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https://www.readbyqxmd.com/read/28806773/quantitative-accuracy-of-177lu-spect-imaging-for-molecular-radiotherapy
#1
Emilio Mezzenga, Vincenzo D'Errico, Marco D'Arienzo, Lidia Strigari, Koutla Panagiota, Federica Matteucci, Stefano Severi, Giovanni Paganelli, Andrew Fenwick, David Bianchini, Francesco Marcocci, Anna Sarnelli
The purpose of this study is to investigate the optimal reference geometry for gamma camera calibration. Yet another question of interest was to assess the influence of the number of 3D Ordered Subsets Expectation Maximization (3D-OSEM) updates on activity quantification for SPECT imaging with 177Lu. The accuracy of 177Lu activity quantification was assessed both in small and in large objects. Two different reference geometries, namely a cylindrical homogeneous phantom and a Jaszczak 16 ml sphere surrounded by cold water, were used to determine the gamma camera calibration factor of a commercial SPECT/CT system...
2017: PloS One
https://www.readbyqxmd.com/read/28806597/a-nested-multivariate-chemometrics-based-calibration-strategy-for-direct-trace-biometal-analysis-in-soft-tissue-utilizing-energy-dispersive-x-ray-fluorescence-edxrf-and-scattering-spectrometry
#2
REVIEW
J J Okonda, K H Angeyo, J M Mangala, S M Kisia
Compton scatter-modulated fluorescence and multivariate chemometric (artificial neural network (ANN) and principal component regression (PCR)) calibration strategy was explored for direct rapid trace biometals (Mn, Fe, Cu, Zn, Se) analysis in "complex" matrices (model soft tissues). This involved spectral feature selection (multiple fluorescence signatures) normalized to or in conjunction with Compton scatter. ANN model resulted in more accurate trace biometal determination (R(2)>0.9) compared to PCR. Hybrid nested (ANN and PCR) approach led to optimized accurate biometals' concentrations in Oyster tissue (≤ ± 10%)...
August 8, 2017: Applied Radiation and Isotopes
https://www.readbyqxmd.com/read/28806080/dissociative-photoionization-of-the-elusive-vinoxy-radical
#3
Jonathan D Adams, Preston G Scrape, Shih-Huang Lee, Laurie J Butler
These experiments report the dissociative photoionization of vinoxy radicals to m/z = 15 and 29. In a crossed laser-molecular beam scattering apparatus, we induce C-Cl bond fission in 2-chloroacetaldehyde by photoexcitation at 157 nm. Our velocity measurements, combined with conservation of angular momentum, show that 21% of the C-Cl photofission events form vinoxy radicals that are stable to subsequent dissociation to CH3 + CO or H + ketene. Photoionization of these stable vinoxy radicals, identified by their velocities, which are momentum-matched with the higher-kinetic-energy Cl atom photofragments, shows that the vinoxy radicals dissociatively photoionize to give signal at m/z = 15 and 29...
August 14, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/28805868/a-microfluidic-flow-cytometer-enabling-absolute-quantification-of-single-cell-intracellular-proteins
#4
Xiufeng Li, Beiyuan Fan, Shanshan Cao, Deyong Chen, Xiaoting Zhao, Dong Men, Wentao Yue, Junbo Wang, Jian Chen
Quantification of single-cell proteomics provides key insights into cellular heterogeneity while conventional flow cytometry cannot provide absolute quantification of intracellular proteins of single cells due to the lack of calibration approaches. This paper presents a constriction channel (with a cross sectional area smaller than cells) based microfluidic flow cytometer, capable of collecting copy numbers of specific intracellular proteins. In this platform, single cells stained with fluorescence labelled antibodies were forced to squeeze through the constriction channel with the fluorescence intensities quantified and since cells fully filled the constriction channel during the squeezing process, solutions with fluorescence labelled antibodies were flushed into the constriction channel to obtain calibration curves...
August 14, 2017: Lab on a Chip
https://www.readbyqxmd.com/read/28805443/the-effect-of-the-proportion-of-mismatching-trials-and-task-orientation-on-the-confidence-accuracy-relationship-in-unfamiliar-face-matching
#5
Rachel G Stephens, Carolyn Semmler, James D Sauer
Unfamiliar, one-to-one face matching has been shown to be error-prone. However, it is unknown whether there is a strong relationship between confidence and accuracy in this task. If there is, then confidence could be used as an indicator of accuracy in real-world face matching settings such as border security, where the objectively correct decision is typically unknown. Two experiments examined the overall confidence-accuracy relationship, as well as the relationship for positive (match) and negative (mismatch) decisions...
August 14, 2017: Journal of Experimental Psychology. Applied
https://www.readbyqxmd.com/read/28805279/extreme-weather-year-sequences-have-non-additive-effects-on-environmental-nitrogen-losses
#6
Javed Iqbal, Magdalena Necpalova, Sotirios V Archontoulis, Robert P Anex, Marie Bourguignon, Daryl Herzmann, David C Mitchell, John E Sawyer, Qing Zhu, Michael J Castellano
The frequency and intensity of extreme weather years, characterized by abnormal precipitation and temperature, are increasing. In isolation, these years have disproportionately large effects on environmental N losses. However, the sequence of extreme weather years (e.g., wet-dry vs. dry-wet) may affect cumulative N losses. We calibrated and validated the DAYCENT ecosystem process model with a comprehensive set of biogeophysical measurements from a corn-soybean rotation managed at three N fertilizer inputs with and without a winter cover crop in Iowa, USA...
August 14, 2017: Global Change Biology
https://www.readbyqxmd.com/read/28804989/improving-predictions-of-tropical-forest-response-to-climate-change-through-integration-of-field-studies-and-ecosystem-modeling
#7
Xiaohui Feng, María Uriarte, Grizelle González, Sasha Reed, J Thompson, Jess K Zimmerman, Lora Murphy
Tropical forests play a critical role in carbon and water cycles at a global scale. Rapid climate change is anticipated in tropical regions over the coming decades and, under a warmer and drier climate, tropical forests are likely to be net sources of carbon rather than sinks. However, our understanding of tropical forest response and feedback to climate change is very limited. Efforts to model climate change impacts on carbon fluxes in tropical forests have not reached a consensus. Here we use the Ecosystem Demography model (ED2) to predict carbon fluxes of a Puerto Rican tropical forest under realistic climate change scenarios...
August 14, 2017: Global Change Biology
https://www.readbyqxmd.com/read/28804834/one-stage-factor-viii-assays
#8
Elizabeth Duncan, Susan Rodgers
Coagulation factor assays using one-stage methodology are widely used to measure factor levels for the purpose of detecting a deficiency, or to monitor replacement therapy. In this chapter, we focus on a method to measure Factor VIII coagulant activity (FVIII:C) by the one-stage assay (FVIII:C-1), with extra information provided to also allow this method to apply to Factor IX (FIX), Factor XI (FXI), and Factor XII (FXII). From the perspective of laboratory testing, these factors are components of the "intrinsic" coagulation pathway and are all measured in test systems based on the correction of the Activated Partial Thromboplastin Time (APTT)...
2017: Methods in Molecular Biology
https://www.readbyqxmd.com/read/28804832/measuring-direct-oral-anticoagulants
#9
Robert C Gosselin, Jonathan Douxfils
Direct oral anticoagulants (DOACs) can be quantified using methods that can be performed in any clinical or research laboratory using manual or automated instrument platforms. Dabigatran etexilate, the oral direct thrombin inhibitor, can be quantified by drug-calibrated clot or chromogenic-based assays using either thrombin or ecarin as substrates. Oral direct anti-Xa inhibitors, such as rivaroxaban, apixaban, and edoxaban, can be quantified with drug-calibrated anti-Xa kits or reagents as typically used for measuring heparins (unfractionated, low molecular weight, or pentasaccharides)...
2017: Methods in Molecular Biology
https://www.readbyqxmd.com/read/28804727/development-of-a-prediction-model-for-stress-fracture-during-an-intensive-physical-training-program-the-royal-marines-commandos
#10
Maria T Sanchez-Santos, Trish Davey, Kirsten M Leyland, Adrian J Allsopp, Susan A Lanham-New, Andrew Judge, Nigel K Arden, Joanne L Fallowfield
BACKGROUND: Stress fractures (SFs) are one of the more severe overuse injuries in military training, and therefore, knowledge of potential risk factors is needed to assist in developing mitigating strategies. PURPOSE: To develop a prediction model for risk of SF in Royal Marines (RM) recruits during an arduous military training program. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: RM recruits (N = 1082; age range, 16-33 years) who enrolled between September 2009 and July 2010 were prospectively followed through the 32-week RM training program...
July 2017: Orthopaedic Journal of Sports Medicine
https://www.readbyqxmd.com/read/28804506/improved-k-t-pca-algorithm-using-artificial-sparsity-in-dynamic-mri
#11
Yiran Wang, Zhifeng Chen, Jing Wang, Lixia Yuan, Ling Xia, Feng Liu
The k-t principal component analysis (k-t PCA) is an effective approach for high spatiotemporal resolution dynamic magnetic resonance (MR) imaging. However, it suffers from larger residual aliasing artifacts and noise amplification when the reduction factor goes higher. To further enhance the performance of this technique, we propose a new method called sparse k-t PCA that combines the k-t PCA algorithm with an artificial sparsity constraint. It is a self-calibrated procedure that is based on the traditional k-t PCA method by further eliminating the reconstruction error derived from complex subtraction of the sampled k-t space from the original reconstructed k-t space...
2017: Computational and Mathematical Methods in Medicine
https://www.readbyqxmd.com/read/28803840/development-and-validation-of-risk-equations-for-complications-of-type-2-diabetes-recode-using-individual-participant-data-from-randomised-trials
#12
Sanjay Basu, Jeremy B Sussman, Seth A Berkowitz, Rodney A Hayward, John S Yudkin
BACKGROUND: In view of substantial mis-estimation of risks of diabetes complications using existing equations, we sought to develop updated Risk Equations for Complications Of type 2 Diabetes (RECODe). METHODS: To develop and validate these risk equations, we used data from the Action to Control Cardiovascular Risk in Diabetes study (ACCORD, n=9635; 2001-09) and validated the equations for microvascular events using data from the Diabetes Prevention Program Outcomes Study (DPPOS, n=1018; 1996-2001), and for cardiovascular events using data from the Action for Health in Diabetes (Look AHEAD, n=4760; 2001-12)...
August 10, 2017: Lancet Diabetes & Endocrinology
https://www.readbyqxmd.com/read/28803648/automated-multi-filtration-cleanup-with-nitrogen-enriched-activated-carbon-material-as-pesticide-multi-residue-analysis-method-in-representative-crop-commodities
#13
Yuhong Qin, Jingru Zhang, Yifan Li, Qiuxiao Wang, Yangliu Wu, Lanshu Xu, Xiaojuan Jin, Canping Pan
An automated multi-filtration cleanup (Auto m-FC) method with nitrogen-enriched activated carbon material based on modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) extracts was developed. It was applied to pesticide multi-residue analysis in six representative crop commodities. The automatic device was aimed to improve the cleanup efficiency and reduce manual operation workload in cleanup step. By controlling extracts volume, flow rate and Auto m-FC cycles, the device could finish cleanup process accurately...
August 5, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28803426/speciation-of-as-%C3%AE-%C3%AE-%C3%AE-as-v-and-total-inorganic-arsenic-in-biological-fluids-using-new-mode-of-liquid-phase-microextraction-and-electrothermal-atomic-absorption-spectrometry
#14
Lida Haghnazari, Nezam Mirzaei, Hossein Arfaeinia, Kamaladdin Karimyan, Hooshmand Sharafi, Nazir Fattahi
In this paper, a new extraction method based on countercurrent liquid-liquid microextraction (CLLME) has been developed for the extraction and preconcentration of inorganic arsenic (iAs) in plasma and urine samples prior to their analysis by electrothermal atomic absorption spectrometry (ETAAS). In this method, firstly, 5 ml of water is added to the extraction vessel. Then 30.0 μl of the extracting solvent is added to it in order for the extracting solvent to be placed in the narrow-necked vessel. In total, 10 ml of a standard solution or a pretreated real sample is added to the sample container and it is connected to the extraction vessel via a connector...
August 12, 2017: Biological Trace Element Research
https://www.readbyqxmd.com/read/28802520/an-analysis-of-long-term-ischemic-stroke-risk-in-survivors-of-septicemia
#15
Chun-An Cheng, Chun-Gu Cheng, Jiuun-Tay Lee, Hung-Che Lin, Cheng-Chung Cheng, Hung-Wen Chiu
INTRODUCTION: Sepsis increases the long-term incidence of ischemic stroke (IS). The chances for long-term IS in patients who are discharged after sepsis are unclear. Our aim was to demonstrate long-term risk chances of IS after septicemia discharge. We used a nomogram to identify those septicemia survivors with the higher risk of developing IS. METHODS: Inpatient data were used from the Taiwan Longitudinal Health Insurance Database, from 2001 to 2003. The event was IS rehospitalization after discharge of septicemia...
August 9, 2017: Journal of Stroke and Cerebrovascular Diseases: the Official Journal of National Stroke Association
https://www.readbyqxmd.com/read/28801822/simultaneous-quantification-of-free-cholesterol-cholesteryl-esters-and-triglycerides-without-ester-hydrolysis-by-uhplc-separation-and-in-source-collision-induced-dissociation-coupled-ms-ms
#16
Michael S Gardner, Lisa G McWilliams, Jeffrey I Jones, Zsuzsanna Kuklenyik, James L Pirkle, John R Barr
We demonstrate the application of in-source nitrogen collision-induced dissociation (CID) that eliminates the need for ester hydrolysis before simultaneous analysis of esterified cholesterol (EC) and triglycerides (TG) along with free cholesterol (FC) from human serum, using normal phase liquid chromatography (LC) coupled to atmospheric pressure chemical ionization (APCI) tandem mass spectrometry (MS/MS). The analysis requires only 50 μL of 1:100 dilute serum with a high-throughput, precipitation/evaporation/extraction protocol in one pot...
August 11, 2017: Journal of the American Society for Mass Spectrometry
https://www.readbyqxmd.com/read/28801777/an-internally-validated-new-clinical-and-inflammation-based-prognostic-score-for-patients-with-advanced-hepatocellular-carcinoma-treated-with-sorafenib
#17
R Diaz-Beveridge, G Bruixola, D Lorente, J Caballero, E Rodrigo, Á Segura, D Akhoundova, A Giménez, J Aparicio
BACKGROUND: Sorafenib is a standard treatment for patients (pts) with advanced hepatocellular carcinoma (aHCC), although the clinical benefit is heterogeneous between different pts groups. Among novel prognostic factors, a low baseline neutrophil-to-lymphocyte ratio (bNLR) and early-onset diarrhoea have been linked with a better prognosis. PURPOSE: To identify prognostic factors in pts with aHCC treated with 1st-line sorafenib and to develop a new prognostic score to guide management...
August 11, 2017: Clinical & Translational Oncology
https://www.readbyqxmd.com/read/28801646/a-new-treatment-integrated-prognostic-nomogram-of-the-barcelona-clinic-liver-cancer-system-for-hepatocellular-carcinoma
#18
Chia-Yang Hsu, Po-Hong Liu, Cheng-Yuan Hsia, Yun-Hsuan Lee, Teddy S Nagaria, Rheun-Chuan Lee, Shu-Yein Ho, Ming-Chih Hou, Teh-Ia Huo
The nomogram of the Barcelona Clinic Liver Cancer (BCLC) has accurate outcome prediction. This study aims to propose a treatment-integrated nomogram derived from BCLC for patients with hepatocellular carcinoma (HCC). A total of 3,371 patients were randomly grouped into derivation (n = 2,247) and validation (n = 1,124) sets. Multivariate Cox proportional hazards model was used to generate the nomogram from tumor burden, cirrhosis, performance status (PS) and primary anti-cancer treatments. Concordance indices and calibration plots were used to evaluate the performance of nomogram...
August 11, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28801617/g-protein-stoichiometry-dictates-biased-agonism-through-distinct-receptor-g-protein-partitioning
#19
Lauriane Onfroy, Ségolène Galandrin, Stéphanie M Pontier, Marie-Hélène Seguelas, Du N'Guyen, Jean-Michel Sénard, Céline Galés
Biased agonism at G protein coupled receptors emerges as an opportunity for development of drugs with enhanced benefit/risk balance making biased ligand identification a priority. However, ligand biased signature, classically inferred from ligand activity across multiple pathways, displays high variability in recombinant systems. Functional assays usually necessity receptor/effector overexpression that should be controlled among assays to allow comparison but this calibration currently fails. Herein, we demonstrate that Gα expression level dictates the biased profiling of agonists and, to a lesser extent of β-blockers, in a Gα isoform- and receptor-specific way, depending on specific G protein activity in different membrane territories...
August 11, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28801147/variability-in-split-thickness-skin-graft-depth-when-using-an-air-powered-dermatome-a-paediatric-cohort-study
#20
Craig A McBride, Margit Kempf, Roy M Kimble, Kellie Stockton
AIM: Split-thickness skin grafts (STSG) taken using calibrated powered dermatomes are assumed to yield a graft of uniform thickness, though this assumption has never been analysed statistically. This study aims to test that assumption in a paediatric population. METHOD: STSGs from a consecutive cohort of paediatric patients were analysed for mean thickness, measured from a central biopsy. All STSGs were taken from the thigh at a dialled thickness of 0.007in. Data were analysed using non-parametric methods...
August 8, 2017: Burns: Journal of the International Society for Burn Injuries
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