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Raitt DC, Johnson AL, Erkine AM, Makino K, Morgan B, Gross DS, Johnston LH. The Skn7 response regulator of Saccharomyces cerevisiae interacts with Hsf1 in vivo and is required for the induction of heat shock genes by oxidative stress. Mol Biol Cell 2000; 11:2335-47. [PMID: 10888672 PMCID: PMC14923 DOI: 10.1091/mbc.11.7.2335] [Citation(s) in RCA: 131] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The Skn7 response regulator has previously been shown to play a role in the induction of stress-responsive genes in yeast, e.g., in the induction of the thioredoxin gene in response to hydrogen peroxide. The yeast Heat Shock Factor, Hsf1, is central to the induction of another set of stress-inducible genes, namely the heat shock genes. These two regulatory trans-activators, Hsf1 and Skn7, share certain structural homologies, particularly in their DNA-binding domains and the presence of adjacent regions of coiled-coil structure, which are known to mediate protein-protein interactions. Here, we provide evidence that Hsf1 and Skn7 interact in vitro and in vivo and we show that Skn7 can bind to the same regulatory sequences as Hsf1, namely heat shock elements. Furthermore, we demonstrate that a strain deleted for the SKN7 gene and containing a temperature-sensitive mutation in Hsf1 is hypersensitive to oxidative stress. Our data suggest that Skn7 and Hsf1 cooperate to achieve maximal induction of heat shock genes in response specifically to oxidative stress. We further show that, like Hsf1, Skn7 can interact with itself and is localized to the nucleus under normal growth conditions as well as during oxidative stress.
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Morgan B, McGill WJ. Benzothiazole-accelerated sulfur vulcanization. III. 2-Bisbenzothiazole-2,2?-disulfide as accelerator for 2,3-dimethyl-2-butene. J Appl Polym Sci 2000. [DOI: 10.1002/(sici)1097-4628(20000531)76:9<1395::aid-app4>3.0.co;2-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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128
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Morgan B, McGill WJ. Benzothiazole-accelerated sulfur vulcanization. II. 2-Mercaptobenzothiazole/zinc oxide and bis(2-mercaptobenzothiazole)zinc(II) as accelerators for 2,3-dimethyl-2-butene. J Appl Polym Sci 2000. [DOI: 10.1002/(sici)1097-4628(20000531)76:9<1386::aid-app3>3.0.co;2-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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129
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Morgan B, McGill WJ. Benzothiazole-accelerated sulfur vulcanization. IV. Effect of ZnO and bis(2-mercaptobenzothiazole)zinc(II) on 2-bisbenzothiazole-2,2?-polysulfide formation in 2-bisbenzothiazole-2,2?-disulfide and 2-bisbenzothiazole-2,2-disulfide/sulfur. J Appl Polym Sci 2000. [DOI: 10.1002/(sici)1097-4628(20000531)76:9<1405::aid-app5>3.0.co;2-b] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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130
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Morgan B, McGill WJ. Benzothiazole-accelerated sulfur vulcanization. V. 2-Bisbenzothiazole-2,2?-disulfide/ZnO and 2-bisbenzothiazole-2,2?-disulfide/ (2-mercaptobenzothiazole)zinc(II) as accelerators for 2,3-dimethyl-2-butene. J Appl Polym Sci 2000. [DOI: 10.1002/(sici)1097-4628(20000531)76:9<1413::aid-app6>3.0.co;2-d] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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131
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Sensky PR, Jivan A, Hudson NM, Keal RP, Morgan B, Tranter JL, de Bono D, Samani NJ, Cherryman GR. Coronary artery disease: combined stress MR imaging protocol-one-stop evaluation of myocardial perfusion and function. Radiology 2000; 215:608-14. [PMID: 10796946 DOI: 10.1148/radiology.215.2.r00ap12608] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The authors developed and tested a dual stress magnetic resonance (MR) imaging protocol to evaluate myocardial perfusion, function, and hibernation. The technique was well tolerated, and high-quality images were achieved. The comprehensive information obtained can be used to guide clinical management decisions regarding coronary artery revascularization procedures. This protocol offers a one-stop assessment of patients with coronary artery disease with use of a clinical MR imager.
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132
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Rueter JK, Mattern RH, Zhang L, Taylor J, Morgan B, Hoyer D, Goodman M. Syntheses and biological activities of sandostatin analogs containing stereochemical changes in positions 6 or 8. Biopolymers 2000; 53:497-505. [PMID: 10775065 DOI: 10.1002/(sici)1097-0282(200005)53:6<497::aid-bip6>3.0.co;2-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In a continuation of our research efforts on the design and synthesis of novel peptidomimetic structures, we have synthesized a series of sandostatin amide analogs in which stereoisomers of threonine and beta-hydroxyvaline(beta-Hyv) are employed. The analogs D-Phe1-c[Cys2-Phe3-D-Trp4-Lys5-Xaa6-Cys 7]-Xbb8-NH2 (Xaa = allo-Thr, D-allo-Thr, D-beta-Hyv, beta-Hyv, D-Thr, and Xbb = Thr or Xaa = Thr and Xbb = allo-Thr, D-allo-Thr, beta-Hyv, D-Thr) explore the effects on biological activity of stereochemical modifications and beta-methylation at positions 6 or 8. By these modifications, we examine the role of the two residues in binding to somatostatin receptors. We describe the synthesis and biological activity of these analogs. In combination with the results of the conformational analysis, this study provides new insights into the structural requirements for the binding affinity of somatostatin amide analogs to somatostatin receptors [Mattern et al., Conformational analyses of sandostatin analogs containing stereochemical changes in positions 6 or 8].
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133
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Morgan B. Diagnose and be damned. Inquiry should be held into doctors involved in child abuse investigations. BMJ (CLINICAL RESEARCH ED.) 2000; 320:1004-5. [PMID: 10809550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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134
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Morgan B. "Correcting" bmj.com. What happened to the false allegation in bmj. com? BMJ (CLINICAL RESEARCH ED.) 2000; 320:1005. [PMID: 10753162 PMCID: PMC1117877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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135
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136
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Bredell H, Hunt G, Morgan B, Tiemessen CT, Martin DJ, Morris L. Identification of HIV type 1 intersubtype recombinants in South Africa using env and gag heteroduplex mobility assays. AIDS Res Hum Retroviruses 2000; 16:493-7. [PMID: 10772535 DOI: 10.1089/088922200309151] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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137
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Prevost GP, Pradines A, Viossat I, Brezak MC, Miquel K, Lonchampt MO, Kasprzyk P, Favre G, Pignol B, Le Breton C, Dong J, Morgan B. Inhibition of human tumor cell growth in vitro and in vivo by a specific inhibitor of human farnesyltransferase: BIM-46068. Int J Cancer 1999; 83:283-7. [PMID: 10471540 DOI: 10.1002/(sici)1097-0215(19991008)83:2<283::aid-ijc22>3.0.co;2-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Oncogenic mutations of the ras gene leading to constitutive activation of downstream effectors have been detected in a large spectrum of human cancers (pancreas, thyroid, colon and NSCLC). Membrane anchorage of Ras required for functional activity in signal transduction is facilitated by post-translational modifications resulting in covalent attachment of a farnesyl group to the cysteine in the C-terminal CAAX motif. This attachment is mediated by farnesyltransferase (FTase). Here, we report a novel series of potent FTase inhibitors, where the tetrapeptide CAAX motif has been modified by incorporation of a thiazolidine carboxylic acid moiety followed by reduction of the 1st and 2nd peptide bonds to a secondary and tertiary amine, respectively. The C-terminal carboxylate was converted to esters for improved cellular penetration. These compounds showed specific inhibition of purified human FTase enzyme, inhibition of proliferation in vitro in a large spectrum of human tumor cell lines and inhibition of growth of human tumor xenografts in athymic nude mice. In addition, in regard to a panel of cell lines, using the Compare analysis to determine the Pearson coefficient correlation, the anti-proliferative spectrum of BIM-46068 has been shown to be distinct from the profile of typical chemotherapeutic agents.
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Morgan B. Nurse heroes: a class act. Interview by Chris Hart. NURSING TIMES 1999; 95:12-3. [PMID: 10603858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
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139
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Kniazeva M, Chiang MF, Morgan B, Anduze AL, Zack DJ, Han M, Zhang K. A new locus for autosomal dominant stargardt-like disease maps to chromosome 4. Am J Hum Genet 1999; 64:1394-9. [PMID: 10205271 PMCID: PMC1377876 DOI: 10.1086/302377] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Stargardt disease (STGD) is the most common hereditary macular dystrophy and is characterized by decreased central vision, atrophy of the macula and underlying retinal-pigment epithelium, and frequent presence of prominent flecks in the posterior pole of the retina. STGD is most commonly inherited as an autosomal recessive trait, but many families have been described in which features of the disease are transmitted in an autosomal dominant manner. A recessive locus has been identified on chromosome 1p (STGD1), and dominant loci have been mapped to both chromosome 13q (STGD2) and chromosome 6q (STGD3). In this study, we describe a kindred with an autosomal dominant Stargardt-like phenotype. A genomewide search demonstrated linkage to a locus on chromosome 4p, with a maximum LOD score of 5.12 at a recombination fraction of.00, for marker D4S403. Analysis of extended haplotypes localized the disease gene to an approximately 12-cM interval between loci D4S1582 and D4S2397. Therefore, this kindred establishes a new dominant Stargardt-like locus, STGD4.
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140
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Gregory G, Das Gupta R, Morgan B, Bounds G. Polyvinylsiloxane dental bite registration material used to splint a composite graft of the nasal rim. Br J Oral Maxillofac Surg 1999; 37:139-41. [PMID: 10371322 DOI: 10.1054/bjom.1998.0094] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We describe the construction of a nostril splint made from heavy body silicone-based dental impression material. This bio-compatible material supported a large chondrocutaneous auricular graft during early healing. The splint immobilized and maintained the shape of the alar rim and was further used nightly during the expected period of wound contraction.
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Morgan B. Diagnosing serious child abuse. Death from Munchausen syndrome by proxy is overestimated. BMJ (CLINICAL RESEARCH ED.) 1999; 318:462-3. [PMID: 9974472 PMCID: PMC1114918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
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142
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143
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Morgan B. Feather formations. Curr Biol 1999; 9:R41. [PMID: 10021373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
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144
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Morgan B. Risky business. NURSING TIMES 1998; 94:40. [PMID: 9887838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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145
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Jacobson P, Sambandan T, Morgan B. Determination of the chirality of cysteines in somatostatin analogs. J Chromatogr A 1998. [DOI: 10.1016/s0021-9673(98)00289-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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146
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Hocart SJ, Jain R, Murphy WA, Taylor JE, Morgan B, Coy DH. Potent antagonists of somatostatin: synthesis and biology. J Med Chem 1998; 41:1146-54. [PMID: 9544214 DOI: 10.1021/jm970730q] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The search for synthetic analogues of somatostatin (SRIF) which exhibit selective affinities for the five known receptor subtypes (sst1-5) has generated a large number of potent agonist analogues. Many of these agonists display good subtype selectivities and affinities for the subtypes 2, 3, and 5, with very few selective for sst1 or sst4. Until the recent report by Bass and co-workers (Mol. Pharmacol. 1996, 50, 709-715; erratum, Mol. Pharmacol. 1997, 51, 170), no true antagonists had been discovered, let alone any displaying differential receptor subtype selectivity. In this present study, we explore the effect of this putative L5,D6 antagonist motif on various series of somatostatin agonist analogues, both linear and cyclic. It was found that many D5,L6 agonists could be converted into competitive antagonists by applying this motif, the most potent of which was H-Nal-cyclo[DCys-Pal-DTrp-Lys-Val-Cys]-Nal-NH2 (32). This antagonist was selective for hsst2 with an affinity of 75 nM and an IC50 of 15.1 nM against SRIF-14 in a rat in vitro antagonist bioassay. Receptor-selective somatostatin antagonists should provide valuable tools for characterizing the many important physiological functions of this neuropeptide.
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Hudson DA, Krige JE, Grobbelaar AO, Morgan B, Grover R. Melanoma of the face: the safety of narrow excision margins. SCANDINAVIAN JOURNAL OF PLASTIC AND RECONSTRUCTIVE SURGERY AND HAND SURGERY 1998; 32:97-104. [PMID: 9556824 DOI: 10.1080/02844319850158985] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Recent studies have shown that narrower excision margins may be safe, but the optimal or minimum margin for melanoma is unknown. Wide margins of excision are possible on the trunk and limbs, but functional and cosmetic constraints often limit the extent of excision on the face. A collaborative study from two continents (Cape Town, South Africa and Northwood, England) investigated the outcome of different excision margins of 106 patients with stage I melanoma of the face. The margin of excision was measured from the records of the pathological specimen. Thirty patients had margins of less than 1 cm, 64 had margins of between 1 and 2 cm, and 12 had margins greater than 2 cm. Primary apposition or flap closure was possible in 85 patients. Seven patients developed local recurrences and these were not influenced by the excision margin. This study supports the contention that the primary treatment of cutaneous melanoma on the face should be histologically confirmed complete excision, and that this can be achieved with margins of excision less than 1 cm. Local recurrence is not related to the margin of excision or to tumour thickness.
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148
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Gasque P, Jones J, Singhrao SK, Morgan B. Identification of an astrocyte cell population from human brain that expresses perforin, a cytotoxic protein implicated in immune defense. J Exp Med 1998; 187:451-60. [PMID: 9463395 PMCID: PMC2212151 DOI: 10.1084/jem.187.4.451] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/1997] [Revised: 12/01/1997] [Indexed: 02/06/2023] Open
Abstract
The brain is an immunoprivileged organ isolated from the peripheral immune system. However, it has been shown that resident cells, notably astrocytes and microglia, can express numerous innate immune molecules, providing the capacity to generate a local antipathogen system. Perforin is a cytolytic protein present in the granules of cytotoxic T lymphocytes and natural killer cells. Expression in cells other than those of the hemopoetic lineage has not been described. We report here that fetal astrocytes in culture (passages 2 to 15), astrocytoma, and adult astrocytes expressed perforin. Reverse transcriptase polymerase chain reaction followed by Southern blot was carried out using multiple specific primers and all cDNAs were cloned and sequenced. Human fetal astrocyte perforin cDNA sequence was approximately 100% identical to the reported perforin cDNA cloned from T cells. Western blot analysis using monoclonal and polyclonal antiperforin peptide antibodies revealed a protein of 65 kD in both human fetal astrocyte and rat natural killer cell lysates (n = 4). Immunostaining followed by FACS(R) and confocal and electron microscopy analysis revealed that perforin was expressed by 40-50% of glial fibrillary acidic protein positive cells present in the fetal brain culture (n = 11). Perforin was not localized to granules in astrocytes but was present throughout the cytoplasm, probably in association with the endoplasmic reticulum. Perforin was not detected in normal adult brain tissue but was present in and around areas of inflammation (white and grey matter) in multiple sclerosis and neurodegenerative brains. Perforin-positive cells were identified as reactive astrocytes. These findings demonstrate that perforin expression is not unique to lymphoid cells and suggest that perforin produced by a subpopulation of astrocytes plays a role in inflammation in the brain.
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149
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Louie T, Morgan B, Standiford HC. Facet and facet-joint infections: case report and review. Clin Infect Dis 1998; 26:510-2. [PMID: 9502488 DOI: 10.1086/517100] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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150
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Morgan B. Certification communiqué. OFFICIAL JOURNAL OF THE CANADIAN ASSOCIATION OF CRITICAL CARE NURSES 1998; 9:10-1. [PMID: 10347488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
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