meth Pac-12 basketball tournament starts, but there's something missing By www.latimes.com Published On :: Wed, 11 Mar 2020 17:25:14 -0400 The Pac-12 men's basketball tournament began Wednesday in Las Vegas amid coronavirus concerns. UCLA and other schools opted not to send bands. Full Article
meth Even with no games, something fun is Bruin with UCLA announcer Josh Lewin By www.latimes.com Published On :: Mon, 23 Mar 2020 19:01:32 -0400 Longtime UCLA broadcaster Josh Lewin has found ways to utilize his talent while the sports world is on pause because of the coronavirus pandemic. Full Article
meth Lyle Mays, keyboardist and co-founder of Pat Metheny Group, dies at 66 By www.latimes.com Published On :: Wed, 12 Feb 2020 15:47:18 -0500 The jazz musician's work won nearly a dozen Grammy Awards. Full Article
meth Op-Ed: Biden should play up his expertise, since it's something Trump lacks By www.latimes.com Published On :: Fri, 1 May 2020 06:00:10 -0400 In these troubled times, experience rather than populist appeal is what voters will want when they choose a president in November. Full Article
meth Charlie Methven net worth: How much is the former Sunderland director worth? By www.express.co.uk Published On :: Wed, 22 Apr 2020 18:01:00 +0100 Charlie Methven features prominently in the new season of Sunderland 'Til I Die - but how much is the club's former executive director worth? Full Article
meth The pandemic offers mothers something they will never have again By rssfeeds.usatoday.com Published On :: Sat, 09 May 2020 13:38:40 +0000 The pandemic has undoubtedly created parental suffering, but it also offers an opportunity to be present with our children in ways we never could. Full Article
meth For Plainfield inmates, gardening is 'something positive in a kind of negative environment' By rssfeeds.indystar.com Published On :: Mon, 29 Jul 2019 14:25:31 +0000 Plainfield Correctional Facility inmates donate fruits and vegetables from their garden to community organizations. Full Article
meth 'Slow-rolling disaster': Exclusive look inside the coronavirus units at IU Health Methodist Hospital By rssfeeds.indystar.com Published On :: Fri, 08 May 2020 19:20:08 +0000 IndyStar went inside IU Health Methodist Hospital for an exclusive look at its COVID-19 units in the midst of the coronavirus pandemic. Full Article
meth Rush Limbaugh Predicts Joe Biden Won’t Be The Dem Nominee: “Something’s Gonna Happen” By 100percentfedup.com Published On :: Sat, 09 May 2020 02:15:43 +0000 The following article, Rush Limbaugh Predicts Joe Biden Won’t Be The Dem Nominee: “Something’s Gonna Happen”, was first published on 100PercentFedUp.com. Is Joe Biden going to become the Democrat nominee and run against Trump in the fall? Continue reading: Rush Limbaugh Predicts Joe Biden Won’t Be The Dem Nominee: “Something’s Gonna Happen” ... Full Article Featured Left News Politics
meth Structure-based discovery of a small-molecule inhibitor of methicillin-resistant Staphylococcus aureus virulence [Molecular Biophysics] By feedproxy.google.com Published On :: 2020-05-01T00:06:09-07:00 The rapid emergence and dissemination of methicillin-resistant Staphylococcus aureus (MRSA) strains poses a major threat to public health. MRSA possesses an arsenal of secreted host-damaging virulence factors that mediate pathogenicity and blunt immune defenses. Panton–Valentine leukocidin (PVL) and α-toxin are exotoxins that create lytic pores in the host cell membrane. They are recognized as being important for the development of invasive MRSA infections and are thus potential targets for antivirulence therapies. Here, we report the high-resolution X-ray crystal structures of both PVL and α-toxin in their soluble, monomeric, and oligomeric membrane-inserted pore states in complex with n-tetradecylphosphocholine (C14PC). The structures revealed two evolutionarily conserved phosphatidylcholine-binding mechanisms and their roles in modulating host cell attachment, oligomer assembly, and membrane perforation. Moreover, we demonstrate that the soluble C14PC compound protects primary human immune cells in vitro against cytolysis by PVL and α-toxin and hence may serve as the basis for the development of an antivirulence agent for managing MRSA infections. Full Article
meth Comparison of Label-free Methods for Quantifying Human Proteins by Shotgun Proteomics By feedproxy.google.com Published On :: 2005-10-01 William M. OldOct 1, 2005; 4:1487-1502Research Full Article
meth Virtual Roundtable: Evaluating Outcomes in Fragile Contexts: Adapting Research Methods in the Time of COVID-19 By feedproxy.google.com Published On :: Mon, 04 May 2020 08:55:01 +0000 Invitation Only Research Event 5 May 2020 - 12:00pm to 1:00pm Agendapdf | 107.59 KB Event participants Rebecca Wolfe, Lecturer, Harris School for Public Policy and Associate, Pearson Institute for the Study and Resolution of Global Conflicts, University of ChicagoTom Gillhespy, Principal Consultant, ItadShodmon Hojibekov, Chief Executive Officer, Aga Khan Agency for Habitat (Afghanistan)Chair: Champa Patel, Director, Asia-Pacific Programme, Chatham House This virtual roundtable has been co-convened by Chatham House and the Aga Khan Foundation. While conducting research in fragile and conflict-affected contexts has always presented challenges, the outbreak of COVID-19 creates additional challenges including travel restrictions, ethical challenges, and disruptions to usual modes of working. This virtual roundtable will explore how organizations can adapt their research and monitoring and evaluation models in response to the coronavirus pandemic. This event aims to discuss the research methods being used to mitigate the impact of the COVID-19 crisis; the important role of technology; and ways to engage policy and decision-makers during this time. Event attributes Chatham House Rule Department/project Asia-Pacific Programme, Conflict, Peace and Stability, Geopolitics and Governance Lucy Ridout Programme Administrator, Asia-Pacific Programme +44 (0) 207 314 2761 Email Full Article
meth A simplified method for the preparation of detergent-free lipid rafts By feedproxy.google.com Published On :: 2005-05-01 Jennifer L. MacdonaldMay 1, 2005; 46:1061-1067Methods Full Article
meth Rapid method for the isolation of lipoproteins from human serum by precipitation with polyanions By feedproxy.google.com Published On :: 1970-11-01 M. BursteinNov 1, 1970; 11:583-595Articles Full Article
meth Lipid extraction by methyl-tert-butyl ether for high-throughput lipidomics By feedproxy.google.com Published On :: 2008-05-01 Vitali MatyashMay 1, 2008; 49:1137-1146Methods Full Article
meth Preparation of fatty acid methyl esters and dimethylacetals from lipids with boron fluoride--methanol By feedproxy.google.com Published On :: 1964-10-01 William R. MorrisonOct 1, 1964; 5:600-608Articles Full Article
meth Virtual Roundtable: Evaluating Outcomes in Fragile Contexts: Adapting Research Methods in the Time of COVID-19 By feedproxy.google.com Published On :: Mon, 04 May 2020 08:55:01 +0000 Invitation Only Research Event 5 May 2020 - 12:00pm to 1:00pm Agendapdf | 107.59 KB Event participants Rebecca Wolfe, Lecturer, Harris School for Public Policy and Associate, Pearson Institute for the Study and Resolution of Global Conflicts, University of ChicagoTom Gillhespy, Principal Consultant, ItadShodmon Hojibekov, Chief Executive Officer, Aga Khan Agency for Habitat (Afghanistan)Chair: Champa Patel, Director, Asia-Pacific Programme, Chatham House This virtual roundtable has been co-convened by Chatham House and the Aga Khan Foundation. While conducting research in fragile and conflict-affected contexts has always presented challenges, the outbreak of COVID-19 creates additional challenges including travel restrictions, ethical challenges, and disruptions to usual modes of working. This virtual roundtable will explore how organizations can adapt their research and monitoring and evaluation models in response to the coronavirus pandemic. This event aims to discuss the research methods being used to mitigate the impact of the COVID-19 crisis; the important role of technology; and ways to engage policy and decision-makers during this time. Event attributes Chatham House Rule Department/project Asia-Pacific Programme, Conflict, Peace and Stability, Geopolitics and Governance Lucy Ridout Programme Administrator, Asia-Pacific Programme +44 (0) 207 314 2761 Email Full Article
meth Cybersecurity Series: Exploring Methods of Internet Censorship and Control By feedproxy.google.com Published On :: Thu, 14 Mar 2019 00:00:00 +0000 Full Article
meth Structure-based discovery of a small-molecule inhibitor of methicillin-resistant Staphylococcus aureus virulence [Molecular Biophysics] By feedproxy.google.com Published On :: 2020-05-01T00:06:09-07:00 The rapid emergence and dissemination of methicillin-resistant Staphylococcus aureus (MRSA) strains poses a major threat to public health. MRSA possesses an arsenal of secreted host-damaging virulence factors that mediate pathogenicity and blunt immune defenses. Panton–Valentine leukocidin (PVL) and α-toxin are exotoxins that create lytic pores in the host cell membrane. They are recognized as being important for the development of invasive MRSA infections and are thus potential targets for antivirulence therapies. Here, we report the high-resolution X-ray crystal structures of both PVL and α-toxin in their soluble, monomeric, and oligomeric membrane-inserted pore states in complex with n-tetradecylphosphocholine (C14PC). The structures revealed two evolutionarily conserved phosphatidylcholine-binding mechanisms and their roles in modulating host cell attachment, oligomer assembly, and membrane perforation. Moreover, we demonstrate that the soluble C14PC compound protects primary human immune cells in vitro against cytolysis by PVL and α-toxin and hence may serve as the basis for the development of an antivirulence agent for managing MRSA infections. Full Article
meth Tracking isotopically labeled oxidants using boronate-based redox probes [Methods and Resources] By feedproxy.google.com Published On :: 2020-05-08T03:41:14-07:00 Reactive oxygen and nitrogen species have been implicated in many biological processes and diseases, including immune responses, cardiovascular dysfunction, neurodegeneration, and cancer. These chemical species are short-lived in biological settings, and detecting them in these conditions and diseases requires the use of molecular probes that form stable, easily detectable, products. The chemical mechanisms and limitations of many of the currently used probes are not well-understood, hampering their effective applications. Boronates have emerged as a class of probes for the detection of nucleophilic two-electron oxidants. Here, we report the results of an oxygen-18–labeling MS study to identify the origin of oxygen atoms in the oxidation products of phenylboronate targeted to mitochondria. We demonstrate that boronate oxidation by hydrogen peroxide, peroxymonocarbonate, hypochlorite, or peroxynitrite involves the incorporation of oxygen atoms from these oxidants. We therefore conclude that boronates can be used as probes to track isotopically labeled oxidants. This suggests that the detection of specific products formed from these redox probes could enable precise identification of oxidants formed in biological systems. We discuss the implications of these results for understanding the mechanism of conversion of the boronate-based redox probes to oxidant-specific products. Full Article
meth Virtual Roundtable: Evaluating Outcomes in Fragile Contexts: Adapting Research Methods in the Time of COVID-19 By feedproxy.google.com Published On :: Mon, 04 May 2020 08:55:01 +0000 Invitation Only Research Event 5 May 2020 - 12:00pm to 1:00pm Agendapdf | 107.59 KB Event participants Rebecca Wolfe, Lecturer, Harris School for Public Policy and Associate, Pearson Institute for the Study and Resolution of Global Conflicts, University of ChicagoTom Gillhespy, Principal Consultant, ItadShodmon Hojibekov, Chief Executive Officer, Aga Khan Agency for Habitat (Afghanistan)Chair: Champa Patel, Director, Asia-Pacific Programme, Chatham House This virtual roundtable has been co-convened by Chatham House and the Aga Khan Foundation. While conducting research in fragile and conflict-affected contexts has always presented challenges, the outbreak of COVID-19 creates additional challenges including travel restrictions, ethical challenges, and disruptions to usual modes of working. This virtual roundtable will explore how organizations can adapt their research and monitoring and evaluation models in response to the coronavirus pandemic. This event aims to discuss the research methods being used to mitigate the impact of the COVID-19 crisis; the important role of technology; and ways to engage policy and decision-makers during this time. Event attributes Chatham House Rule Department/project Asia-Pacific Programme, Conflict, Peace and Stability, Geopolitics and Governance Lucy Ridout Programme Administrator, Asia-Pacific Programme +44 (0) 207 314 2761 Email Full Article
meth Creating Something out of (Next to) Nothing By www.ams.org Published On :: Fri, 10 Dec 2010 14:45:24 -0500 Normally when creating a digital file, such as a picture, much more information is recorded than necessary-even before storing or sending. The image on the right was created with compressed (or compressive) sensing, a breakthrough technique based on probability and linear algebra. Rather than recording excess information and discarding what is not needed, sensors collect the most significant information at the time of creation, which saves power, time, and memory. The potential increase in efficiency has led researchers to investigate employing compressed sensing in applications ranging from missions in space, where minimizing power consumption is important, to MRIs, for which faster image creation would allow for better scans and happier patients. Just as a word has different representations in different languages, signals (such as images or audio) can be represented many different ways. Compressed sensing relies on using the representation for the given class of signals that requires the fewest bits. Linear programming applied to that representation finds the most likely candidate fitting the particular low-information signal. Mathematicians have proved that in all but the very rarest case that candidate-often constructed from less than a tiny fraction of the data traditionally collected-matches the original. The ability to locate and capture only the most important components without any loss of quality is so unexpected that even the mathematicians who discovered compressed sensing found it hard to believe. For More Information: "Compressed Sensing Makes Every Pixel Count," What's Happening in the Mathematical Sciences, Vol. 7, Dana Mackenzie. Full Article
meth What is the fast back links generation method? By forums.digitalpoint.com Published On :: Sat, 09 May 2020 11:03:49 +0000 Full Article
meth Something for copywriters to enjoy! By forums.digitalpoint.com Published On :: Sat, 09 May 2020 16:37:11 +0000 Full Article
meth CBD News: Seminar-Workshop on Harmonizing Methods in Risk Assessment and Management of Forest Invasive Alien Plant Species in South East Asia, 2-5 December 2014, Bogor, Indonesia By www.cbd.int Published On :: Tue, 02 Dec 2014 00:00:00 GMT Full Article
meth CBD News: Rachel Carson, the late American biologist and conservationist, suggested "there is symbolic as well as actual beauty in the migration of the birds... something infinitely healing in the repeated refrains of nature - the assurance that dawn By www.cbd.int Published On :: Fri, 11 May 2018 00:00:00 GMT Full Article
meth CBD Notification SCBD/IMS/JMF/NVW/86292 (2019-117): Follow-up invitation to participate in and/or contribute to the piloting and further development of a methodology for the voluntary peer review of national biodiversity strategies and action plans By www.cbd.int Published On :: Wed, 18 Dec 2019 00:00:00 GMT Full Article
meth Cubature method to solve BSDEs: Error expansion and complexity control By www.ams.org Published On :: Tue, 07 Apr 2020 14:09 EDT Jean-Francois Chassagneux and Camilo A. Garcia Trillos Math. Comp. 89 (2020), 1895-1932. Abstract, references and article information Full Article
meth High order explicit local time stepping methods for hyperbolic conservation laws By www.ams.org Published On :: Tue, 07 Apr 2020 14:09 EDT Thi-Thao-Phuong Hoang, Lili Ju, Wei Leng and Zhu Wang Math. Comp. 89 (2020), 1807-1842. Abstract, references and article information Full Article
meth Nonconforming Virtual Element Method for 2????th Order Partial Differential Equations in ℝⁿ By www.ams.org Published On :: Tue, 07 Apr 2020 14:09 EDT Long Chen and Xuehai Huang Math. Comp. 89 (2019), 1711-1744. Abstract, references and article information Full Article
meth A finite element data assimilation method for the wave equation By www.ams.org Published On :: Tue, 07 Apr 2020 14:09 EDT Erik Burman, Ali Feizmohammadi and Lauri Oksanen Math. Comp. 89 (2020), 1681-1709. Abstract, references and article information Full Article
meth Probabilistic Methods in Geometry, Topology and Spectral Theory By www.ams.org Published On :: Fri, 22 Nov 2019 09:41 EST Yaiza Canzani, Linan Chen and Dmitry Jakobson, editors. American Mathematical Society | Centre de Recherches Mathematiques, 2019, CONM, volume 739, approx. 208 pp. ISBN: 978-1-4704-4145-6 (print), 978-1-4704-5599-6 (online). This volume contains the proceedings of the CRM Workshops on Probabilistic Methods in Spectral Geometry and PDE, held from August 22–26, 2016 and... Full Article
meth Analytic Methods in Arithmetic Geometry By www.ams.org Published On :: Thu, 26 Dec 2019 09:58 EST Alina Bucur and David Zureick-Brown, editors. American Mathematical Society | Centre de Recherches Mathematiques, 2019, CONM, volume 740, approx. 256 pp. ISBN: 978-1-4704-3784-8 (print), 978-1-4704-5629-0 (online). This volume contains the proceedings of the Arizona Winter School 2016, which was held from March 12–16, 2016, at The University of Arizona,... Full Article
meth Orthogonal regression method for observations from a mixture By www.ams.org Published On :: Mon, 02 Mar 2020 06:58 EST R. E. Maĭboroda, G. V. Navara and O. V. Sugakova Theor. Probability and Math. Statist. 99 (2020), 169-188. Abstract, references and article information Full Article
meth New simple method for measuring the state of lithium-ion batteries By www.eurekalert.org Published On :: Thu, 07 May 2020 00:00:00 EDT (Johannes Gutenberg Universitaet Mainz) Scientists at Johannes Gutenberg University Mainz (JGU) and the Helmholtz Institute Mainz (HIM) in Germany have presented a non-contact method for detecting the state of charge and any defects in lithium-ion batteries. Full Article
meth Development of a novel {beta}-1,6-glucan-specific detection system using functionally-modified recombinant endo-{beta}-1,6-glucanase [Methods and Resources] By www.jbc.org Published On :: 2020-04-17T00:06:05-07:00 β-1,3-d-Glucan is a ubiquitous glucose polymer produced by plants, bacteria, and most fungi. It has been used as a diagnostic tool in patients with invasive mycoses via a highly-sensitive reagent consisting of the blood coagulation system of horseshoe crab. However, no method is currently available for measuring β-1,6-glucan, another primary β-glucan structure of fungal polysaccharides. Herein, we describe the development of an economical and highly-sensitive and specific assay for β-1,6-glucan using a modified recombinant endo-β-1,6-glucanase having diminished glucan hydrolase activity. The purified β-1,6-glucanase derivative bound to the β-1,6-glucan pustulan with a KD of 16.4 nm. We validated the specificity of this β-1,6-glucan probe by demonstrating its ability to detect cell wall β-1,6-glucan from both yeast and hyphal forms of the opportunistic fungal pathogen Candida albicans, without any detectable binding to glucan lacking the long β-1,6-glucan branch. We developed a sandwich ELISA-like assay with a low limit of quantification for pustulan (1.5 pg/ml), and we successfully employed this assay in the quantification of extracellular β-1,6-glucan released by >250 patient-derived strains of different Candida species (including Candida auris) in culture supernatant in vitro. We also used this assay to measure β-1,6-glucan in vivo in the serum and in several organs in a mouse model of systemic candidiasis. Our work describes a reliable method for β-1,6-glucan detection, which may prove useful for the diagnosis of invasive fungal infections. Full Article
meth MtrP, a putative methyltransferase in Corynebacteria, is required for optimal membrane transport of trehalose mycolates [Lipids] By www.jbc.org Published On :: 2020-05-01T00:06:09-07:00 Pathogenic bacteria of the genera Mycobacterium and Corynebacterium cause severe human diseases such as tuberculosis (Mycobacterium tuberculosis) and diphtheria (Corynebacterium diphtheriae). The cells of these species are surrounded by protective cell walls rich in long-chain mycolic acids. These fatty acids are conjugated to the disaccharide trehalose on the cytoplasmic side of the bacterial cell membrane. They are then transported across the membrane to the periplasm where they act as donors for other reactions. We have previously shown that transient acetylation of the glycolipid trehalose monohydroxycorynomycolate (hTMCM) enables its efficient transport to the periplasm in Corynebacterium glutamicum and that acetylation is mediated by the membrane protein TmaT. Here, we show that a putative methyltransferase, encoded at the same genetic locus as TmaT, is also required for optimal hTMCM transport. Deletion of the C. glutamicum gene NCgl2764 (Rv0224c in M. tuberculosis) abolished acetyltrehalose monocorynomycolate (AcTMCM) synthesis, leading to accumulation of hTMCM in the inner membrane and delaying its conversion to trehalose dihydroxycorynomycolate (h2TDCM). Complementation with NCgl2764 normalized turnover of hTMCM to h2TDCM. In contrast, complementation with NCgl2764 derivatives mutated at residues essential for methyltransferase activity failed to rectify the defect, suggesting that NCgl2764/Rv0224c encodes a methyltransferase, designated here as MtrP. Comprehensive analyses of the individual mtrP and tmaT mutants and of a double mutant revealed strikingly similar changes across several lipid classes compared with WT bacteria. These findings indicate that both MtrP and TmaT have nonredundant roles in regulating AcTMCM synthesis, revealing additional complexity in the regulation of trehalose mycolate transport in the Corynebacterineae. Full Article
meth Structure-based discovery of a small-molecule inhibitor of methicillin-resistant Staphylococcus aureus virulence [Molecular Biophysics] By www.jbc.org Published On :: 2020-05-01T00:06:09-07:00 The rapid emergence and dissemination of methicillin-resistant Staphylococcus aureus (MRSA) strains poses a major threat to public health. MRSA possesses an arsenal of secreted host-damaging virulence factors that mediate pathogenicity and blunt immune defenses. Panton–Valentine leukocidin (PVL) and α-toxin are exotoxins that create lytic pores in the host cell membrane. They are recognized as being important for the development of invasive MRSA infections and are thus potential targets for antivirulence therapies. Here, we report the high-resolution X-ray crystal structures of both PVL and α-toxin in their soluble, monomeric, and oligomeric membrane-inserted pore states in complex with n-tetradecylphosphocholine (C14PC). The structures revealed two evolutionarily conserved phosphatidylcholine-binding mechanisms and their roles in modulating host cell attachment, oligomer assembly, and membrane perforation. Moreover, we demonstrate that the soluble C14PC compound protects primary human immune cells in vitro against cytolysis by PVL and α-toxin and hence may serve as the basis for the development of an antivirulence agent for managing MRSA infections. Full Article
meth About the cover: The Fine–Petrović Polygons and the Newton–Puiseux Method for Algebraic Ordinary Differential Equations By www.ams.org Published On :: Fri, 13 Mar 2020 16:19 EDT Vladimir Dragović and Irina Goryuchkina Bull. Amer. Math. Soc. 57 (2020), 293-299. Abstract, references and article information Full Article
meth MtrP, a putative methyltransferase in Corynebacteria, is required for optimal membrane transport of trehalose mycolates [Lipids] By feedproxy.google.com Published On :: 2020-05-01T00:06:09-07:00 Pathogenic bacteria of the genera Mycobacterium and Corynebacterium cause severe human diseases such as tuberculosis (Mycobacterium tuberculosis) and diphtheria (Corynebacterium diphtheriae). The cells of these species are surrounded by protective cell walls rich in long-chain mycolic acids. These fatty acids are conjugated to the disaccharide trehalose on the cytoplasmic side of the bacterial cell membrane. They are then transported across the membrane to the periplasm where they act as donors for other reactions. We have previously shown that transient acetylation of the glycolipid trehalose monohydroxycorynomycolate (hTMCM) enables its efficient transport to the periplasm in Corynebacterium glutamicum and that acetylation is mediated by the membrane protein TmaT. Here, we show that a putative methyltransferase, encoded at the same genetic locus as TmaT, is also required for optimal hTMCM transport. Deletion of the C. glutamicum gene NCgl2764 (Rv0224c in M. tuberculosis) abolished acetyltrehalose monocorynomycolate (AcTMCM) synthesis, leading to accumulation of hTMCM in the inner membrane and delaying its conversion to trehalose dihydroxycorynomycolate (h2TDCM). Complementation with NCgl2764 normalized turnover of hTMCM to h2TDCM. In contrast, complementation with NCgl2764 derivatives mutated at residues essential for methyltransferase activity failed to rectify the defect, suggesting that NCgl2764/Rv0224c encodes a methyltransferase, designated here as MtrP. Comprehensive analyses of the individual mtrP and tmaT mutants and of a double mutant revealed strikingly similar changes across several lipid classes compared with WT bacteria. These findings indicate that both MtrP and TmaT have nonredundant roles in regulating AcTMCM synthesis, revealing additional complexity in the regulation of trehalose mycolate transport in the Corynebacterineae. Full Article
meth DEqMS: a method for accurate variance estimation in differential protein expression analysis By feedproxy.google.com Published On :: 2020-03-23 Yafeng ZhuMar 23, 2020; 0:TIR119.001646v1-mcp.TIR119.001646Technological Innovation and Resources Full Article
meth Evaluation of dosimetry, quantitative methods and test-retest variability of 18F-PI-2620 PET for the assessment of tau deposits in the human brain By jnm.snmjournals.org Published On :: 2019-11-11T12:55:20-08:00 18F-PI-2620 is a next generation tau positron emission tomography (PET)-tracer that has demonstrated ability to image the spatial distribution of suspected tau pathology. The objective of this study was to assess the tracer biodistribution, dosimetry and quantitative methods of 18F-PI-2620 in the human brain. Full kinetic modelling approaches to quantify tau load were investigated. Non-invasive kinetic modeling approaches and semi-quantitative methods were evaluated against the full tracer kinetics. Finally, the reproducibility of PET measurements from test and retest scans was assessed. Methods: Three healthy controls (HC) and 4 Alzheimer disease (AD) subjects underwent two dynamic PET scans including arterial sampling. Distribution volume ratio (DVR) was estimated using full tracer kinetics (2 Tissue Compartment (2TC) models, Logan Graphical Analysis (LGA)) and non-invasive kinetic models (Non-Invasive Logan Graphical Analysis (NI-LGA) and the multilinear reference tissue model (MRTM2)). Standardized uptake value ratio (SUVR) was determined at different imaging windows after injection. Correlation between DVR and SUVR, effect size (Cohen’s d) and test-retest variability (TRV) were evaluated. Additionally, 6 HC subjects received one tracer administration and underwent whole-body PET for dosimetry calculation. Organ doses and the whole-body effective dose were calculated using OLINDA 2.0. Results: Strong correlation was found across different kinetic models (R2 >0.97) and between DVR(2TC) and SUVRs between 30 to 90 min with R2>0.95. Secular equilibrium was reached around 40 min post injection (p.i.) in most regions and subjects. The TRV and effect size for the SUVR across different regions was similar at 30-60 min (TRV=3.8%, d=3.80), 45-75 min (TRV=4.3%, d=3.77) and 60-90 min (TRV=4.9%, d=3.73) and increased at later time points. Elimination was via the hepatobiliary and urinary system. The whole-body effective dose was determined to be 33.3±2.1 μSv/MBq for an adult female and 33.1±1.4 μSv/MBq for an adult male with a 1.5 hour urinary bladder voiding interval. Conclusion: 18F-PI-2620 exhibits fast kinetics, suitable dosimetry and low TRV. DVR measured using the 2TC model with arterial sampling correlated strongly with DVR measured by NI-LGA, MRTM2 and SUVR. SUVR can be used for 18F-PI-2620 PET quantification of tau deposits avoiding arterial blood sampling. Static 18F-PI-2620 PET scans between 45-75min p.i. provide excellent quantification accuracy, large effect size and low TRV. Full Article
meth Radiation Dosimetry in 177Lu-PSMA-617 Therapy Using a Single Post-treatment SPECT/CT: A Novel Methodology to Generate Time- and Tissue-specific Dose Factors By jnm.snmjournals.org Published On :: 2019-12-05T10:37:41-08:00 Calculation of radiation dosimetry in targeted nuclear medicine therapies is traditionally resource-intensive requiring multiple post-therapy SPECT acquisitions. An alternative approach is to take advantage of existing pharmacokinetic data from these smaller cohorts to enable dose computation from a single post-treatment scan in a manner that may be applied to a much broader patient population. Methods: In this work, a technical description for simplified dose estimation is presented and applied to assessment of 177Lu-PSMA-617 therapy (Prostate-Specific Membrane Antigen) for metastatic prostate cancer. By normalizing existing time-activity curves to a single measurement time, it is possible to calculate a mean and range of time-integrated activity values which relate to radiation absorbed dose. To assist with accurate pharmacokinetic modelling of the training cohort, a method for contour-guided image registration was developed. Results: Tissue-specific dose conversion factors for common post-treatment imaging times are reported along with a characterization of added uncertainty in comparison to a traditional serial imaging protocol. Single time point dose factors for tumor were determined to be 11.0, 12.1, 13.6, and 15.2 Gy per MBq/mL at image times of 24, 48, 72, and 96 hours, respectively. For normal tissues, parotid gland factors were 6.7, 9.4, 13.3, and 19.3 Gy per MBq/mL and kidneys were 7.1, 10.3, 15.0, and 22.0 Gy per MBq/mL at those times. Tumor dose estimates were most accurate using delayed scanning at times beyond 72 hours. Dose to healthy tissues is best characterized by scanning patients in the first two days of treatment owing to the larger degree of tracer clearance in this early phase. Conclusion: The work demonstrates a means for efficient dose estimation in 177Lu-PSMA-617 therapy. By providing methods to simplify and potentially automate radiation dosimetry we hope to accelerate the understanding of radiobiology and development of dose-response models in this unique therapeutic context. Full Article
meth 11C-Methionine PET Identifies Astroglia Involvement in Heart-Brain Inflammation Networking after Acute Myocardial Infarction By jnm.snmjournals.org Published On :: 2019-12-05T10:37:41-08:00 Acute myocardial infarction (MI) triggers a local and systemic inflammatory response. We recently showed microglia involvement using TSPO imaging. Here, we evaluate whether 11C-methionine provides further insights into heart-brain inflammation networking. Methods: Male Bl6N mice underwent permanent coronary artery ligation followed by 11C-methionine PET at 3 and 7 days (n = 3). In subgroups, leukocyte homing was blocked by integrin antibodies (n = 5). The cellular substrate for PET signal was identified using brain section immunostaining. Results: 11C-methionine uptake peaked in the MI region at d3 (5.9±0.9vs 2.4±0.5 %ID/cc), decreasing to control level by d7 (4.3±0.6 %ID/cc). Brain uptake was proportional to cardiac uptake (r=0.47,p<0.05), peaking also at d3 (2.9±0.4vs 2.4±0.3 %ID/cc) and returning to baseline at d7 (2.3±0.4 %ID/cc). Integrin blockade reduced uptake at every time point. Immunostaining at d3 revealed co-localization of the L-type amino acid transporter with GFAP-positive astrocytes but not CD68-positive microglia. Conclusion: PET imaging with 11C-methionine specifically identifies an astrocyte component, enabling further dissection of the heart-brain axis in post MI inflammation. Full Article
meth Confirmation of 123I-FP-CIT-SPECT (ioflupane) quantification methods in dementia with Lewy body and other neurodegenerative disorders By jnm.snmjournals.org Published On :: 2020-05-08T13:18:58-07:00 Rationale: To conduct a retrospective study comparing three 123I-FP-CIT-SPECT quantitative methods in patients with neurodegenerative syndromes as referenced to neuropathological findings. Methods: 123I-FP-CIT-SPECT and neuropathological findings among patients with neurodegenerative syndromes from the Mayo Alzheimer's Disease Research Center and Mayo Clinic Study of Aging were examined. Three 123I-FP-CIT-SPECT quantitative assessment Methods: MIMneuro (MIM Software Inc.), DaTQUANT (GE Healthcare), and manual region of interest (ROI) creation on an Advantage Workstation (GE Healthcare) were compared to neuropathological findings describing the presence or absence of Lewy body disease (LBD). Striatum to background ratios (SBRs) generated by DaTQUANT were compared to the calculated SBRs of the manual method and MIMneuro. The left and right SBRs for caudate, putamen and striatum were evaluated with the manual method. For DaTQUANT and MIMneuro the left, right, total and average SBRs and z-scores for whole striatum, caudate, putamen, anterior putamen, and posterior putamen were calculated. Results: The cohort included 24 patients [20 (83%) male, aged 75.4 +/- 10.0 at death]. The antemortem clinical diagnoses were Alzheimer’s disease dementia (ADem, N = 6), probable dementia with Lewy bodies (pDLB, N = 12), mixed ADem/pDLB (N = 1), Parkinson’s disease with mild cognitive impairment (N = 2), corticobasal syndrome (N = 1), idiopathic rapid eye movement sleep behavior disorder (iRBD) (N = 1) and behavioral variant frontotemporal dementia (N = 1). Seventeen (71%) had LBD pathology. All three 123I-FP-CIT-SPECT quantitative methods had area under the receiver operating characteristics (AUROC) values above 0.93 and up to 1.000 (p<0.001) and showed excellent discrimination between LBD and non-LBD patients in each region assessed, p<.001. There was no significant difference between the accuracy of the regions in discriminating the two groups, with good discrimination for both caudate and putamen. Conclusion: All three 123I-FP-CIT-SPECT quantitative methods showed excellent discrimination between LBD and non-LBD patients in each region assessed, using both SBRs and z-scores. Full Article
meth Interim PET evaluation in diffuse large B-cell lymphoma employing published recommendations: Comparison of the Deauville 5-point scale and the {Delta}SUVmax method By jnm.snmjournals.org Published On :: 2020-05-08T13:18:58-07:00 The value of interim 18F-fluorodeoxyglucose positron emission tomography (iPET) guided treatment decisions in patients with diffuse large B-cell lymphoma (DLBCL) has been the subject of much debate. This investigation focuses on a comparison of the Deauville score and the deltaSUVmax (SUVmax) approach – two methods to assess early metabolic response to standard chemotherapy in DLBCL. Methods: Of 609 DLBCL patients participating in the Positron Emission Tomography-guided Therapy of Aggressive non-Hodgkin Lymphomas (PETAL) trial, iPET scans of 596 patients originally evaluated using the SUVmax method were available for post-hoc assessment of the Deauville score. A commonly used definition of an unfavorable iPET result according to the Deauville score is an uptake greater than that of the liver, whereas an unfavorable iPET scan with regard to the SUVmax approach is characterized as a relative reduction of the maximum standardized uptake value between baseline and iPET staging of less than or equal to 66%. We investigated the two methods’ correlation and concordance by Spearman’s rank correlation coefficient and the agreement in classification, respectively. We further used Kaplan-Meier curves and Cox regression to assess differences in survival between patient subgroups defined by the pre-specified cut-offs. Time-dependent receiver operating curve analysis provided information on the methods’ respective discrimination performance. Results: Deauville score and SUVmax approach differed in their iPET-based prognosis. The SUVmax approach outperformed the Deauville score in terms of discrimination performance – most likely due to a high number of false-positive decisions by the Deauville score. Cut-off-independent discrimination performance remained low for both methods, but cut-off-related analyses showed promising results. Both favored the SUVmax approach, e.g. for the segregation by iPET response, where the event-free survival hazard ratio was 3.14 (95% confidence interval (CI): 2.22 – 4.46) for SUVmax and 1.70 (95% CI: 1.29 – 2.24) for the Deauville score. Conclusion: When considering treatment intensification, the currently used Deauville score cut-off of an uptake above that of the liver seems to be inappropriate and associated with potential harm for DLBCL patients. The SUVmax criterion of a relative reduction of the maximum standardized uptake value of less than or equal to 66% should be considered as an alternative. Full Article
meth Development of a sensitive and quantitative method for the identification of two major furan fatty acids in human plasma By feedproxy.google.com Published On :: 2020-04-01 Long XuApr 1, 2020; 61:560-569Methods Full Article
meth A simple method for sphingolipid analysis of tissues embedded in optimal cutting temperature compound By feedproxy.google.com Published On :: 2020-04-27 Timothy D RohrbachApr 27, 2020; 0:jlr.D120000809v1-jlr.D120000809Methods Full Article
meth An LC/MS/MS method for analyzing the steroid metabolome with high accuracy and from small serum samples By feedproxy.google.com Published On :: 2020-04-01 Teng-Fei YuanApr 1, 2020; 61:580-586Methods Full Article
meth Serum non-esterified fatty acids have utility as dietary biomarkers of fat intake from fish, fish oil and dairy in women [Methods] By feedproxy.google.com Published On :: 2020-03-31T09:30:24-07:00 Nutritional studies rely on various biological specimens for fatty acid (FA) determination, yet it is unclear how levels of serum non-esterified FA (NEFAs) correlate with other circulating lipid pools. Here, we used a high throughput method (< 4 min/sample) based on multisegment injection-non-aqueous-capillary electrophoresis–mass spectrometry (MSI-NACE-MS) to investigate whether specific serum NEFAs have utility as biomarkers of dietary fat intake in women. We first identified circulating NEFAs correlated with long-term/habitual food intake among pregnant women with contrasting dietary patterns (n=50). Acute changes in serum NEFA trajectories were also studied in non-pregnant women (n=18) following high-dose (5 g/day) fish oil (FO) supplementation or isoenergetic sunflower oil placebo over 56 days. In the cross-sectional study, serum omega-3 (-3) FA correlated with self-reported total -3 daily intake, notably eicosapentaenoic acid (EPA) as its NEFA (r=0.46; p=0.001), whereas pentadecanoic acid was associated with full-fat dairy intake (r=0.43; p=0.002), outcomes consistent with results from total FA serum hydrolysates. In the intervention cohort, serum -3 NEFAs increased 2.5-fold from baseline within 28 days following FO supplementation, and this increase was most pronounced for EPA (p=0.0004). Unlike for docosahexaenoic acid, circulating EPA as its NEFA also strongly correlated to EPA concentrations measured from erythrocyte phospholipid hydrolysates (r=0.66; p=4.6 x 10-10), and was better suited to detect dietary non-adherence. We conclude that MSI-NACE-MS offers a rapid method to quantify serum NEFAs and objectively monitor dietary fat intake in women that is complementary to diet records or food frequency questionnaires. Full Article