermonasty response (folding of leaves in response to low temperature). Proteins were extracted from leaves of non-acclimated (NA) and cold acclimated (CA) plants of the hardier thermonastic species, R. catawbiense (Cata...
2017: PloS One
https://www.readbyqxmd.com/read/28541675/prediction-of-bond-vector-autocorrelation-functions-from-larmor-frequency-selective-order-parameter-analysis-of-nmr-relaxation-data
#16
Janet S Anderson, Griselda Hernandez, David M LeMaster
Protein molecular dynamics interpretation of the standard R1, R2 and heteronuclear NOE relaxation measurements has typically been limited to a single S(2) order parameter which is often insufficient to characterize the rich content of these NMR experiments. In the absence of exchange linebroadening, an optimized reduced spectral density analysis of these measurements can yield spectral density values at three distinct frequencies. Surprisingly, these three discrete spectral density values have proven to be sufficient for a Larmor frequency-selective order parameter analysis of the 223 methine and methylene H-C bonds of the B3 domain of Protein G (GB3) to accurately back-calculate the entire curve of the corresponding bond vector autocorrelation functions upon which the NMR relaxation behavior depends...
May 25, 2017: Journal of Chemical Theory and Computation
https://www.readbyqxmd.com/read/28541284/a-scalable-double-barcode-sequencing-platform-for-characterization-of-dynamic-protein-protein-interactions
#17
Ulrich Schlecht, Zhimin Liu, Jamie R Blundell, Robert P St Onge, Sasha F Levy
Several large-scale efforts have systematically catalogued protein-protein interactions (PPIs) of a cell in a single environment. However, little is known about how the protein interactome changes across environmental perturbations. Current technologies, which assay one PPI at a time, are too low throughput to make it practical to study protein interactome dynamics. Here, we develop a highly parallel protein-protein interaction sequencing (PPiSeq) platform that uses a novel double barcoding system in conjunction with the dihydrofolate reductase protein-fragment complementation assay in Saccharomyces cerevisiae...
May 25, 2017: Nature Communications
https://www.readbyqxmd.com/read/28540825/the-role-of-t1-perfusion-based-classification-in-predicting-the-outcome-of-magnetic-resonance-guided-high-intensity-focused-ultrasound-treatment-of-adenomyosis
#18
Bilgin Keserci, Nguyen Minh Duc
OBJECTIVE: To assess the relationship between magnetic resonance (MR) T1 perfusion-based classification and the outcome of MR-guided high intensity focused ultrasound treatment of adenomyosis, defined as nonperfused volume (NPV) ratio. METHODS: The adenomyosis of 31 women was classified into group A (time-signal intensity [SI] curve of adenomyosis lower than that of the myometrium) and group B (time-SI curve of adenomyosis equal to or higher than that of the myometrium) on the basis of time-SI curves on dynamic contrast enhanced (DCE) MR images acquired at screening...
May 19, 2017: International Journal of Hyperthermia
https://www.readbyqxmd.com/read/28540727/noiseless-performance-of-prussian-blue-based-bio-sensors-through-power-generation
#19
Maria A Komkova, Elena E Karyakina, Arkady A Karyakin
In contrast to 'self-powered' (bio)sensors aiming to generate maximum energy output, we propose the systems with the lowest potential difference between the working and the counter electrodes, which in galvanic mode would provide achievement of the best analytical performance characteristics. Prussian Blue based (bio)sensors known to operate at 0.00 V versus Ag|AgCl reference, in short-circuit regime generate the current proportional to analyte concentration. Sensitivity and dynamic range of Prussian Blue based (bio)sensors in power generation mode are, respectively, even slightly higher and wider compared to the same (bio)sensors operated in the conventional three-electrode regime powered by a potentiostat...
May 25, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28540212/infarct-characterization-using-ct
#20
REVIEW
Ludovico La Grutta, Patrizia Toia, Erica Maffei, Filippo Cademartiri, Roberto Lagalla, Massimo Midiri
Myocardial infarction (MI) is a major cause of death and disability worldwide. The incidence is not expected to diminish, despite better prevention, diagnosis and treatment, because of the ageing population in industrialized countries and unhealthy lifestyles in developing countries. Nowadays it is highly requested an imaging tool able to evaluate MI and viability. Technology improvements determined an expansion of clinical indications from coronary plaque evaluation to functional applications (perfusion, ischemia and viability after MI) integrating additional phases and information in the mainstream examination...
April 2017: Cardiovascular Diagnosis and Therapy
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