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  1. Article ; Online: Zr(IV) Catalyst for the Ring-Opening Copolymerization of Anhydrides (A) with Epoxides (B), Oxetane (B), and Tetrahydrofurans (C) to Make ABB- and/or ABC-Poly(ester-

    Kerr, Ryan W F / Williams, Charlotte K

    Journal of the American Chemical Society

    2022  Volume 144, Issue 15, Page(s) 6882–6893

    Abstract: Poly(ester- ...

    Abstract Poly(ester-
    MeSH term(s) Anhydrides ; Catalysis ; Epoxy Compounds ; Esters ; Ethers ; Ethers, Cyclic ; Furans ; Kinetics ; Oxides ; Phthalic Anhydrides ; Polymerization ; Polymers
    Chemical Substances Anhydrides ; Epoxy Compounds ; Esters ; Ethers ; Ethers, Cyclic ; Furans ; Oxides ; Phthalic Anhydrides ; Polymers ; oxetane (I279Q16FU6)
    Language English
    Publishing date 2022-04-07
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 3155-0
    ISSN 1520-5126 ; 0002-7863
    ISSN (online) 1520-5126
    ISSN 0002-7863
    DOI 10.1021/jacs.2c01225
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: Zr(IV) Catalyst for the Ring-Opening Copolymerization of Anhydrides (A) with Epoxides (B), Oxetane (B), and Tetrahydrofurans (C) to Make ABB- and/or ABC-Poly(ester-alt-ethers)

    Kerr, Ryan W. F. / Williams, Charlotte K.

    Journal of the American Chemical Society. 2022 Apr. 07, v. 144, no. 15

    2022  

    Abstract: ... by two ring-opened cyclic ethers (B/C) (−ABB– or −ABC−). It operates with high polymerization control ... ethers) have lower glass-transition temperatures (−16 °C < Tg < 12 °C) than the analogous alternating ...

    Abstract Poly(ester-alt-ethers) can combine beneficial ether linkage flexibility and polarity with ester linkage hydrolysability, furnishing fully degradable polymers. Despite their promising properties, this class of polymers remains underexplored, in part due to difficulties in polymer synthesis. Here, a catalyzed copolymerization using commercially available monomers, butylene oxide (BO)/oxetane (OX), tetrahydrofuran (THF), and phthalic anhydride (PA), accesses a series of well-defined poly(ester-alt-ethers). A Zr(IV) catalyst is reported that yields polymer repeat units comprising a ring-opened PA (A), followed by two ring-opened cyclic ethers (B/C) (−ABB– or −ABC−). It operates with high polymerization control, good rate, and successfully enchains epoxides, oxetane, and/or tetrahydrofurans, providing a straightforward means to moderate the distance between ester linkages. Kinetic analysis of PA/BO copolymerization, with/without THF, reveals an overall second-order rate law: first order in both catalyst and butylene oxide concentrations but zero order in phthalic anhydride and, where it is present, zero order in THF. Poly(ester-alt-ethers) have lower glass-transition temperatures (−16 °C < Tg < 12 °C) than the analogous alternating polyesters, consistent with the greater backbone flexibility. They also show faster ester hydrolysis rates compared with the analogous AB polymers. The Zr(IV) catalyst furnishes poly(ester-alt-ethers) from a range of commercially available epoxides and anhydride; it presents a straightforward method to moderate degradable polymers’ properties.
    Keywords catalysts ; catalytic activity ; copolymerization ; epoxides ; glass transition ; hydrolysis ; kinetics ; phthalic anhydride ; tetrahydrofuran
    Language English
    Dates of publication 2022-0407
    Size p. 6882-6893.
    Publishing place American Chemical Society
    Document type Article
    ZDB-ID 3155-0
    ISSN 1520-5126 ; 0002-7863
    ISSN (online) 1520-5126
    ISSN 0002-7863
    DOI 10.1021/jacs.2c01225
    Database NAL-Catalogue (AGRICOLA)

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  3. Article: Prof. W. E. Agar, C.B.E., F.R.S.

    KERR, J G

    Nature

    2004  Volume 168, Issue 4273, Page(s) 494–495

    MeSH term(s) Agar ; History, 19th Century ; History, 20th Century ; Zoology
    Chemical Substances Agar (9002-18-0)
    Language English
    Publishing date 2004-01-12
    Publishing country England
    Document type Biography ; Historical Article ; Journal Article
    ZDB-ID 120714-3
    ISSN 1476-4687 ; 0028-0836
    ISSN (online) 1476-4687
    ISSN 0028-0836
    DOI 10.1038/168494a0
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: In vivo seizure induction and pharmacological preconditioning by domoic acid and isodomoic acids A, B and C.

    Sawant, P M / Holland, P T / Mountfort, D O / Kerr, D S

    Neuropharmacology

    2008  Volume 55, Issue 8, Page(s) 1412–1418

    Abstract: ... in mammals. Here we assessed the acute seizurogenic and toxic properties of DA, isodomoic acids A, B and C ... Iso-A, -B, -C), and the therapeutic potential of these compounds as pharmacological preconditioning ... agents. DA, Iso-A, Iso-B, and Iso-C all produced significant dose-dependent increases in seizure activity ...

    Abstract To date, nothing is known of the pharmacological properties of isomers of domoic acid (DA) in vivo in mammals. Here we assessed the acute seizurogenic and toxic properties of DA, isodomoic acids A, B and C (Iso-A, -B, -C), and the therapeutic potential of these compounds as pharmacological preconditioning agents. DA, Iso-A, Iso-B, and Iso-C all produced significant dose-dependent increases in seizure activity following intrahippocampal administration; doses producing half maximal cumulative seizure scores (ED50) were 137 pmol, 171 pmol, 13,000 pmol, and 3150 pmol, respectively. Pharmacological preconditioning with low-dose DA or Iso-A, 60 min before a high test dose of DA produced a significant reduction in seizure scores. In contrast, Iso-B and Iso-C each failed to induce any detectable tolerance to high-dose DA. Radioligand binding indicated a significant correlation between seizurogenic potency and kainate receptor affinity with KIs of 2.4 nM, 4.4 nM, 4990 nM and 170 nM for DA, Iso-A, Iso-B and Iso-C, respectively. Our in vivo results indicate that DA and Iso-A are functionally equipotent in acute seizure induction by direct intrahippocampal administration, while Iso-B and Iso-C are distinctly less potent.
    MeSH term(s) Animals ; Behavior, Animal/drug effects ; Disease Models, Animal ; Dose-Response Relationship, Drug ; Drug Tolerance ; Heptanoic Acids ; Hippocampus/drug effects ; Hippocampus/physiopathology ; Isomerism ; Kainic Acid/analogs & derivatives ; Kainic Acid/chemistry ; Kainic Acid/toxicity ; Male ; Marine Toxins/toxicity ; Protein Binding/drug effects ; Rats ; Rats, Sprague-Dawley ; Receptors, Kainic Acid/metabolism ; Seizures/chemically induced ; Seizures/prevention & control
    Chemical Substances Heptanoic Acids ; Marine Toxins ; Receptors, Kainic Acid ; isodomoic acid A ; isodomoic acid C ; domoic acid (M02525818H) ; Kainic Acid (SIV03811UC)
    Language English
    Publishing date 2008-12
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 218272-5
    ISSN 1873-7064 ; 0028-3908
    ISSN (online) 1873-7064
    ISSN 0028-3908
    DOI 10.1016/j.neuropharm.2008.09.001
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Metastasis-Associated Gene Expression Changes Predict Poor Outcomes in Patients with Dukes Stage B and C Colorectal Cancer.

    Jorissen, Robert N / Gibbs, Peter / Christie, Michael / Prakash, Saurabh / Lipton, Lara / Desai, Jayesh / Kerr, David / Aaltonen, Lauri A / Arango, Diego / Kruhøffer, Mogens / Orntoft, Torben F / Andersen, Claus Lindbjerg / Gruidl, Mike / Kamath, Vidya P / Eschrich, Steven / Yeatman, Timothy J / Sieber, Oliver M

    Clinical cancer research : an official journal of the American Association for Cancer Research

    2009  Volume 15, Issue 24, Page(s) 7642–7651

    Abstract: ... limited discrimination for Dukes stage B and C disease. Additional markers for outcome are required ... A and D tumors (three training sets) and assessed as a prognosis signature in stage B and C tumors ... expression changes between three sets of stage A and D cancers. Using consistent genes, stage B and C cancers ...

    Abstract PURPOSE: Colorectal cancer prognosis is currently predicted from pathologic staging, providing limited discrimination for Dukes stage B and C disease. Additional markers for outcome are required to help guide therapy selection for individual patients. EXPERIMENTAL DESIGN: A multisite single-platform microarray study was done on 553 colorectal cancers. Gene expression changes were identified between stage A and D tumors (three training sets) and assessed as a prognosis signature in stage B and C tumors (independent test and external validation sets). RESULTS: One hundred twenty-eight genes showed reproducible expression changes between three sets of stage A and D cancers. Using consistent genes, stage B and C cancers clustered into two groups resembling early-stage and metastatic tumors. A Prediction Analysis of Microarray algorithm was developed to classify individual intermediate-stage cancers into stage A-like/good prognosis or stage D-like/poor prognosis types. For stage B patients, the treatment adjusted hazard ratio for 6-year recurrence in individuals with stage D-like cancers was 10.3 (95% confidence interval, 1.3-80.0; P = 0.011). For stage C patients, the adjusted hazard ratio was 2.9 (95% confidence interval, 1.1-7.6; P = 0.016). Similar results were obtained for an external set of stage B and C patients. The prognosis signature was enriched for downregulated immune response genes and upregulated cell signaling and extracellular matrix genes. Accordingly, sparse tumor infiltration with mononuclear chronic inflammatory cells was associated with poor outcome in independent patients. CONCLUSIONS: Metastasis-associated gene expression changes can be used to refine traditional outcome prediction, providing a rational approach for tailoring treatments to subsets of patients. (Clin Cancer Res 2009;15(24):7642-51).
    Language English
    Publishing date 2009-12-08
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1225457-5
    ISSN 1557-3265 ; 1078-0432
    ISSN (online) 1557-3265
    ISSN 1078-0432
    DOI 10.1158/1078-0432.CCR-09-1431
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Stage-specific transcription of germline IgH C gamma and C alpha regions during human B cell differentiation.

    Kerr, W G / Burrows, P D

    International immunology

    1991  Volume 3, Issue 11, Page(s) 1059–1065

    Abstract: ... IgH) locus in human B lineage cells. Transcription of germline C gamma and C alpha was observed ... could not be detected in pre-B cells and only low levels of C alpha but not C gamma transcription were ... of the C gamma and C alpha regions may be a constitutive feature of the human B cell differentiation ...

    Abstract Previous studies have suggested that transcription of germline heavy chain constant region (CH) genes in murine B cells may determine the potential of their different CH regions to undergo isotype switch recombination. We have examined the transcriptional activity across the immunoglobulin heavy chain (IgH) locus in human B lineage cells. Transcription of germline C gamma and C alpha was observed in every surface IgM+ or surface IgM+/IgD+ B cell stage cell line and malignancy. In contrast, such transcription could not be detected in pre-B cells and only low levels of C alpha but not C gamma transcription were evident in IgM-secreting plasmablast cells. Transcriptional activity of germline IgH C epsilon was singularly absent at all stages of B cell development. Our results suggest that germline transcription of the C gamma and C alpha regions may be a constitutive feature of the human B cell differentiation program. Because this transcriptional activity is limited primarily to the B cell stage and occurs prior to the actual isotype switch, the induction of C gamma and C alpha transcription may represent preparation of the downstream IgH chromatin for potential switch recombination.
    MeSH term(s) B-Lymphocytes/cytology ; B-Lymphocytes/immunology ; Cell Differentiation ; Cell Line, Transformed ; Genes, Immunoglobulin ; Humans ; Immunoglobulin Constant Regions/genetics ; Immunoglobulin Switch Region ; Immunoglobulin alpha-Chains/genetics ; Immunoglobulin gamma-Chains/genetics ; Leukemia, Lymphocytic, Chronic, B-Cell/genetics ; Leukemia, Lymphocytic, Chronic, B-Cell/immunology ; Lymphoma, B-Cell/genetics ; Lymphoma, B-Cell/immunology ; Recombination, Genetic ; Transcription, Genetic
    Chemical Substances Immunoglobulin Constant Regions ; Immunoglobulin alpha-Chains ; Immunoglobulin gamma-Chains
    Language English
    Publishing date 1991-11
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 1013745-2
    ISSN 1460-2377 ; 0953-8178
    ISSN (online) 1460-2377
    ISSN 0953-8178
    DOI 10.1093/intimm/3.11.1059
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: I kappa B gamma, a 70 kd protein identical to the C-terminal half of p110 NF-kappa B: a new member of the I kappa B family.

    Inoue, J / Kerr, L D / Kakizuka, A / Verma, I M

    Cell

    1992  Volume 68, Issue 6, Page(s) 1109–1120

    Abstract: ... of the C-terminal region of 110 kd NF-kappa B protein. A 70 kd protein can be identified in lymphoid cells ... using antibodies raised against the C-terminal region of p110 NF-kappa B. Comparison of the two ... specific DNA binding of p50-p65 NF-kappa B heterodimer, p50 homodimer, and c-rel. p70 also interferes ...

    Abstract A cDNA corresponding to the 2.6 kb NF-kappa B mRNA species present in a variety of lymphoid cell lines has been molecularly cloned. The deduced 607 amino acid sequence is identical to the sequence of the C-terminal region of 110 kd NF-kappa B protein. A 70 kd protein can be identified in lymphoid cells using antibodies raised against the C-terminal region of p110 NF-kappa B. Comparison of the two-dimensional tryptic peptide maps of the 70 kd protein expressed in cells and the in vitro translated product encoded by the cDNA display extensive homology. The 70 kd protein expressed in bacteria prevents sequence-specific DNA binding of p50-p65 NF-kappa B heterodimer, p50 homodimer, and c-rel. p70 also interferes with transactivation by c-rel and prevents its nuclear translocation. The 70 kd protein, predominantly found in lymphoid cells, is a new member of the I kappa B family of proteins and is referred to as I kappa B gamma.
    MeSH term(s) Amino Acid Sequence ; Animals ; Base Sequence ; Cloning, Molecular ; Lymphocytes/metabolism ; Molecular Sequence Data ; Molecular Weight ; NF-kappa B/chemistry ; NF-kappa B/genetics ; NF-kappa B/isolation & purification ; Proto-Oncogene Proteins/metabolism ; Proto-Oncogene Proteins c-rel ; Transcription Factors/chemistry ; Transcription Factors/genetics
    Chemical Substances NF-kappa B ; Proto-Oncogene Proteins ; Proto-Oncogene Proteins c-rel ; Transcription Factors
    Language English
    Publishing date 1992-03-20
    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 187009-9
    ISSN 1097-4172 ; 0092-8674
    ISSN (online) 1097-4172
    ISSN 0092-8674
    DOI 10.1016/0092-8674(92)90082-n
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: c-rel activates but v-rel suppresses transcription from kappa B sites.

    Inoue, J / Kerr, L D / Ransone, L J / Bengal, E / Hunter, T / Verma, I M

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

    1991  Volume 88, Issue 9, Page(s) 3715–3719

    Abstract: We show that the product of the protooncogene c-rel is a constituent of an NF-kappa B-like complex ... gene. c-rel protein synthesized in bacteria binds to the kappa B site in a sequence-specific manner. The rel ... oligomers. The c-rel protein can activate transcription from promoters containing kappa B sites; v-rel ...

    Abstract We show that the product of the protooncogene c-rel is a constituent of an NF-kappa B-like complex that binds to the kappa B site originally identified in the enhancer of immunoglobulin kappa light chain gene. c-rel protein synthesized in bacteria binds to the kappa B site in a sequence-specific manner. The rel-kappa B complex can be disrupted by incubation with anti-rel antibodies. The rel protein can form oligomers. The c-rel protein can activate transcription from promoters containing kappa B sites; v-rel, on the other hand, suppresses the transcription of genes linked to kappa B sites. Thus, v-rel may interfere with the normal transcriptional machinery of the cell by acting as a dominant negative mutant.
    MeSH term(s) Amino Acid Sequence ; Animals ; Base Sequence ; Binding Sites ; Gene Expression Regulation ; In Vitro Techniques ; Mice ; Molecular Sequence Data ; NF-kappa B/physiology ; Oncogene Proteins v-rel ; Proto-Oncogene Proteins/physiology ; Proto-Oncogene Proteins c-rel ; Recombinant Proteins ; Regulatory Sequences, Nucleic Acid ; Repressor Proteins/physiology ; Retroviridae Proteins, Oncogenic/physiology ; Transcription Factors/physiology ; Transcription, Genetic
    Chemical Substances NF-kappa B ; Oncogene Proteins v-rel ; Proto-Oncogene Proteins ; Proto-Oncogene Proteins c-rel ; Recombinant Proteins ; Repressor Proteins ; Retroviridae Proteins, Oncogenic ; Transcription Factors
    Language English
    Publishing date 1991-05-01
    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.88.9.3715
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Choosing Wisely in a time of resource constraints.

    Born, Karen B / Levinson, Wendy / Pramesh, C S / Kerr, Eve A

    BMJ (Clinical research ed.)

    2024  Volume 385, Page(s) q166

    Language English
    Publishing date 2024-04-12
    Publishing country England
    Document type Editorial
    ZDB-ID 1362901-3
    ISSN 1756-1833 ; 0959-8154 ; 0959-8146 ; 0959-8138 ; 0959-535X ; 1759-2151
    ISSN (online) 1756-1833
    ISSN 0959-8154 ; 0959-8146 ; 0959-8138 ; 0959-535X ; 1759-2151
    DOI 10.1136/bmj.q166
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Cognitive mechanisms and resilience in UK-based general practitioners: cross-sectional findings.

    Kaleta, F O / Kristensen, C B / Duncan, M / Crutchley, P / Kerr, P / Hirsch, C R

    Occupational medicine (Oxford, England)

    2023  Volume 73, Issue 2, Page(s) 91–96

    Abstract: ... P < 0.01). In a hierarchical regression, positive interpretation bias (B = 0.25, SE B = 0.06, β = 0 ...

    Abstract Background: Being a general practitioner (GP) is a stressful occupation, and the strain GPs are under can have negative effects on their psychological well-being, as well as on the patients' experience of healthcare. Resilience can help buffer against this and is a dynamic process by which one can cope with adversity and stress.
    Aims: This study aimed to identify modifiable cognitive mechanisms related to resilience in GPs, specifically interpretation bias and cognitive reappraisal.
    Methods: One hundred and fourteen GPs completed an online cross-sectional correlational study. This comprised questionnaires assessing resilience, emotional distress, work environment and cognitive mechanisms (emotion regulation), as well as a task assessing interpretation bias.
    Results: Resilience of GPs was negatively correlated with measures of emotional distress. Furthermore, resilience was positively correlated with positive interpretation bias (r = 0.60, ρ = 0.60, P < 0.01) and cognitive reappraisal (r = 0.39, ρ = 0.40, P < 0.01). In a hierarchical regression, positive interpretation bias (B = 0.25, SE B = 0.06, β = 0.39, P < 0.01) was a significant independent predictor of resilience when controlling for depression, anxiety and stress.
    Conclusions: This is the first study to establish an association between resilience and positive interpretation bias and cognitive reappraisal in GPs. Future research should use longitudinal designs to determine if they have a causal role in promoting resilience, and importantly whether interventions focusing on these processes may foster resilience in less resilient GPs.
    MeSH term(s) Humans ; Resilience, Psychological ; General Practitioners ; Cross-Sectional Studies ; Cognition ; United Kingdom
    Language English
    Publishing date 2023-02-04
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1103950-4
    ISSN 1471-8405 ; 0962-7480
    ISSN (online) 1471-8405
    ISSN 0962-7480
    DOI 10.1093/occmed/kqad016
    Database MEDical Literature Analysis and Retrieval System OnLINE

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