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  1. Book ; Online: Imaging of PbWO4 Crystals for G Experiment Test Masses Using a Laser Interferometer

    Assumin-Gyimah, K. T. A. / Holt, M. G. / Dutta, D. / Snow, W. M.

    2022  

    Abstract: It is highly desirable for future measurements of Newton's gravitational constant $G$ to use test ... for the critical distance measurements often needed in a $G$ apparatus. We present an upper bound on possible ... of magnitude smaller than what is required for $G$ measurements. They are also consistent with but more ...

    Abstract It is highly desirable for future measurements of Newton's gravitational constant $G$ to use test/source masses that allow nondestructive, quantitative internal density gradient measurements. High density optically transparent materials are ideally suited for this purpose since their density gradient can be measured with laser interferometry, and they allow in-situ optical metrology methods for the critical distance measurements often needed in a $G$ apparatus. We present an upper bound on possible internal density gradients in lead tungstate (PbWO$_4$) crystals determined using a laser interferometer. We placed an upper bound on the fractional atomic density gradient in two PbWO$_4$ test crystals of ${1 \over \rho}{d\rho \over dx}<2.1 \times 10^{-8}$ cm$^{-1}$. This value is more than two orders of magnitude smaller than what is required for $G$ measurements. They are also consistent with but more sensitive than a recently reported measurements of the same samples, using neutron interferometry. These results indicate that PbWO$_4$ crystals are well suited to be used as test masses in $G$ experiments. Future measurements of internal density gradients of test masses used for measurements of $G$ can now be conducted non-destructively for a wide range of possible test masses.

    Comment: 8 pages, 5 figures, submitted to Classical and Quantum Gravity. arXiv admin note: substantial text overlap with arXiv:2109.14008
    Keywords Physics - Instrumentation and Detectors ; General Relativity and Quantum Cosmology ; Nuclear Experiment
    Subject code 621
    Publishing date 2022-04-26
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article: Dental Society of Western New York: Retiring Address of the President, R. G. Snow.

    Snow, R G

    The Dental register

    2021  Volume 21, Issue 11, Page(s) 457–475

    Language English
    Publishing date 2021-03-10
    Publishing country United States
    Document type Journal Article
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Differential methylation of G-protein coupled receptor signaling genes in gastrointestinal neuroendocrine tumors.

    Byun, Seyoun / Affolter, Kajsa E / Snow, Angela K / Curtin, Karen / Cannon, Austin R / Cannon-Albright, Lisa A / Thota, Ramya / Neklason, Deborah W

    Scientific reports

    2021  Volume 11, Issue 1, Page(s) 12303

    Abstract: ... Genes from the G-protein coupled receptor (GPCR) pathways are statistically overrepresented ...

    Abstract Neuroendocrine tumors (NETs) of the small intestine undergo large chromosomal and methylation changes. The objective of this study was to identify methylation differences in NETs and consider how the differentially methylated genes may impact patient survival. Genome-wide methylation and chromosomal copy number variation (CNV) of NETs from the small intestine and appendix were measured. Tumors were divided into three molecular subtypes according to CNV results: chromosome 18 loss (18LOH), Multiple CNV, and No CNV. Comparison of 18LOH tumors with MultiCNV and NoCNV tumors identified 901 differentially methylated genes. Genes from the G-protein coupled receptor (GPCR) pathways are statistically overrepresented in the differentially methylated genes. One of the highlighted genes from the GPCR pathway is somatostatin (SST), a clinical target for NETs. Patient survival based on low versus high methylation in all samples identified four significant genes (p < 0.05) OR2S2, SMILR, RNU6-653P, and AC010543.1. Within the 18LOH molecular subtype tumors, survival differences were identified in high versus low methylation of 24 genes. The most significant is TRHR (p < 0.01), a GPCR with multiple FDA-approved drugs. By separating NETs into different molecular subtypes based on chromosomal changes, we find that multiple GPCRs and their ligands appear to be regulated through methylation and correlated with survival. These results suggest opportunities for better treatment strategies for NETs based on molecular features.
    MeSH term(s) Adult ; Aged ; Aged, 80 and over ; DNA Copy Number Variations/genetics ; DNA Methylation/genetics ; Disease-Free Survival ; Female ; Gastrointestinal Neoplasms/genetics ; Gastrointestinal Neoplasms/pathology ; Gene Expression Regulation, Neoplastic/genetics ; Genome, Human/genetics ; Humans ; Intestine, Small/metabolism ; Intestine, Small/pathology ; Male ; Middle Aged ; Neoplasm Proteins/genetics ; Neuroendocrine Tumors/genetics ; Neuroendocrine Tumors/pathology ; Receptors, G-Protein-Coupled/genetics ; Signal Transduction/genetics
    Chemical Substances Neoplasm Proteins ; Receptors, G-Protein-Coupled
    Language English
    Publishing date 2021-06-10
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-021-91934-5
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Book ; Online: Neutron Phase Contrast Imaging of PbWO$_{4}$ Crystals for G Experiment Test Masses Using a Talbot-Lau Neutron Interferometer

    Assumin-Gyimah, K. T. A. / Dutta, D. / Hussey, D. S. / Snow, W. M. / Langlois, C. / Lee, V.

    2021  

    Abstract: ... constant $G$. Such transparent test mass materials can enable nondestructive, quantitative internal ... realized for the critical distance measurements often needed in a $G$ apparatus. To confirm the sensitivity ... of magnitude smaller than required for $G$ measurements. We discuss the implications of this result and ...

    Abstract The use of transparent test/source masses can benefit future measurements of Newton's gravitational constant $G$. Such transparent test mass materials can enable nondestructive, quantitative internal density gradient measurements using optical interferometry and allow in-situ optical metrology methods to be realized for the critical distance measurements often needed in a $G$ apparatus. To confirm the sensitivity of such optical interferometry measurements to internal density gradients it is desirable to conduct a check with a totally independent technique. We present an upper bound on possible internal density gradients in lead tungstate (PbWO$_4$) crystals using a Talbot-Lau neutron interferometer on the Cold Neutron Imaging Facility (CNIF) at NIST. We placed an upper bound on a fractional atomic density gradient in two PbWO$_{4}$ test crystals of ${1 \over N}{dN \over dx}<0.5 \times 10^{-6}$ cm$^{-1}$. This value is about two orders of magnitude smaller than required for $G$ measurements. We discuss the implications of this result and of other nondestructive methods for characterization of internal density inhomogeneties which can be applied to test masses in $G$ experiments.

    Comment: 10 pages, 8 figures, submitted to Classical and Quantum Gravity
    Keywords Physics - Instrumentation and Detectors ; Condensed Matter - Materials Science ; General Relativity and Quantum Cosmology ; Nuclear Experiment
    Publishing date 2021-09-26
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: Differential methylation of G-protein coupled receptor signaling genes in gastrointestinal neuroendocrine tumors

    Seyoun Byun / Kajsa E. Affolter / Angela K. Snow / Karen Curtin / Austin R. Cannon / Lisa A. Cannon-Albright / Ramya Thota / Deborah W. Neklason

    Scientific Reports, Vol 11, Iss 1, Pp 1-

    2021  Volume 11

    Abstract: ... differentially methylated genes. Genes from the G-protein coupled receptor (GPCR) pathways are statistically ...

    Abstract Abstract Neuroendocrine tumors (NETs) of the small intestine undergo large chromosomal and methylation changes. The objective of this study was to identify methylation differences in NETs and consider how the differentially methylated genes may impact patient survival. Genome-wide methylation and chromosomal copy number variation (CNV) of NETs from the small intestine and appendix were measured. Tumors were divided into three molecular subtypes according to CNV results: chromosome 18 loss (18LOH), Multiple CNV, and No CNV. Comparison of 18LOH tumors with MultiCNV and NoCNV tumors identified 901 differentially methylated genes. Genes from the G-protein coupled receptor (GPCR) pathways are statistically overrepresented in the differentially methylated genes. One of the highlighted genes from the GPCR pathway is somatostatin (SST), a clinical target for NETs. Patient survival based on low versus high methylation in all samples identified four significant genes (p < 0.05) OR2S2, SMILR, RNU6-653P, and AC010543.1. Within the 18LOH molecular subtype tumors, survival differences were identified in high versus low methylation of 24 genes. The most significant is TRHR (p < 0.01), a GPCR with multiple FDA-approved drugs. By separating NETs into different molecular subtypes based on chromosomal changes, we find that multiple GPCRs and their ligands appear to be regulated through methylation and correlated with survival. These results suggest opportunities for better treatment strategies for NETs based on molecular features.
    Keywords Medicine ; R ; Science ; Q
    Subject code 570
    Language English
    Publishing date 2021-06-01T00:00:00Z
    Publisher Nature Portfolio
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: Conantokin-G attenuates detrimental effects of NMDAR hyperactivity in an ischemic rat model of stroke.

    Balsara, Rashna / Dang, Alexander / Donahue, Deborah L / Snow, Tiffany / Castellino, Francis J

    PloS one

    2015  Volume 10, Issue 3, Page(s) e0122840

    Abstract: The neuroprotective activity of conantokin-G (con-G), a naturally occurring antagonist of N-methyl ... regions served as robust internal controls. Intrathecal injection of con-G, post-middle carotid artery ... and significant recovery of neurological deficits was observed at 26 hr. Administration of con-G ...

    Abstract The neuroprotective activity of conantokin-G (con-G), a naturally occurring antagonist of N-methyl-D-aspartate receptors (NMDAR), was neurologically and histologically compared in the core and peri-infarct regions after ischemia/reperfusion brain injury in male Sprague-Dawley rats. The contralateral regions served as robust internal controls. Intrathecal injection of con-G, post-middle carotid artery occlusion (MCAO), caused a dramatic decrease in brain infarct size and swelling at 4 hr, compared to 26 hr, and significant recovery of neurological deficits was observed at 26 hr. Administration of con-G facilitated neuronal recovery in the peri-infarct regions as observed by decreased neurodegeneration and diminished calcium microdeposits at 4 hr and 26 hr. Intact Microtubule Associated Protein (MAP2) staining and neuronal cytoarchitecture was observed in the peri-infarct regions of con-G treated rats at both timepoints. Con-G restored localization of GluN1 and GluN2B subunits in the neuronal soma, but not that of GluN2A, which was perinuclear in the peri-infarct regions at 4 hr and 26 hr. This suggests that molecular targeting of the GluN2B subunit has potential for reducing detrimental consequences of ischemia. Overall, the data demonstrated that stroke-induced NMDAR excitoxicity is ameliorated by con-G-mediated repair of neurological and neuroarchitectural deficits, as well as by reconstituting neuronal localization of GluN1 and GluN2B subunits in the peri-infarct region of the stroked brain.
    MeSH term(s) Animals ; Brain/drug effects ; Brain/metabolism ; Brain/pathology ; Brain Infarction/complications ; Brain Infarction/drug therapy ; Brain Infarction/metabolism ; Brain Infarction/pathology ; Conotoxins/pharmacology ; Conotoxins/therapeutic use ; Disease Models, Animal ; Male ; Microtubule-Associated Proteins/metabolism ; Neurons/drug effects ; Neurons/metabolism ; Neuroprotective Agents/pharmacology ; Neuroprotective Agents/therapeutic use ; Protein Subunits/metabolism ; Protein Transport/drug effects ; Rats ; Rats, Sprague-Dawley ; Receptors, N-Methyl-D-Aspartate/metabolism ; Reperfusion Injury/complications ; Time Factors ; Treatment Outcome
    Chemical Substances Conotoxins ; MAP2 protein, rat ; Microtubule-Associated Proteins ; NR2B NMDA receptor ; Neuroprotective Agents ; Protein Subunits ; Receptors, N-Methyl-D-Aspartate ; conotoxin GV (93438-65-4)
    Language English
    Publishing date 2015-03-30
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ISSN 1932-6203
    ISSN (online) 1932-6203
    DOI 10.1371/journal.pone.0122840
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Conantokin-G attenuates detrimental effects of NMDAR hyperactivity in an ischemic rat model of stroke.

    Rashna Balsara / Alexander Dang / Deborah L Donahue / Tiffany Snow / Francis J Castellino

    PLoS ONE, Vol 10, Iss 3, p e

    2015  Volume 0122840

    Abstract: The neuroprotective activity of conantokin-G (con-G), a naturally occurring antagonist of N-methyl ... regions served as robust internal controls. Intrathecal injection of con-G, post-middle carotid artery ... and significant recovery of neurological deficits was observed at 26 hr. Administration of con-G ...

    Abstract The neuroprotective activity of conantokin-G (con-G), a naturally occurring antagonist of N-methyl-D-aspartate receptors (NMDAR), was neurologically and histologically compared in the core and peri-infarct regions after ischemia/reperfusion brain injury in male Sprague-Dawley rats. The contralateral regions served as robust internal controls. Intrathecal injection of con-G, post-middle carotid artery occlusion (MCAO), caused a dramatic decrease in brain infarct size and swelling at 4 hr, compared to 26 hr, and significant recovery of neurological deficits was observed at 26 hr. Administration of con-G facilitated neuronal recovery in the peri-infarct regions as observed by decreased neurodegeneration and diminished calcium microdeposits at 4 hr and 26 hr. Intact Microtubule Associated Protein (MAP2) staining and neuronal cytoarchitecture was observed in the peri-infarct regions of con-G treated rats at both timepoints. Con-G restored localization of GluN1 and GluN2B subunits in the neuronal soma, but not that of GluN2A, which was perinuclear in the peri-infarct regions at 4 hr and 26 hr. This suggests that molecular targeting of the GluN2B subunit has potential for reducing detrimental consequences of ischemia. Overall, the data demonstrated that stroke-induced NMDAR excitoxicity is ameliorated by con-G-mediated repair of neurological and neuroarchitectural deficits, as well as by reconstituting neuronal localization of GluN1 and GluN2B subunits in the peri-infarct region of the stroked brain.
    Keywords Medicine ; R ; Science ; Q
    Language English
    Publishing date 2015-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article: Assays of complex formation between RGS protein G gamma subunit-like domains and G beta subunits.

    Siderovski, David P / Snow, Bryan E / Chung, Stephen / Brothers, Greg M / Sondek, John / Betts, Laurie

    Methods in enzymology

    2002  Volume 344, Page(s) 702–723

    MeSH term(s) Amino Acid Sequence ; Animals ; Baculoviridae/genetics ; Base Sequence ; Cell Line ; DNA Primers ; Electrophoresis, Polyacrylamide Gel/methods ; Heterotrimeric GTP-Binding Proteins/chemistry ; Heterotrimeric GTP-Binding Proteins/genetics ; Heterotrimeric GTP-Binding Proteins/metabolism ; Insecta ; Mice ; Molecular Sequence Data ; Polymerase Chain Reaction/methods ; Protein Subunits ; RGS Proteins/chemistry ; RGS Proteins/genetics ; RGS Proteins/metabolism ; Recombinant Proteins/chemistry ; Recombinant Proteins/metabolism ; Signal Transduction ; Transfection/methods
    Chemical Substances DNA Primers ; Protein Subunits ; RGS Proteins ; Recombinant Proteins ; Heterotrimeric GTP-Binding Proteins (EC 3.6.5.1)
    Language English
    Publishing date 2002
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S.
    ISSN 0076-6879
    ISSN 0076-6879
    DOI 10.1016/s0076-6879(02)44750-7
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: Dynamic regulation of RGS2 suggests a novel mechanism in G-protein signaling and neuronal plasticity.

    Ingi, T / Krumins, A M / Chidiac, P / Brothers, G M / Chung, S / Snow, B E / Barnes, C A / Lanahan, A A / Siderovski, D P / Ross, E M / Gilman, A G / Worley, P F

    The Journal of neuroscience : the official journal of the Society for Neuroscience

    1998  Volume 18, Issue 18, Page(s) 7178–7188

    Abstract: ... we demonstrate that mRNA encoding a member of the regulator of G-protein signaling (RGS) family, RGS2, is rapidly ...

    Abstract Long-term neuronal plasticity is known to be dependent on rapid de novo synthesis of mRNA and protein, and recent studies provide insight into the molecules involved in this response. Here, we demonstrate that mRNA encoding a member of the regulator of G-protein signaling (RGS) family, RGS2, is rapidly induced in neurons of the hippocampus, cortex, and striatum in response to stimuli that evoke plasticity. Although several members of the RGS family are expressed in brain with discrete neuronal localizations, RGS2 appears unique in that its expression is dynamically responsive to neuronal activity. In biochemical assays, RGS2 stimulates the GTPase activity of the alpha subunit of Gq and Gi1. The effect on Gi1 was observed only after reconstitution of the protein in phospholipid vesicles containing M2 muscarinic acetylcholine receptors. RGS2 also inhibits both Gq- and Gi-dependent responses in transfected cells. These studies suggest a novel mechanism linking neuronal activity and signal transduction.
    MeSH term(s) Animals ; COS Cells/chemistry ; COS Cells/enzymology ; Calcium-Calmodulin-Dependent Protein Kinases/metabolism ; Cerebral Cortex/chemistry ; Cerebral Cortex/cytology ; Cerebral Cortex/enzymology ; Cocaine/pharmacology ; Dopamine Antagonists/pharmacology ; Dopamine Uptake Inhibitors/pharmacology ; Female ; GTP Phosphohydrolases/metabolism ; GTP-Binding Proteins/physiology ; Gene Expression/drug effects ; Gene Expression/physiology ; Genes, Immediate-Early/physiology ; Haloperidol/pharmacology ; Hippocampus/chemistry ; Hippocampus/cytology ; Hippocampus/enzymology ; Hydrolysis ; Lipid Metabolism ; Male ; Neuronal Plasticity/physiology ; Neurons/chemistry ; Neurons/drug effects ; Neurons/enzymology ; RNA, Messenger/metabolism ; Rats ; Rats, Inbred F344 ; Rats, Sprague-Dawley ; Receptors, Muscarinic/physiology ; Signal Transduction/drug effects ; Signal Transduction/physiology ; Synaptic Transmission/drug effects ; Synaptic Transmission/physiology
    Chemical Substances Dopamine Antagonists ; Dopamine Uptake Inhibitors ; RNA, Messenger ; Receptors, Muscarinic ; Calcium-Calmodulin-Dependent Protein Kinases (EC 2.7.11.17) ; GTP Phosphohydrolases (EC 3.6.1.-) ; GTP-Binding Proteins (EC 3.6.1.-) ; Cocaine (I5Y540LHVR) ; Haloperidol (J6292F8L3D)
    Language English
    Publishing date 1998-09-15
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 604637-x
    ISSN 1529-2401 ; 0270-6474
    ISSN (online) 1529-2401
    ISSN 0270-6474
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: A G protein gamma subunit-like domain shared between RGS11 and other RGS proteins specifies binding to Gbeta5 subunits.

    Snow, B E / Krumins, A M / Brothers, G M / Lee, S F / Wall, M A / Chung, S / Mangion, J / Arya, S / Gilman, A G / Siderovski, D P

    Proceedings of the National Academy of Sciences of the United States of America

    1998  Volume 95, Issue 22, Page(s) 13307–13312

    Abstract: Regulators of G protein signaling (RGS) proteins act as GTPase-activating proteins (GAPs ... toward the alpha subunits of heterotrimeric, signal-transducing G proteins. RGS11 contains a G protein gamma ... form complexes with specific Gbeta subunits, adding to the combinatorial complexity of G protein ...

    Abstract Regulators of G protein signaling (RGS) proteins act as GTPase-activating proteins (GAPs) toward the alpha subunits of heterotrimeric, signal-transducing G proteins. RGS11 contains a G protein gamma subunit-like (GGL) domain between its Dishevelled/Egl-10/Pleckstrin and RGS domains. GGL domains are also found in RGS6, RGS7, RGS9, and the Caenorhabditis elegans protein EGL-10. Coexpression of RGS11 with different Gbeta subunits reveals specific interaction between RGS11 and Gbeta5. The expression of mRNA for RGS11 and Gbeta5 in human tissues overlaps. The Gbeta5/RGS11 heterodimer acts as a GAP on Galphao, apparently selectively. RGS proteins that contain GGL domains appear to act as GAPs for Galpha proteins and form complexes with specific Gbeta subunits, adding to the combinatorial complexity of G protein-mediated signaling pathways.
    MeSH term(s) Amino Acid Sequence ; Animals ; Binding Sites ; Brain/metabolism ; COS Cells ; Caenorhabditis elegans ; Cattle ; Consensus Sequence ; Conserved Sequence ; GTP-Binding Proteins/chemistry ; GTP-Binding Proteins/genetics ; GTP-Binding Proteins/metabolism ; GTPase-Activating Proteins ; Humans ; Macromolecular Substances ; Mice ; Molecular Sequence Data ; Organ Specificity ; Protein Binding ; Protein Biosynthesis ; Proteins/chemistry ; Proteins/metabolism ; RNA, Messenger/biosynthesis ; Rats ; Recombinant Proteins/chemistry ; Recombinant Proteins/metabolism ; Retina/metabolism ; Sequence Alignment ; Sequence Homology, Amino Acid ; Spodoptera ; Transcription, Genetic ; Transfection
    Chemical Substances GTPase-Activating Proteins ; Macromolecular Substances ; Proteins ; RNA, Messenger ; Recombinant Proteins ; GTP-Binding Proteins (EC 3.6.1.-)
    Language English
    Publishing date 1998-10-27
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.95.22.13307
    Database MEDical Literature Analysis and Retrieval System OnLINE

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