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Dodson R, Manz KE, Burks SR, Gairola R, Lee NF, Liu Y, Pennell KD, Walker ED, Braun JM. Does Using Corsi-Rosenthal Boxes to Mitigate COVID-19 Transmission Also Reduce Indoor Air Concentrations of PFAS and Phthalates? Environ Sci Technol 2023; 57:415-427. [PMID: 36562547 PMCID: PMC9876422 DOI: 10.1021/acs.est.2c05169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The COVID-19 pandemic brought new emphasis on indoor air quality. However, few studies have investigated the impact of air filtration, a COVID-mitigation approach, on indoor air concentrations of semivolatile organic compounds (SVOCs). Using a quasi-experimental design, we quantified the impact of a relatively low-cost "do-it-yourself" air filter (Corsi-Rosenthal Box; CR Box) on indoor air concentrations of 42 PFAS and 24 other SVOCs. We sampled air before (October-November 2021) and during (February-March 2022) deployment of CR Boxes in 17 rooms located in an occupied Providence, Rhode Island office building. We measured sound levels in rooms with CR Boxes operating and not operating. While CR Boxes were deployed, concentrations of seven PFAS (N-EtFOSE, N-EtFOSA, FBSA, PFBS, PFHxS, PFOS, PFNA) were 28-61% lower and concentrations of five phthalates (DMP, DEP, DiBP, BBzP, DCHP) were 29-62% lower. Concentrations of five PFAS and one phthalate increased 23-44% during the intervention period, but the 95% CI of most of these estimates included the null. Daytime sound levels increased 5.0 dB when CR Boxes were operating. These results indicate that CR Boxes reduced exposure to several lower-volatility phthalates and sulfonated PFAS previously reported to be found in office building materials and products, with potentially distracting increases in sound levels.
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Affiliation(s)
- Robin
E. Dodson
- Silent
Spring Institute, Newton, Massachusetts02460, United States
| | - Katherine E. Manz
- School
of Engineering, Brown University, Providence, Rhode Island02912, United States
| | - Shaunessey R. Burks
- Department
of Epidemiology, Brown University, Providence, Rhode Island02912, United States
| | - Richa Gairola
- Department
of Epidemiology, Brown University, Providence, Rhode Island02912, United States
| | - Nina F. Lee
- Department
of Epidemiology, Brown University, Providence, Rhode Island02912, United States
| | - Yun Liu
- Department
of Epidemiology, Brown University, Providence, Rhode Island02912, United States
| | - Kurt D. Pennell
- School
of Engineering, Brown University, Providence, Rhode Island02912, United States
| | - Erica D. Walker
- Department
of Epidemiology, Brown University, Providence, Rhode Island02912, United States
| | - Joseph M. Braun
- Department
of Epidemiology, Brown University, Providence, Rhode Island02912, United States
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Bannister KW, Deller AT, Phillips C, Macquart JP, Prochaska JX, Tejos N, Ryder SD, Sadler EM, Shannon RM, Simha S, Day CK, McQuinn M, North-Hickey FO, Bhandari S, Arcus WR, Bennert VN, Burchett J, Bouwhuis M, Dodson R, Ekers RD, Farah W, Flynn C, James CW, Kerr M, Lenc E, Mahony EK, O'Meara J, Osłowski S, Qiu H, Treu T, U V, Bateman TJ, Bock DCJ, Bolton RJ, Brown A, Bunton JD, Chippendale AP, Cooray FR, Cornwell T, Gupta N, Hayman DB, Kesteven M, Koribalski BS, MacLeod A, McClure-Griffiths NM, Neuhold S, Norris RP, Pilawa MA, Qiao RY, Reynolds J, Roxby DN, Shimwell TW, Voronkov MA, Wilson CD. A single fast radio burst localized to a massive galaxy at cosmological distance. Science 2019; 365:565-570. [PMID: 31249136 DOI: 10.1126/science.aaw5903] [Citation(s) in RCA: 220] [Impact Index Per Article: 44.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 06/19/2019] [Indexed: 11/03/2022]
Abstract
Fast radio bursts (FRBs) are brief radio emissions from distant astronomical sources. Some are known to repeat, but most are single bursts. Nonrepeating FRB observations have had insufficient positional accuracy to localize them to an individual host galaxy. We report the interferometric localization of the single-pulse FRB 180924 to a position 4 kiloparsecs from the center of a luminous galaxy at redshift 0.3214. The burst has not been observed to repeat. The properties of the burst and its host are markedly different from those of the only other accurately localized FRB source. The integrated electron column density along the line of sight closely matches models of the intergalactic medium, indicating that some FRBs are clean probes of the baryonic component of the cosmic web.
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Affiliation(s)
- K W Bannister
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia.
| | - A T Deller
- Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, VIC 3122, Australia
| | - C Phillips
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - J-P Macquart
- International Centre for Radio Astronomy Research, Curtin University, Bentley, WA 6102, Australia
| | - J X Prochaska
- University of California Observatories-Lick Observatory, University of California, Santa Cruz, CA 95064, USA.,Kavli Institute for the Physics and Mathematics of the Universe, 5-1-5 Kashiwanoha, Kashiwa 277-8583, Japan
| | - N Tejos
- Instituto de Física, Pontificia Universidad Católica de Valparaíso, Casilla 4059, Valparaíso, Chile
| | - S D Ryder
- Department of Physics and Astronomy, Macquarie University, North Ryde, NSW 2109, Australia
| | - E M Sadler
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia.,Sydney Institute for Astronomy, School of Physics, University of Sydney, Sydney, NSW 2006, Australia
| | - R M Shannon
- Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, VIC 3122, Australia.
| | - S Simha
- University of California Observatories-Lick Observatory, University of California, Santa Cruz, CA 95064, USA
| | - C K Day
- Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, VIC 3122, Australia
| | - M McQuinn
- Astronomy Department, University of Washington, Seattle, WA 98195, USA
| | - F O North-Hickey
- International Centre for Radio Astronomy Research, Curtin University, Bentley, WA 6102, Australia
| | - S Bhandari
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - W R Arcus
- International Centre for Radio Astronomy Research, Curtin University, Bentley, WA 6102, Australia
| | - V N Bennert
- Physics Department, California Polytechnic State University, San Luis Obispo, CA 93407, USA
| | - J Burchett
- Instituto de Física, Pontificia Universidad Católica de Valparaíso, Casilla 4059, Valparaíso, Chile
| | - M Bouwhuis
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia.,Nikhef, Science Park, Amsterdam, Netherlands
| | - R Dodson
- International Centre for Radio Astronomy Research, University of Western Australia, Crawley, Perth, WA 6009, Australia
| | - R D Ekers
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia.,International Centre for Radio Astronomy Research, Curtin University, Bentley, WA 6102, Australia
| | - W Farah
- Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, VIC 3122, Australia
| | - C Flynn
- Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, VIC 3122, Australia
| | - C W James
- International Centre for Radio Astronomy Research, Curtin University, Bentley, WA 6102, Australia
| | - M Kerr
- Space Science Division, Naval Research Laboratory, Washington, DC 20375, USA
| | - E Lenc
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - E K Mahony
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - J O'Meara
- W. M. Keck Observatory, Waimea, HI 96743, USA
| | - S Osłowski
- Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, VIC 3122, Australia
| | - H Qiu
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia.,Sydney Institute for Astronomy, School of Physics, University of Sydney, Sydney, NSW 2006, Australia
| | - T Treu
- Department of Physics and Astronomy, University of California, Los Angeles, CA 90095, USA
| | - V U
- Department of Physics and Astronomy, University of California, Irvine, CA 92697, USA
| | - T J Bateman
- Sydney Institute for Astronomy, School of Physics, University of Sydney, Sydney, NSW 2006, Australia
| | - D C-J Bock
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - R J Bolton
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - A Brown
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - J D Bunton
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - A P Chippendale
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - F R Cooray
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - T Cornwell
- Tim Cornwell Consulting, 17 Elgan Crescent, Sandbach CW11 1LD, UK
| | - N Gupta
- Inter-University Centre for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411 007, India
| | - D B Hayman
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - M Kesteven
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - B S Koribalski
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - A MacLeod
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - N M McClure-Griffiths
- Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611, Australia
| | - S Neuhold
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - R P Norris
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia.,Western Sydney University, Locked Bag 1797, Penrith South, NSW 2751, Australia
| | - M A Pilawa
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - R-Y Qiao
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - J Reynolds
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - D N Roxby
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - T W Shimwell
- ASTRON, Netherlands Institute for Radio Astronomy, Postbus 2, 7990 AA Dwingeloo, Netherlands
| | - M A Voronkov
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
| | - C D Wilson
- Commonwealth Science and Industrial Research Organisation, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia
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Allen B, Dodson R, Zuercher J. Eat. Support. Live. Examining the Weight and Health-related Concerns of Postpartum Moms in East St. Louis. J Acad Nutr Diet 2017. [DOI: 10.1016/j.jand.2017.08.106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Dobrinskikh E, Purohit S, Dodson R, Shtofman R, Al-Juboori S, Aftab M, Reece T, Cornwell W, Ambardekar A. Increased Aortic Vascular Fibrosis with Prolonged Continuous-Flow Left Ventricular Assist Device Support. J Heart Lung Transplant 2017. [DOI: 10.1016/j.healun.2017.01.324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Eng J, Dodson R, Pham B, Kloor J, DeVan A, Doptis R, Harrison B, Leinwand L, Fleenor B. Overfed Burmese pythons undergo physiological remodeling of the aorta (867.5). FASEB J 2014. [DOI: 10.1096/fasebj.28.1_supplement.867.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Jason Eng
- Integrative Physiology University of ColoradoBoulderCOUnited States
| | - R. Dodson
- Department of Surgery University of ColoradoDenverCOUnited States
| | - Bryant Pham
- Integrative Physiology University of ColoradoBoulderCOUnited States
| | - Jackson Kloor
- Integrative Physiology University of ColoradoBoulderCOUnited States
| | - Allison DeVan
- Integrative Physiology University of ColoradoBoulderCOUnited States
| | - Ryan Doptis
- Molecular Cellular Integrative Physiology University of ColoradoBoulderCOUnited States
| | - Brooke Harrison
- Molecular Cellular Integrative Physiology University of ColoradoBoulderCOUnited States
| | - Leslie Leinwand
- Molecular Cellular Integrative Physiology University of ColoradoBoulderCOUnited States
| | - Bradley Fleenor
- Kinesiology and Health Promotion University of KentuckyLexingtonKYUnited States
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Willard ST, Dickerson T, Dodson R, Weis A, Godfrey RW. Administration of 6-methoxybenzoxazolinone (MBOA) does not augment ovulatory responses in St. Croix White ewes superovulated with PMSG. Anim Reprod Sci 2006; 93:280-91. [PMID: 16154300 DOI: 10.1016/j.anireprosci.2005.08.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2005] [Accepted: 08/04/2005] [Indexed: 11/22/2022]
Abstract
The objective of this investigation was to examine the effects of 6-methoxy-benzoxazolinone (MBOA), a plant compound that resembles melatonin and alters ovarian function in rodents, in combination with PMSG on superovulatory responses in the cycling ewe. In Experiment I, St. Croix White ewes (n = 44) were synchronized (intra-vaginal progestin sponge) for 14days followed by hCG (750 IU) at 1 day after sponge removal (day 0). Ewes were assigned to one of six treatments administered on day -1: Control (no PMSG or MBOA; n = 7); PMSG (1000 IU i.m.; n = 7); Low MBOA (0.43 mg/kg i.m.; n = 7); High MBOA (1.15 mg/kg i.m.; n = 7); Low MBOA + PMSG (n = 8); High MBOA + PMSG (n = 8). In Experiment II, St. Croix White ewes (n = 24) were synchronized (progestin CIDR) for 14 days followed by hCG on day 1 after CIDR removal (day 0). Ewes were assigned to one of three treatments administered on day -1: Control (n = 8); PMSG (n = 8); Low MBOA+PMSG (n = 8). Laparoscopy was performed on day 9 to assess numbers of corpora lutea (CL) and visible follicles on each ovary. Blood samples were collected on day -13, -1, 0, 1, and days 6 or 7-12 for analysis of serum progesterone (P4) by RIA. Treatment groups receiving PMSG (alone or with MBOA) exhibited greater (P < 0.05) serum concentrations of P4 post-synchrony than Control and MBOA-only groups. Ovulation rate was lower (P < 0.05) for Control and MBOA-only treated ewes than ewes receiving PMSG. Ovulation rate in ewes treated with MBOA alone was similar (P > 0.10) to Controls, and PMSG treatment alone did not differ (P > 0.10) from MBOA + PMSG treatment. Ewes treated with PMSG alone did not differ (P > 0.10) in follicle number from High MBOA + PMSG treated ewes, however, Low MBOA + PMSG treated ewes had greater numbers of follicles at day 9 (P < 0.05) than the PMSG or High MBOA + PMSG groups in Experiment I; although, this was not replicated in Experiment II with numbers of follicles in the Low MBOA + PMSG group being similar (P > 0.10) to PMSG alone. In summary, the addition of MBOA in combination with PMSG as part of a synchronization-superovuation protocol in the ewe did not increase ovulation rate.
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Affiliation(s)
- S T Willard
- Department of Animal and Dairy Sciences, Mississippi State University, Box 9815-CVM Wise Center, Mississippi State, MS 39762, USA.
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9
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Fleischmann RD, Alland D, Eisen JA, Carpenter L, White O, Peterson J, DeBoy R, Dodson R, Gwinn M, Haft D, Hickey E, Kolonay JF, Nelson WC, Umayam LA, Ermolaeva M, Salzberg SL, Delcher A, Utterback T, Weidman J, Khouri H, Gill J, Mikula A, Bishai W, Jacobs WR, Venter JC, Fraser CM. Whole-genome comparison of Mycobacterium tuberculosis clinical and laboratory strains. J Bacteriol 2002; 184:5479-90. [PMID: 12218036 PMCID: PMC135346 DOI: 10.1128/jb.184.19.5479-5490.2002] [Citation(s) in RCA: 492] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Virulence and immunity are poorly understood in Mycobacterium tuberculosis. We sequenced the complete genome of the M. tuberculosis clinical strain CDC1551 and performed a whole-genome comparison with the laboratory strain H37Rv in order to identify polymorphic sequences with potential relevance to disease pathogenesis, immunity, and evolution. We found large-sequence and single-nucleotide polymorphisms in numerous genes. Polymorphic loci included a phospholipase C, a membrane lipoprotein, members of an adenylate cyclase gene family, and members of the PE/PPE gene family, some of which have been implicated in virulence or the host immune response. Several gene families, including the PE/PPE gene family, also had significantly higher synonymous and nonsynonymous substitution frequencies compared to the genome as a whole. We tested a large sample of M. tuberculosis clinical isolates for a subset of the large-sequence and single-nucleotide polymorphisms and found widespread genetic variability at many of these loci. We performed phylogenetic and epidemiological analysis to investigate the evolutionary relationships among isolates and the origins of specific polymorphic loci. A number of these polymorphisms appear to have occurred multiple times as independent events, suggesting that these changes may be under selective pressure. Together, these results demonstrate that polymorphisms among M. tuberculosis strains are more extensive than initially anticipated, and genetic variation may have an important role in disease pathogenesis and immunity.
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Affiliation(s)
- R D Fleischmann
- The Institute for Genomic Research, Rockville, Maryland 20850, USA.
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11
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Dodson R. The life of Don Pedro Jaramillo: benefactor of humanity. Perspect Mex Am Stud 2001; 1:69-74. [PMID: 11617916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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12
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Abstract
BACKGROUND Anthophyllite asbestos has been reported to cause asbestosis, lung cancer, mesothelioma, and pleural plaques in occupationally exposed workers. Anthophyllite has also been associated with pleural plaques in Finland and Japan among those who live near mines and mills and have neighborhood or environmental exposure. METHODS We evaluated a 38-year-old patient with pleural mesothelioma who lived, attended school, and delivered newspapers near a manufacturing facility that used exclusively anthophyllite asbestos fiber from ages 8-17 years. He had no work exposure to asbestos. RESULTS The pleural mesothelioma was an epithelial type with tubulopapillary structures and was treated with an extrapleural pneumonectomy followed by radiation therapy. The malignant cells were positive by immunohistochemistry for cytokeratin but negative for carcinoembryonic antigen, S100, B72.3, and leu M1 antigen. Anthophyllite fibers were > 5 microm in length in lung tissue compared to 3 microm from a general population study. CONCLUSIONS Anthophyllite asbestos has been associated with neighborhood environmental exposure and pleural plaques; we now report a neighborhood exposure and pleural mesothelioma.
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Affiliation(s)
- W N Rom
- Division of Pulmonary and Critical Care Medicine, NYU School of Medicine, Bellevue, NY 10016, USA.
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13
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Read TD, Brunham RC, Shen C, Gill SR, Heidelberg JF, White O, Hickey EK, Peterson J, Utterback T, Berry K, Bass S, Linher K, Weidman J, Khouri H, Craven B, Bowman C, Dodson R, Gwinn M, Nelson W, DeBoy R, Kolonay J, McClarty G, Salzberg SL, Eisen J, Fraser CM. Genome sequences of Chlamydia trachomatis MoPn and Chlamydia pneumoniae AR39. Nucleic Acids Res 2000; 28:1397-406. [PMID: 10684935 PMCID: PMC111046 DOI: 10.1093/nar/28.6.1397] [Citation(s) in RCA: 580] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The genome sequences of Chlamydia trachomatis mouse pneumonitis (MoPn) strain Nigg (1 069 412 nt) and Chlamydia pneumoniae strain AR39 (1 229 853 nt) were determined using a random shotgun strategy. The MoPn genome exhibited a general conservation of gene order and content with the previously sequenced C.trachomatis serovar D. Differences between C.trachomatis strains were focused on an approximately 50 kb 'plasticity zone' near the termination origins. In this region MoPn contained three copies of a novel gene encoding a >3000 amino acid toxin homologous to a predicted toxin from Escherichia coli O157:H7 but had apparently lost the tryptophan biosyntheis genes found in serovar D in this region. The C. pneumoniae AR39 chromosome was >99.9% identical to the previously sequenced C.pneumoniae CWL029 genome, however, comparative analysis identified an invertible DNA segment upstream of the uridine kinase gene which was in different orientations in the two genomes. AR39 also contained a novel 4524 nt circular single-stranded (ss)DNA bacteriophage, the first time a virus has been reported infecting C. pneumoniae. Although the chlamydial genomes were highly conserved, there were intriguing differences in key nucleotide salvage pathways: C.pneumoniae has a uridine kinase gene for dUTP production, MoPn has a uracil phosphororibosyl transferase, while C.trachomatis serovar D contains neither gene. Chromosomal comparison revealed that there had been multiple large inversion events since the species divergence of C.trachomatis and C.pneumoniae, apparently oriented around the axis of the origin of replication and the termination region. The striking synteny of the Chlamydia genomes and prevalence of tandemly duplicated genes are evidence of minimal chromosome rearrangement and foreign gene uptake, presumably owing to the ecological isolation of the obligate intracellular parasites. In the absence of genetic analysis, comparative genomics will continue to provide insight into the virulence mechanisms of these important human pathogens.
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Affiliation(s)
- T D Read
- The Institute for Genomic Research, 9712 Medical Center Drive, Rockville, MD 20850, USA
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14
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Fraser CM, Norris SJ, Weinstock GM, White O, Sutton GG, Dodson R, Gwinn M, Hickey EK, Clayton R, Ketchum KA, Sodergren E, Hardham JM, McLeod MP, Salzberg S, Peterson J, Khalak H, Richardson D, Howell JK, Chidambaram M, Utterback T, McDonald L, Artiach P, Bowman C, Cotton MD, Fujii C, Garland S, Hatch B, Horst K, Roberts K, Sandusky M, Weidman J, Smith HO, Venter JC. Complete genome sequence of Treponema pallidum, the syphilis spirochete. Science 1998; 281:375-88. [PMID: 9665876 DOI: 10.1126/science.281.5375.375] [Citation(s) in RCA: 697] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The complete genome sequence of Treponema pallidum was determined and shown to be 1,138,006 base pairs containing 1041 predicted coding sequences (open reading frames). Systems for DNA replication, transcription, translation, and repair are intact, but catabolic and biosynthetic activities are minimized. The number of identifiable transporters is small, and no phosphoenolpyruvate:phosphotransferase carbohydrate transporters were found. Potential virulence factors include a family of 12 potential membrane proteins and several putative hemolysins. Comparison of the T. pallidum genome sequence with that of another pathogenic spirochete, Borrelia burgdorferi, the agent of Lyme disease, identified unique and common genes and substantiates the considerable diversity observed among pathogenic spirochetes.
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Affiliation(s)
- C M Fraser
- Institute for Genomic Research, Rockville, MD 20850, USA.
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15
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Fraser CM, Casjens S, Huang WM, Sutton GG, Clayton R, Lathigra R, White O, Ketchum KA, Dodson R, Hickey EK, Gwinn M, Dougherty B, Tomb JF, Fleischmann RD, Richardson D, Peterson J, Kerlavage AR, Quackenbush J, Salzberg S, Hanson M, van Vugt R, Palmer N, Adams MD, Gocayne J, Weidman J, Utterback T, Watthey L, McDonald L, Artiach P, Bowman C, Garland S, Fuji C, Cotton MD, Horst K, Roberts K, Hatch B, Smith HO, Venter JC. Genomic sequence of a Lyme disease spirochaete, Borrelia burgdorferi. Nature 1997; 390:580-6. [PMID: 9403685 DOI: 10.1038/37551] [Citation(s) in RCA: 1498] [Impact Index Per Article: 55.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The genome of the bacterium Borrelia burgdorferi B31, the aetiologic agent of Lyme disease, contains a linear chromosome of 910,725 base pairs and at least 17 linear and circular plasmids with a combined size of more than 533,000 base pairs. The chromosome contains 853 genes encoding a basic set of proteins for DNA replication, transcription, translation, solute transport and energy metabolism, but, like Mycoplasma genitalium, it contains no genes for cellular biosynthetic reactions. Because B. burgdorferi and M. genitalium are distantly related eubacteria, we suggest that their limited metabolic capacities reflect convergent evolution by gene loss from more metabolically competent progenitors. Of 430 genes on 11 plasmids, most have no known biological function; 39% of plasmid genes are paralogues that form 47 gene families. The biological significance of the multiple plasmid-encoded genes is not clear, although they may be involved in antigenic variation or immune evasion.
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Affiliation(s)
- C M Fraser
- Institute for Genomic Research, Rockville, Maryland 20850, USA
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16
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Tomb JF, White O, Kerlavage AR, Clayton RA, Sutton GG, Fleischmann RD, Ketchum KA, Klenk HP, Gill S, Dougherty BA, Nelson K, Quackenbush J, Zhou L, Kirkness EF, Peterson S, Loftus B, Richardson D, Dodson R, Khalak HG, Glodek A, McKenney K, Fitzegerald LM, Lee N, Adams MD, Hickey EK, Berg DE, Gocayne JD, Utterback TR, Peterson JD, Kelley JM, Cotton MD, Weidman JM, Fujii C, Bowman C, Watthey L, Wallin E, Hayes WS, Borodovsky M, Karp PD, Smith HO, Fraser CM, Venter JC. The complete genome sequence of the gastric pathogen Helicobacter pylori. Nature 1997; 388:539-47. [PMID: 9252185 DOI: 10.1038/41483] [Citation(s) in RCA: 2543] [Impact Index Per Article: 94.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Helicobacter pylori, strain 26695, has a circular genome of 1,667,867 base pairs and 1,590 predicted coding sequences. Sequence analysis indicates that H. pylori has well-developed systems for motility, for scavenging iron, and for DNA restriction and modification. Many putative adhesins, lipoproteins and other outer membrane proteins were identified, underscoring the potential complexity of host-pathogen interaction. Based on the large number of sequence-related genes encoding outer membrane proteins and the presence of homopolymeric tracts and dinucleotide repeats in coding sequences, H. pylori, like several other mucosal pathogens, probably uses recombination and slipped-strand mispairing within repeats as mechanisms for antigenic variation and adaptive evolution. Consistent with its restricted niche, H. pylori has a few regulatory networks, and a limited metabolic repertoire and biosynthetic capacity. Its survival in acid conditions depends, in part, on its ability to establish a positive inside-membrane potential in low pH.
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Affiliation(s)
- J F Tomb
- Institute for Genomic Research, Rockville, Maryland 20850, USA.
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17
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Pye J, O'Loughlin C, Dodson R, Pye L. Improving rural health: HeartSmart--an opportunity for family physician community involvement. Fam Med 1993; 25:585-8. [PMID: 8243906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
BACKGROUND Cardiovascular disease is a major cause of morbidity and mortality among adults in the United States. Evidence shows that risk factors for cardiovascular disease appearing during childhood are reliable predictors of cardiovascular illness in adulthood. An educational program to alter risk factors present in children is needed to help prevent future disease. This paper describes HeartSmart, a cross-age teaching program that was developed by a family physician in a rural location. The purpose of the program was to improve cardiovascular health knowledge of sixth-grade students. METHODS Under supervision of the family physician, the local hospital's cardiac rehabilitation unit taught cardiovascular disease prevention principles to a group of high school seniors, who then developed and taught a cardiovascular disease prevention program to sixth-grade students. Pre- and post-testing of the sixth grader's cardiovascular health knowledge was conducted. RESULTS Sixth-grade students demonstrated improved knowledge of cardiovascular fitness principles following the program. CONCLUSIONS HeartSmart exemplifies a program developed by a family physician that can be instituted in many communities to educate children about cardiovascular fitness and disease prevention principles.
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Affiliation(s)
- J Pye
- Department of Family Medicine, Medical College of Georgia
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18
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Berkow RL, Schlabach L, Dodson R, Benjamin WH, Pettit GR, Rustagi P, Kraft AS. In vivo administration of the anticancer agent bryostatin 1 activates platelets and neutrophils and modulates protein kinase C activity. Cancer Res 1993; 53:2810-5. [PMID: 8504423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Bryostatin 1 is a naturally occurring macrocyclic lactone which when applied to cells in culture activates protein kinase C (PKC). In vivo bryostatin 1 functions as an anticancer agent with activity against murine lymphomas, leukemias, and melanoma. Because all organs and tissues contain PKC, normal cells would also be a likely target for this agent. Here we demonstrate that in vivo administration of bryostatin 1 activates platelets over a dose range of 0.4 to 40 micrograms/kg with half-maximal activation occurring at 3 micrograms/kg and stimulation of neutrophils over a similar dose range. This in vivo activation of neutrophils is associated with a rapid decrease in measurable cytosolic PKC, a finding consistent with translocation of the enzyme to the membrane. In contrast, no statistically significant change in PKC location was found in liver, spleen, brain, or L10A B-cell lymphoma. However, in culture the L10A lymphoma did respond to bryostatin 1 with translocation of PKC. To evaluate whether the lack of effect of bryostatin 1 on PKC in organs was secondary to rapid degradation, we developed a bioassay to measure the levels of bryostatin 1 in the blood. To measure the presence of bryostatin 1, human neutrophils were incubated with plasma from mice given injections of different concentrations of bryostatin 1. Using this assay, bryostatin 1 at levels as low as 60 nM could be measured in the plasma. A time course with this bioassay demonstrated that less than 10% of the bryostatin 1 injected was detectable after 2.5 min. These results demonstrate that bryostatin 1 is capable of activating platelets and neutrophils and modulating PKC in vivo. The lack of effect of bryostatin 1 on specific organs may be secondary to the rapid clearance/degradation of this compound from the blood.
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Affiliation(s)
- R L Berkow
- Division of Hematology/Oncology, University of Alabama, Birmingham 35294
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19
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Pei L, Dodson R, Schoderbek WE, Maurer RA, Mayo KE. Regulation of the alpha inhibin gene by cyclic adenosine 3',5'-monophosphate after transfection into rat granulosa cells. Mol Endocrinol 1991; 5:521-34. [PMID: 1717833 DOI: 10.1210/mend-5-4-521] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Inhibin gene expression in the ovary is stimulated by FSH, which uses cAMP as an intracellular second messenger. To examine further the transcriptional regulation of the alpha inhibin gene by FSH and cAMP, we have isolated and characterized a genomic clone that contains the entire rat alpha inhibin gene. Sequence analysis of the alpha inhibin promoter region revealed several potential cAMP response elements (CREs) and transcription factor AP2-binding sites that might mediate cAMP regulation. To determine the functional importance of these sequences, fusion genes including the alpha inhibin 5' flanking region linked to a luciferase reporter gene were transiently transfected into primary granulosa cells isolated from immature rats. These fusion genes were both expressed and regulated by the adenylyl cyclase activator forskolin in transfected granulosa cells. Analysis of a series of 5' deletion mutants indicated that a construct containing as little as 170 basepairs up-stream of the alpha inhibin start site, which includes a single imperfect CRE and no AP2 sites, was regulated by forskolin. DNAse footprinting was used to demonstrate that bacterially expressed CRE-binding protein (CREB) binds to this CRE located 122 basepairs up-stream of the alpha inhibin gene transcriptional start site. To investigate further the role of this CRE in alpha inhibin gene expression, site-specific mutagenesis of the CRE was performed. The alpha inhibin promoter containing a mutated CRE was not regulated by forskolin in granulosa cells and did not bind the CREB protein. Interestingly, mutation of the CRE also substantially reduced basal expression of the alpha inhibin promoter. Lastly, a gel mobility shift assay was used to examine CRE-binding proteins from granulosa cell extracts. Granulosa cells contain a protein that specifically interacts with CRE-containing oligonucleotides or with the alpha inhibin promoter and that is recognized by antibodies against the CREB protein. Our results suggest that CREB or related transcription factors play an important role in both basal and cAMP-regulated expression of the alpha inhibin gene in ovarian granulosa cells.
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Affiliation(s)
- L Pei
- Department of Biochemistry, Northwestern University, Evanston, Illinois 60208
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20
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Baser ME, Kennedy TP, Dodson R, Rao NV, Rawlings W, Hoidal JR. Hydroxyl radical generating activity of hydrous but not calcined kaolin is prevented by surface modification with dipalmitoyl lecithin. J Toxicol Environ Health 1990; 29:99-108. [PMID: 2299691 DOI: 10.1080/15287399009531375] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The catalytic activity of kaolin, an aluminum silicate, for generating hydroxyl radicals (.OH) from hydrogen peroxide (H2O2) was studied in a chemical system that measured .OH as evolution of methane (CH4) from dimethyl sulfoxide. In the presence of a reducing agent and 10 mM H2O2, hydrous and calcined kaolin generated mean +/- SE CH4 concentrations of 1634 +/- 328 and 1395 +/- 29 ppm, respectively. Surface modification with dipalmitoyl lecithin, the lipid of pulmonary surfactant, blocked generation of .OH in hydrous kaolin (38 +/- 38 ppm CH4) but not in calcined kaolin (875 +/- 262 ppm CH4). The catalytic activity of kaolin for producing .OH from H2O2 may be important in the pathogenesis of kaolin toxicity, and calcined kaolin may be more toxic than hydrous kaolin because the calcined form is resistant to surface modification by lipids of pulmonary surfactant.
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Affiliation(s)
- M E Baser
- Department of Environmental Health Sciences, Johns Hopkins School of Hygiene and Public Health, Baltimore, MD 21205
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21
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Baser ME, Kennedy TP, Dodson R, Rawlings W, Rao NV, Hoidal JR. Differences in lung function and prevalence of pneumoconiosis between two kaolin plants. Br J Ind Med 1989; 46:773-6. [PMID: 2590641 PMCID: PMC1009866 DOI: 10.1136/oem.46.11.773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
To investigate the origin of differences in previously published pulmonary function studies of workers in kaolin plants in Georgia, spirometric and radiographic data collected in a cross sectional survey of two large plants were analysed. As compared with workers in plant 2, workers in plant 1 had a 2.7-fold greater prevalence of pneumoconiosis and a mean 0.361 decrement in adjusted forced vital capacity. Our previous finding that exposure to kaolin was not associated with a decrement in lung function may have resulted from failure to consider differences between the plants.
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Affiliation(s)
- M E Baser
- Department of Environmental Health Sciences, Johns Hopkins School of Hygiene and Public Health, Baltimore, Maryland
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22
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Abstract
Sacrococcygeal pain can arise from the sacrococcygeal joint, from contiguous structures sharing the same innervation, or from distant sites. True coccygodynia consists of pain arising from the sacrococcygeal joint, whereas pseudococcygodynia consists of pain referred to but not arising from the coccyx. Coccygodnia can usually be distinguished from pseudococcygodynia by physical examination with the diagnosis being confirmed by injection of local anesthetic into the sacrococcygeal joint. The etiology of pain not relieved by intraarticular injection can be further defined by selective neuroblockade. A method for defining the anatomic basis for sacrococcygeal pain is presented as well as a discussion of the relevant anatomy and differential diagnosis of sacrococcygeal pain.
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Affiliation(s)
- R B Traycoff
- Department of Medicine, Southern Illinois University School of Medicine, Springfield 62708
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23
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Kennedy TP, Dodson R, Rao NV, Ky H, Hopkins C, Baser M, Tolley E, Hoidal JR. Dusts causing pneumoconiosis generate .OH and produce hemolysis by acting as Fenton catalysts. Arch Biochem Biophys 1989; 269:359-64. [PMID: 2537062 DOI: 10.1016/0003-9861(89)90118-5] [Citation(s) in RCA: 87] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Silicates causing pneumoconiosis function as Fenton catalysts to generate hydroxyl radicals (.OH) when incubated with hydrogen peroxide and a reducing substance. In contrast, silicates which do not cause pneumoconiosis demonstrate no Fenton activity. Catalytic activity is decreased by pretreatment of silicates with the iron chelators deferoxamine or transferrin. Hemolysis from silicates is decreased by interventions which remove superoxide anion or hydrogen peroxide from the medium, or by pretreatment of dusts with iron chelators. Thus, asbestos and nonfibrous silicates may cause pneumoconiosis through a common oxidant mechanism by catalyzing production of toxic .OH radicals in the lung.
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Affiliation(s)
- T P Kennedy
- Pulmonary Division, University of Tennessee, Memphis 38163
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24
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Heber D, Dodson R, Peterson M, Channabasavaiah KC, Stewart JM, Swerdloff RS. Counteractive effects of agonistic and antagonistic gonadotropin-releasing hormone analogs on spermatogenesis: sites of action. Fertil Steril 1984; 41:309-13. [PMID: 6421624 DOI: 10.1016/s0015-0282(16)47610-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Both gonadotropin-releasing hormone (GnRH) agonistic and antagonistic analogs have been shown to inhibit reproductive hormonal function. While predictable and complete suppression of spermatogenesis is the ultimate goal of a number of clinical studies aimed at developing male contraceptive agents based on GnRH analogs, neither class of analog has been shown to completely inhibit spermatogenesis in man. The potential for a synergistic interaction of submaximal doses of these two classes of GnRH analogs was investigated in the present studies. In these studies 200 ng/day of a potent agonist (D-Leu6des-Gly10GnRH ethylamide) and 100 micrograms/day of a potent antagonist (NAc-L-Ala1, pCl-D-Phe2, D-Trp3,6GnRH) were administered subcutaneously, both alone and in combination, to adult male rats for 21 days. Serum gonadotropins and testosterone, pituitary GnRH receptor content, gonadal gonadotropin receptors, and intratesticular sperm counts were quantitated in each treatment group. Despite the ability of both GnRH agonists and antagonists to inhibit reproductive function when administered as single agents in this study, combined treatment with the two classes of GnRH analogs was less effective than either agent alone at these doses in the pharmacologic suppression of spermatogenesis.
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25
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Abstract
Instrument-marking tapes facilitate instrument preparation and packaging but can be responsible for increased surgical morbidity by fragmenting into the wound or harboring bacteria when old or damaged. Four cases of submandibular abscess formation and the potential failure of an oro-antral closure were directly attributed to the use of marking tapes.
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26
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Heber D, Dodson R, Stoskopf C, Peterson M, Swerdloff RS. Pituitary desensitization and the regulation of pituitary gonadotropin-releasing hormone (GnRH) receptors following chronic administration of a superactive GnRH analog and testosterone. Life Sci 1982; 30:2301-8. [PMID: 6287149 DOI: 10.1016/0024-3205(82)90257-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
We recently demonstrated that chronic daily administration of a superactive GnRH analog to intact rats resulted in an initial stimulation of serum LH levels with a subsequent return of LH levels to baseline at a time when testosterone levels were markedly decreased. These data demonstrated pituitary desensitization following chronic GnRH analog treatment. Administration of GnRH analog with a dose of testosterone which did not markedly lower serum LH levels when administered alone prevented the stimulation of LH secretion by analog. The present studies were undertaken to determine the effects of GnRH analog and testosterone administration on the regulation of pituitary GnRH receptors. Pituitary GnRH receptor binding was increased by analog treatment alone at 20 days and returned to control levels at 40 and 60 days of treatment in parallel to the observed changes in serum LH, demonstrating that one mechanism by which chronic GnRH analog treatment leads to pituitary desensitization is down-regulation of pituitary GnRH receptors. Testosterone administration alone decreased pituitary GnRH receptor binding. Combined GnRH analog and testosterone administration prevented the increase in pituitary GnRH receptors observed with analog administration alone. These studies demonstrate that change in pituitary GnRH receptor binding correlate with changes in serum LH and that the stimulatory effects of analog administration on LH are sensitive to inhibition by small doses of testosterone.
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27
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Heber D, Dodson R, Swerdloff RS, Channabasavaiah K, Stewart JM. Pituitary receptor site blockade by a gonadotropin-releasing hormone antagonist in vivo: mechanism of action. Science 1982; 216:420-1. [PMID: 6280278 DOI: 10.1126/science.6280278] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Administration of a potent gonadotropin-releasing hormone (GnRH) antagonist [Nac-L-Ala1,pCl-D-Phe2,D-Trp3,6]GnRH as a single subcutaneous injection to castrated adult male rats reduced, by more than 90 percent, both serum luteinizing hormone concentrations and specific pituitary GnRH receptor binding. This effect persisted for 24 hours. The dissociation rate of the antagonist from pituitary membrane homogenates was fourfold slower than the dissociation rate of a potent agonist. The prolonged in vivo inhibition of pituitary GnRH receptor binding and luteinizing hormone secretion by the GnRH antagonist may be mediated by the slower dissociation rate of the antagonist from its specific pituitary membrane receptor site.
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28
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Dodson R, Muir R. Additions and Corrections-Microbiological Transformations. VI. The Microbiological Armatization of Steroids. J Am Chem Soc 1961. [DOI: 10.1021/ja01485a642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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29
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Dodson R, Muir R. Additions and Corrections - Microbiological Transformations VI. The Microbiological Aromatization of Steroids. J Am Chem Soc 1961. [DOI: 10.1021/ja01485a647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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