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Morales AC, West CP, Peterson BN, Noh Y, Whelton AJ, Laskin A. Diversity of organic components in airborne waste discharged from sewer pipe repairs. Environ Sci Process Impacts 2023; 25:1670-1683. [PMID: 37682218 DOI: 10.1039/d3em00084b] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/09/2023]
Abstract
Air-discharged waste from commonly used trenchless technologies of sewer pipe repairs is an emerging and poorly characterized source of urban pollution. This study reports on the molecular-level characterization of the atmospherically discharged aqueous-phase waste condensate samples collected at four field sites of the sewer pipe repairs. The molecular composition of organic species in these samples was investigated using reversed-phase liquid chromatography coupled with a photodiode array detector and a high-resolution mass spectrometer equipped with interchangeable atmospheric pressure photoionization and electrospray ionization sources. The waste condensate components comprise a complex mixture of organic species that can partition between gas-, aqueous-, and solid-phases when water evaporates from the air-discharged waste. Identified organic species have broad variability in molecular weight, molecular structures, and carbon oxidation state, which also varied between the waste samples. All condensates contained complex mixtures of oxidized organics, N- and S-containing organics, condensed aromatics, and their functionalized derivatives that are directly released to the atmospheric environment during installations. Furthermore, semi-volatile, low volatility, and extremely low volatility organic compounds comprise 75-85% of the total compounds identified in the waste condensates. Estimates of the component-specific viscosities suggest that upon evaporation of water waste material would form the semi-solid and solid phases. The low volatilities and high viscosities of chemical components in these waste condensates will contribute to the formation of atmospheric secondary organic aerosols and atmospheric solid nanoplastic particles. Lastly, selected components expected in the condensates were quantified and found to be present at high concentrations (1-20 mg L-1) that may exceed regulatory limits.
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Affiliation(s)
- Ana C Morales
- College of Science, Department of Chemistry, Purdue University, West Lafayette, IN, USA.
| | - Christopher P West
- College of Science, Department of Chemistry, Purdue University, West Lafayette, IN, USA.
| | - Brianna N Peterson
- College of Science, Department of Chemistry, Purdue University, West Lafayette, IN, USA.
| | - Yoorae Noh
- Lyles School of Civil Engineering, Division of Environmental and Ecological Engineering, Purdue University, West Lafayette, IN, USA
| | - Andrew J Whelton
- Lyles School of Civil Engineering, Division of Environmental and Ecological Engineering, Purdue University, West Lafayette, IN, USA
| | - Alexander Laskin
- College of Science, Department of Chemistry, Purdue University, West Lafayette, IN, USA.
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West CP, Hsu YJ, MacFeely KT, Huston SM, Aridjis-Olivos BP, Morales AC, Laskin A. Volatility Measurements of Individual Components in Organic Aerosol Mixtures Using Temperature-Programmed Desorption-Direct Analysis in Real Time-High Resolution Mass Spectrometry. Anal Chem 2023; 95:7403-7408. [PMID: 37126857 DOI: 10.1021/acs.analchem.3c00923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Atmospheric organic aerosols (OA) have profound effects on air quality, visibility, and radiative forcing of climate. Quantitative assessment of gas-particle equilibrium of OA components is critical to understand formation, growth, distribution, and evolution of OA in the atmosphere. This study presents a novel ambient pressure measurement approach developed and tested for untargeted screening of individual components in complex OA mixtures, followed by targeted chemical speciation of identified species and assessment of their physicochemical properties such as saturation vapor pressure and enthalpies of sublimation/evaporation. The method employs temperature-programmed desorption (TPD) experiments coupled to "direct analysis in real time" (DART) ionization source and high resolution mass spectrometry (HRMS) detection. Progression of the mass spectra is acquired in the TPD experiments over a T = 25-350 °C temperature range, and extracted ion chromatograms (EIC) of individual species are used to infer their apparent enthalpies of sublimation/evaporation (ΔHsub*) and saturation vapor pressure (pT*, Pa, or CT*, μg m-3) as a function of T. We validate application of this method for analysis of selected organic compounds with known ΔHsub and CT values, which showed excellent agreement between our results and the existing data. We then extend these experiments to interrogate individual components in complex OA samples generated in the laboratory-controlled ozonolysis of α-pinene, limonene, and β-ocimene monoterpenes. The abundant OA species of interest are distinguished based on their accurate mass measurements, followed by quantitation of their apparent ΔHsub* and CT* values from the corresponding EIC records. Comparison of C298K* values derived from our experiments for the individual OA components with the corresponding estimates based on their elemental composition using a "molecular corridors" (MC) parametrization suggests that the MC calculations tend to overestimate the saturation vapor pressures of OA components. Presented results indicate very promising applicability of the TPD-DART-HRMS method for the untargeted analysis of organic molecules in OA and other environmental mixtures, enabling rapid detection and quantification of organic pollutants in the real-world condensed-phase samples at atmospheric pressure and without sample preparation.
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Affiliation(s)
- Christopher P West
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Yun-Jung Hsu
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Killian T MacFeely
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Shelby M Huston
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | | | - Ana C Morales
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Alexander Laskin
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
- Department of Earth, Atmospheric & Planetary Sciences, Purdue University, West Lafayette, Indiana 47907, United States
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West CP, Mesa Sanchez D, Morales AC, Hsu YJ, Ryan J, Darmody A, Slipchenko LV, Laskin J, Laskin A. Molecular and Structural Characterization of Isomeric Compounds in Atmospheric Organic Aerosol Using Ion Mobility-Mass Spectrometry. J Phys Chem A 2023; 127:1656-1674. [PMID: 36763810 DOI: 10.1021/acs.jpca.2c06459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Secondary organic aerosol (SOA) formed through multiphase atmospheric chemistry makes up a large fraction of airborne particles. The chemical composition and molecular structures of SOA constituents vary between different emission sources and aging processes in the atmosphere, which complicates their identification. In this work, we employ drift tube ion mobility spectrometry with quadrupole time-of-flight mass spectrometry (IM-MS) detection for rapid gas-phase separation and multidimensional characterization of isomers in two biogenic SOAs produced from ozonolysis of isomeric monoterpenes, d-limonene (LSOA) and α-pinene (PSOA). SOA samples were ionized using electrospray ionization (ESI) and characterized using IM-MS in both positive and negative ionization modes. The IM-derived collision cross sections in nitrogen gas (DTCCSN2 ) for individual SOA components were obtained using multifield and single-field measurements. A novel application of IM multiplexing/high-resolution demultiplexing methodology was employed to increase sensitivity, improve peak shapes, and augment mobility baseline resolution, which revealed several isomeric structures for the measured ions. For LSOA and PSOA samples, we report significant structural differences of the isomer structures. Molecular structural calculations using density functional theory combined with the theoretical modeling of CCS values provide insights into the structural differences between LSOA and PSOA constituents. The average DTCCSN2 values for monomeric SOA components observed as [M + Na]+ ions are 3-6% higher than those of their [M - H]- counterparts. Meanwhile, dimeric and trimeric isomer components in both samples showed an inverse trend with the relevant values of [M - H]- ions being 3-7% higher than their [M + Na]+ counterparts, respectively. The results indicate that the structures of Na+-coordinated oligomeric ions are more compact than those of the corresponding deprotonated species. The coordination with Na+ occurs on the oxygen atoms of the carbonyl groups leading to a compact configuration. Meanwhile, deprotonated molecules have higher DTCCSN2 values due to their elongated structures in the gas phase. Therefore, DTCCSN2 values of isomers in SOA mixtures depend strongly on the mode of ionization in ESI. Additionally, PSOA monomers and dimers exhibit larger DTCCSN2 values (1-4%) than their LSOA counterparts owing to more rigid structures. A cyclobutane ring is present with functional groups pointing in opposite directions in PSOA compounds, as compared to noncyclic flexible LSOA structures, forming more compact ions in the gas phase. Lastly, we investigated the effects of direct photolysis on the chemical transformations of selected individual PSOA components. We use IM-MS to reveal structural changes associated with aerosol aging by photolysis. This study illustrates the detailed molecular and structural descriptors for the detection and annotation of structural isomers in complex SOA mixtures.
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Affiliation(s)
- Christopher P West
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Daniela Mesa Sanchez
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Ana C Morales
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Yun-Jung Hsu
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Jackson Ryan
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Andrew Darmody
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States.,Department of Aeronautics and Aerospace Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Lyudmila V Slipchenko
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Julia Laskin
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Alexander Laskin
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States.,Department of Earth, Atmospheric & Planetary Sciences, Purdue University, West Lafayette, Indiana 47907, United States
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West CP, Morales AC, Ryan J, Misovich MV, Hettiyadura APS, Rivera-Adorno F, Tomlin JM, Darmody A, Linn BN, Lin P, Laskin A. Molecular investigation of the multi-phase photochemistry of Fe(III)-citrate in aqueous solution. Environ Sci Process Impacts 2023; 25:190-213. [PMID: 35634912 DOI: 10.1039/d1em00503k] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Iron (Fe) is ubiquitous in nature and found as FeII or FeIII in minerals or as dissolved ions Fe2+ or Fe3+ in aqueous systems. The interactions of soluble Fe have important implications for fresh water and marine biogeochemical cycles, which have impacts on global terrestrial and atmospheric environments. Upon dissolution of FeIII into natural aquatic systems, organic carboxylic acids efficiently chelate FeIII to form [FeIII-carboxylate]2+ complexes that undergo a wide range of photochemistry-induced radical reactions. The chemical composition and photochemical transformations of these mixtures are largely unknown, making it challenging to estimate their environmental impact. To investigate the photochemical process of FeIII-carboxylates at the molecular level, we conduct a comprehensive experimental study employing UV-visible spectroscopy, liquid chromatography coupled to photodiode array and high-resolution mass spectrometry detection, and oil immersion flow microscopy. In this study, aqueous solutions of FeIII-citrate were photolyzed under 365 nm light in an experimental setup with an apparent quantum yield of (φ) ∼0.02, followed by chemical analyses of reacted mixtures withdrawn at increment time intervals of the experiment. The apparent photochemical reaction kinetics of Fe3+-citrates (aq) were expressed as two generalized consecutive reactions of with the experimental rate constants of j1 ∼ 0.12 min-1 and j2 ∼ 0.05 min-1, respectively. Molecular characterization results indicate that R and I consist of both water-soluble organic and Fe-organic species, while P compounds are a mixture of water-soluble and colloidal materials. The latter were identified as Fe-carbonaceous colloids formed at long photolysis times. The carbonaceous content of these colloids was identified as unsaturated organic species with low oxygen content and carbon with a reduced oxidation state, indicative of their plausible radical recombination mechanism under oxygen-deprived conditions typical for the extensively photolyzed mixtures. Based on the molecular characterization results, we discuss the comprehensive reaction mechanism of FeIII-citrate photochemistry and report on the formation of previously unexplored colloidal reaction products, which may contribute to atmospheric and terrestrial light-absorbing materials in aquatic environments.
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Affiliation(s)
- Christopher P West
- Department of Chemistry, Purdue University, West Lafayette, IN, 47906, USA.
| | - Ana C Morales
- Department of Chemistry, Purdue University, West Lafayette, IN, 47906, USA.
| | - Jackson Ryan
- Department of Chemistry, Purdue University, West Lafayette, IN, 47906, USA.
| | - Maria V Misovich
- Department of Chemistry, Purdue University, West Lafayette, IN, 47906, USA.
| | | | | | - Jay M Tomlin
- Department of Chemistry, Purdue University, West Lafayette, IN, 47906, USA.
| | - Andrew Darmody
- Department of Aeronautics and Aerospace Engineering, Purdue University, West Lafayette, IN, USA
| | - Brittany N Linn
- Department of Chemistry, Purdue University, West Lafayette, IN, 47906, USA.
| | - Peng Lin
- Department of Chemistry, Purdue University, West Lafayette, IN, 47906, USA.
| | - Alexander Laskin
- Department of Chemistry, Purdue University, West Lafayette, IN, 47906, USA.
- Department of Earth, Atmospheric & Planetary Sciences, Purdue University, West Lafayette, IN, USA
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Morales AC, Tomlin JM, West CP, Rivera-Adorno FA, Peterson BN, Sharpe SAL, Noh Y, Sendesi SMT, Boor BE, Howarter JA, Moffet RC, China S, O'Callahan BT, El-Khoury PZ, Whelton AJ, Laskin A. Atmospheric emission of nanoplastics from sewer pipe repairs. Nat Nanotechnol 2022; 17:1171-1177. [PMID: 36203091 DOI: 10.1038/s41565-022-01219-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 08/22/2022] [Indexed: 06/16/2023]
Abstract
Nanoplastic particles are inadequately characterized environmental pollutants that have adverse effects on aquatic and atmospheric systems, causing detrimental effects to human health through inhalation, ingestion and skin penetration1-3. At present, it is explicitly assumed that environmental nanoplastics (EnvNPs) are weathering fragments of microplastic or larger plastic debris that have been discharged into terrestrial and aquatic environments, while atmospheric EnvNPs are attributed solely to aerosolization by wind and other mechanical forces. However, the sources and emissions of unintended EnvNPs are poorly understood and are therefore largely unaccounted for in various risk assessments4. Here we show that large quantities of EnvNPs may be directly emitted into the atmosphere as steam-laden waste components discharged from a technology commonly used to repair sewer pipes in urban areas. A comprehensive chemical analysis of the discharged waste condensate has revealed the abundant presence of insoluble colloids, which after drying form solid organic particles with a composition and viscosity consistent with EnvNPs. We suggest that airborne emissions of EnvNPs from these globally used sewer repair practices may be prevalent in highly populated urban areas5, and may have important implications for air quality and toxicological levels that need to be mitigated.
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Affiliation(s)
- Ana C Morales
- Department of Chemistry, Purdue University, West Lafayette, IN, USA
| | - Jay M Tomlin
- Department of Chemistry, Purdue University, West Lafayette, IN, USA
| | | | | | | | | | - Yoorae Noh
- Lyles School of Civil Engineering, Purdue University, West Lafayette, IN, USA
| | - Seyedeh M T Sendesi
- Lyles School of Civil Engineering, Purdue University, West Lafayette, IN, USA
| | - Brandon E Boor
- Lyles School of Civil Engineering, Purdue University, West Lafayette, IN, USA
| | - John A Howarter
- School of Materials Engineering, Purdue University, West Lafayette, IN, USA
| | | | - Swarup China
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Brian T O'Callahan
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Patrick Z El-Khoury
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Andrew J Whelton
- Lyles School of Civil Engineering, Purdue University, West Lafayette, IN, USA
- Department of Environmental and Ecological Engineering, Purdue University, West Lafayette, IN, USA
| | - Alexander Laskin
- Department of Chemistry, Purdue University, West Lafayette, IN, USA.
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Zhou Y, West CP, Hettiyadura APS, Pu W, Shi T, Niu X, Wen H, Cui J, Wang X, Laskin A. Molecular Characterization of Water-Soluble Brown Carbon Chromophores in Snowpack from Northern Xinjiang, China. Environ Sci Technol 2022; 56:4173-4186. [PMID: 35287433 DOI: 10.1021/acs.est.1c07972] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
This study reports molecular-level characterization of brown carbon (BrC) attributed to water-soluble organic carbon in six snowpack samples collected from northern Xinjiang, China. The molecular composition and light-absorbing properties of BrC chromophores were unraveled by application of high-performance liquid chromatography (HPLC) coupled to a photodiode array (PDA) detector and high-resolution mass spectrometry. The chromophores were classified into five major types, that is, (1) phenolic/lignin-derivedcompounds, (2) flavonoids, (3) nitroaromatics, (4) oxygenated aromatics, and (5) other chromophores. Identified chromophores account for ∼23-64% of the total light absorption measured by the PDA detector in the wavelength range of 300-370 nm. In the representative samples from urban and remote areas, oxygenated aromatics and nitroaromatics dominate the absorption in the wavelengths below and above 320 nm, respectively. The highly polluted urban sample shows the most complex HPLC-PDA chromatogram, and more other chromophores contribute to the bulk absorption. Phenolic/lignin-derived compounds are the most light-absorbing species in the soil-influenced sample. Chromophores in two remote samples exhibit ultraviolet-visible features distinct from other samples, which are attributed to flavonoids. Identification of individual chromophores and quantitative analysis of their optical properties are helpful for elucidating the roles of BrC in snow radiative balance and photochemistry.
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Affiliation(s)
- Yue Zhou
- Key Laboratory for Semi-Arid Climate Change of the Ministry of Education, College of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, China
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Christopher P West
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Anusha P S Hettiyadura
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Wei Pu
- Key Laboratory for Semi-Arid Climate Change of the Ministry of Education, College of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, China
| | - Tenglong Shi
- Key Laboratory for Semi-Arid Climate Change of the Ministry of Education, College of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, China
| | - Xiaoying Niu
- Key Laboratory for Semi-Arid Climate Change of the Ministry of Education, College of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, China
| | - Hui Wen
- Key Laboratory for Semi-Arid Climate Change of the Ministry of Education, College of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, China
| | - Jiecan Cui
- Key Laboratory for Semi-Arid Climate Change of the Ministry of Education, College of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, China
| | - Xin Wang
- Key Laboratory for Semi-Arid Climate Change of the Ministry of Education, College of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, China
- Institute of Surface-Earth System Science, Tianjin University, Tianjin 300072, China
| | - Alexander Laskin
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
- Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette, Indiana 47907, United States
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Hettiyadura APS, Garcia V, Li C, West CP, Tomlin J, He Q, Rudich Y, Laskin A. Chemical Composition and Molecular-Specific Optical Properties of Atmospheric Brown Carbon Associated with Biomass Burning. Environ Sci Technol 2021; 55:2511-2521. [PMID: 33499599 DOI: 10.1021/acs.est.0c05883] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
This study provides molecular insights into the light absorption properties of biomass burning (BB) brown carbon (BrC) through the chemical characterization of tar condensates generated from heated wood pellets at oxidative and pyrolysis conditions. Both liquid tar condensates separated into "darker oily" and "lighter aqueous" immiscible phases. The molecular composition of these samples was investigated using reversed-phase liquid chromatography coupled with a photodiode array detector and a high-resolution mass spectrometer. The results revealed two sets of BrC chromophores: (1) common to all four samples and (2) specific to the "oily" fractions. The common BrC chromophores consist of polar, monoaromatic species. The oil-specific BrC chromophores include less-polar and nonpolar polyaromatic compounds. The most-light-absorbing pyrolysis oily phase (PO) was aerosolized and size-separated using a cascade impactor to compare the composition and optical properties of the bulk versus the aerosolized BrC. The mass absorption coefficient (MAC300-500 nm) of aerosolized PO increased compared to that of the bulk, due to gas-phase partitioning of more volatile and less absorbing chromophores. The optical properties of the aerosolized PO were consistent with previously reported ambient BB BrC measurements. These results suggest the darkening of atmospheric BrC following non-reactive evaporation that transforms the optical properties and composition of aged BrC aerosols.
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Affiliation(s)
| | | | - Chunlin Li
- Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | | | | | - Quanfu He
- Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yinon Rudich
- Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
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Abstract
Physician burnout, a work-related syndrome involving emotional exhaustion, depersonalization and a sense of reduced personal accomplishment, is prevalent internationally. Rates of burnout symptoms that have been associated with adverse effects on patients, the healthcare workforce, costs and physician health exceed 50% in studies of both physicians-in-training and practicing physicians. This problem represents a public health crisis with negative impacts on individual physicians, patients and healthcare organizations and systems. Drivers of this epidemic are largely rooted within healthcare organizations and systems and include excessive workloads, inefficient work processes, clerical burdens, work-home conflicts, lack of input or control for physicians with respect to issues affecting their work lives, organizational support structures and leadership culture. Individual physician-level factors also play a role, with higher rates of burnout commonly reported in female and younger physicians. Effective solutions align with these drivers. For example, organizational efforts such as locally developed practice modifications and increased support for clinical work have demonstrated benefits in reducing burnout. Individually focused solutions such as mindfulness-based stress reduction and small-group programmes to promote community, connectedness and meaning have also been shown to be effective. Regardless of the specific approach taken, the problem of physician burnout is best addressed when viewed as a shared responsibility of both healthcare systems and individual physicians. Although our understanding of physician burnout has advanced considerably in recent years, many gaps in our knowledge remain. Longitudinal studies of burnout's effects and the impact of interventions on both burnout and its effects are needed, as are studies of effective solutions implemented in combination. For medicine to fulfil its mission for patients and for public health, all stakeholders in healthcare delivery must work together to develop and implement effective remedies for physician burnout.
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Affiliation(s)
- C P West
- Department of Medicine, Mayo Clinic, Rochester, MN, USA.,Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA
| | - L N Dyrbye
- Department of Medicine, Mayo Clinic, Rochester, MN, USA
| | - T D Shanafelt
- Department of Medicine, Stanford University Medical Center, Stanford, CA, USA
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Shin A, Camilleri M, Kolar G, Erwin P, West CP, Murad MH. Systematic review with meta-analysis: highly selective 5-HT4 agonists (prucalopride, velusetrag or naronapride) in chronic constipation. Aliment Pharmacol Ther 2014; 39:239-53. [PMID: 24308797 DOI: 10.1111/apt.12571] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Revised: 09/29/2013] [Accepted: 11/11/2013] [Indexed: 12/16/2022]
Abstract
BACKGROUND Highly selective 5-HT4 agonists have been suggested for the treatment of chronic constipation (CC). AIM To assess the effects of highly selective 5-HT4 agonists (prucalopride, velusetrag or naronapride) on patient-important clinical efficacy outcomes and safety in adults with CC. METHODS We searched the medical literature in January 2013 using MEDLINE/Pubmed, Embase, Cochrane Library, and Web of Science/Scopus for randomised, controlled trials of highly selective 5-HT4 agonists in adults with CC, with no minimum duration of therapy (maximum 12 weeks) or date limitations. Data were extracted from intention-to-treat analyses, pooled using a random-effects model, and reported as relative risk (RR), mean differences, or standardised mean differences with 95% confidence intervals (CI). RESULTS Main outcomes included stool frequency, Patient-Assessment of Constipation Quality of Life (PAC-QOL), PAC of symptoms (PAC-SYM) and adverse events. Thirteen eligible trials were identified: 11 prucalopride, 1 velusetrag, 1 naronapride. Relative to control, treatment with highly selective 5-HT4 agonists was superior for all outcomes: mean ≥3 spontaneous complete bowel movements (SCBM)/week (RR = 1.85; 95% CI 1.23-2.79); mean ≥1 SCBM over baseline (RR = 1.57; 95% CI 1.19, 2.06); ≥1 point improvement in PAC-QOL and PAC-SYM scores. The only active comparator trial of prucalopride and PEG3350 suggested PEG3350 is more efficacious for some end points. Adverse events were more common with highly selective 5-HT4 agonists, but were generally minor; headache was the most frequent. Most trials studied prucalopride. CONCLUSION Demonstration of efficacy on patient-important outcomes and a favourable safety profile support the continued use and development of highly selective 5-HT4 agonists in the treatment of chronic constipation.
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Affiliation(s)
- A Shin
- Clinical Enteric Neuroscience Translational and Epidemiological Research (C.E.N.T.E.R.), College of Medicine, Mayo Clinic, Rochester, MN, USA
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10
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Caldwell JD, Coffey KP, Jennings JA, Philipp D, Young AN, Tucker JD, Hubbell DS, Hess T, Looper ML, West CP, Savin MC, Popp MP, Kreider DL, Hallford DM, Rosenkrans CF. Performance by spring and fall-calving cows grazing with full, limited, or no access to toxic Neotyphodium coenophialum-infected tall fescue. J Anim Sci 2012; 91:465-76. [PMID: 22785163 DOI: 10.2527/jas.2011-4603] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Replacing toxic, wild-type Neotyphodium coenophialum-infected tall fescue (E+) with nontoxic, N. coenophialum-infected tall fescue (NE+) has improved cow performance, but producer acceptance of NE+ has been slow. The objective was to compare performance by spring- and fall-calving cows grazing either E+ or NE+ at different percentages of the total pasture area. Gelbvieh×Angus crossbred cows (n=178) were stratified by BW and age within calving season and allocated randomly to 1 of 14 groups representing 5 treatments for a 3-yr study: i) Fall-calving on 100% E+ (F100); ii) Spring-calving on 100% E+ (S100); iii) Fall-calving on 75% E+ and 25% NE+ (F75); iv) Spring-calving on 75% E+ and 25% NE+ (S75); and v) Spring-calving on 100% NE+ (SNE100). Groups allocated to F75 and S75 grazed E+ until approximately 28 d before breeding and weaning, then were then moved to their respective NE+ pasture area for 4 to 6 wk; those allocated to F100, S100, and SNE100 grazed their pastures throughout the entire year. Samples of tall fescue were gathered from specific cells within each pasture at the time cows were moved into that particular cell (∼1 sample/mo). Blood samples were collected from the cows at the start and end of the breeding season. Stocking rate for each treatment was 1 cow/ha. Forage IVDMD, CP, and total ergot alkaloid concentrations were affected (P<0.05) by the treatment×sampling date interaction. Hay offered, cow BW, and BCS at breeding, end of breeding, and at weaning were greater (P<0.05) from fall-calving vs. spring-calving. Cow BW at weaning was greater (P<0.05) from F75 and S75 vs. F100 and S100. The calving season×NE+ % interaction affected (P<0.05) calving rates. Preweaning calf BW gain, actual and adjusted weaning BW, ADG, sale price, and calf value at weaning were greater (P<0.05) from fall-calving vs. spring-calving and from SNE100 vs. S75 except for sale price which was greater (P<0.05) from S75 vs. SNE100. Cow concentrations of serum prolactin at breeding and serum NEFA at the end of breeding were affected (P<0.05) by the calving season×NE+ % interaction. Serum Zn and Cu concentrations from cows were affected (P<0.05) by calving season. A fall-calving season may be more desirable for cows grazing E+, resulting in greater calving rates, cow performance, and calf BW at weaning, whereas limited access to NE+ may increase calving rates, serum prolactin, and NEFA concentrations during certain times in the production cycle, particularly in spring-calving cows.
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Affiliation(s)
- J D Caldwell
- Department of Agriculture, Lincoln University, Jefferson City, MO 65101, USA
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11
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Abstract
In May 2007, switchgrass (Panicum virgatum L.) cv. Alamo and a breeding line, OSU-NSL 2001-1, were planted at the Arkansas Agricultural Research and Extension Center, Fayetteville. In August 2008, a high incidence of dark brown-to-black rectangular foliar lesions delineated by major veins was observed throughout plots of both lines. Lesions covered 25% to nearly 100% of total leaf tissue. Similar symptoms were also observed on unknown switchgrass cultivars in Benton County in northwest Arkansas and in St. Francis County in east-central Arkansas, suggesting that the disease was widely distributed throughout the state. The pathogen produced epiphyllous and adaxial masses of dark brown-to-black telia from erumpent fissures on leaf surfaces. Dark brown teliospores were observed under magnification and were two-celled, oblong to ellipsoid, and 33 ± 3.5 μm long with an apical cell width of 17.5 ± 2.7 μm and basal cell width of 16.2 ± 2.8 μm (reported as mean ± standard deviation, n = 25). Pedicles were colorless to light brown and measured 25.4 ± 9.2 μm (n = 25). In June 2009, at the Fayetteville Research and Extension Center, several second-year stands of switchgrass developed amphigenous and adaxial foliar lesions containing urediniospores. The uredia were globose and finely echinulate, measuring 23.1 ± 2.2 μm (n = 25) with brown cell walls. Teliospore and urediniospore morphology from all collections was consistent with Puccinia emaculata Schw. (2). Genomic DNA was extracted from a representative infected leaf of cv. Alamo, collected in Fayetteville, AR in June 2009, and amplified by PCR with primer sets PRITS1F (3) and ITS4B (1), which amplified an 803-bp fragment of rDNA encoding the first internal transcribed spacer (ITS1), 5.8S subunit, and second internal transcribed spacer (ITS2). The fragment was cloned into pGEM T Easy (Promega Corp, Madison, WI) and sequenced. A BLAST search of GenBank revealed that the fragment was most similar to the rDNA of P. emaculata (GenBank Accession No. EU915294.1; 755 of 758 bases matching; 99% identity) previously reported as a pathogen on switchgrass in Tennessee (3). The incidence and severity of rust on the widely planted switchgrass cv. Alamo is considerable cause for concern as efforts are made to increase acreage and production. Climatic conditions in St. Francis County are generally consistent with locations in Tennessee where switchgrass rust was previously reported (3). However, northwest Arkansas represents the eastern edge of the southwestern United States, suggesting that P. emaculata may affect switchgrass in geographically diverse areas of the United States. To our knowledge, this study represents the first report of rust on switchgrass in Arkansas. Managing this disease will be an important consideration for large-scale switchgrass cultivation in the state. References: (1) M. Gardes and T. D. Bruns. Mol. Ecol. 2:113, 1993. (2) P. Ramachar and G. Cummins. Mycopathol. Mycol. Appl. 25:7, 1965. (3) J. Zale et al. Plant. Dis. 92:1710, 2008.
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Affiliation(s)
- R L Hirsch
- Department of Plant Pathology, Division of Agriculture, University of Arkansas, Fayetteville 72701
| | - D O TeBeest
- Department of Plant Pathology, Division of Agriculture, University of Arkansas, Fayetteville 72701
| | - B H Bluhm
- Department of Plant Pathology, Division of Agriculture, University of Arkansas, Fayetteville 72701
| | - C P West
- Department of Crop, Soil, and Environmental Science, Division of Agriculture, University of Arkansas, Fayetteville 72701
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12
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Flores R, Coblentz WK, Ogden RK, Coffey KP, Looper ML, West CP, Rosenkrans CF. Effects of fescue type and sampling date on the nitrogen disappearance kinetics of autumn-stockpiled tall fescue. J Dairy Sci 2008; 91:1597-606. [PMID: 18349252 DOI: 10.3168/jds.2007-0787] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Two tall fescue [Lolium arundinaceum (Schreb.) Darbysh] forages, one an experimental host plant/endophyte association containing a novel endophyte that produces low or nil concentrations of ergot alkaloids (HM4) and the other a typical association of Kentucky 31 tall fescue and the wild-type endophyte (Neotyphodium coenophialum; E+), were autumn-stockpiled following late-summer clipping and fertilization with 56 kg/ha of N to assess N partitioning and ruminal disappearance kinetics of N for these autumn-stockpiled tall fescue forages. Beginning on December 4, 2003, sixteen 361 +/- 56.4-kg replacement dairy heifers were stratified by weight and breeding, and assigned to one of four 1.6-ha pastures (2 each of E+ and HM4) that were strip-grazed throughout the winter. Pastures were sampled before grazing was initiated (December 4), each time heifers were allowed access to a fresh pasture strip (December 26, January 15, and February 4), and when the study was terminated (February 26). Generally, fescue type and the fescue type x sampling date interaction exhibited only minor effects on total forage N, or partitioning of N within the cell solubles or the cell wall. For pregrazed forages, concentrations of N and N partitioned within the cell solubles both declined in a strongly linear relationship with sampling dates. In contrast, concentrations of cell-wall-associated N changed in erratic and often higher-ordered relationships with time, but the magnitude of these responses generally was limited. Unlike the partitioning of N within cell-wall and cell-soluble fractions, kinetic characteristics of ruminal N disappearance frequently exhibited interactions of fescue type and sampling date. For pregrazed forages, these included interactions for all response variables, and for postgrazed forages, fractions B and C, as well as rumen degradable protein. Ruminal disappearance rate for pregrazed E+ and HM4 exhibited quadratic (range = 0.057 to 0.082/h) and cubic (range = 0.057 to 0.075/h) relationships with time, respectively. For postgrazed E+ and HM4 forages, ruminal disappearance rate was unaffected (mean = 0.066/h) or only tended to be affected by sampling date (mean = 0.065/h), respectively. Concentrations of rumen degradable protein exhibited various curvilinear relationships with sampling dates, but disappearance was consistently extensive, and the overall range was relatively narrow (71.3 to 78.9% of N). These findings suggest that ruminal disappearance of N for autumn-stockpiled tall fescue forages remains extensive throughout the winter months and is only affected minimally by fescue type, sampling date, and grazing status.
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Affiliation(s)
- R Flores
- Department of Animal Science, University of Arkansas, Fayetteville 72701, USA
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13
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Beck PA, Gunter SA, Lusby KS, West CP, Watkins KB, Hubbell DS. Animal performance and economic comparison of novel and toxic endophyte tall fescues to cool-season annuals. J Anim Sci 2008; 86:2043-55. [PMID: 18310498 DOI: 10.2527/jas.2007-0522] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Increased costs of annual establishment of small grain pasture associated with fuel, machinery, and labor are eroding the profitability of stocker cattle enterprises. Interest has therefore increased in development of cool-season perennial grasses that are persistent and high quality. This study occurred on 24 ha (divided into thirty 0.81-ha paddocks) located at the University of Arkansas Division of Agriculture Livestock and Forestry Branch Station, near Batesville. Two tall fescue (Festuca arundinacea Schreb.) cultivars infected with novel endophytes (NE), Jesup infected with AR542 endophyte (Jesup AR542), and HiMag infected with Number 11 endophyte (HM11) were established in September 2002. Jesup AR542 and HM11 were compared with endemic endophyte Kentucky 31 (KY-31) tall fescue; wheat (Triticum aestivum L.) and cereal rye (WR, Secale cereale L.) planted in September 2003, 2004, and 2005; and annual ryegrass [RG, Lolium perenne L. ssp. multiflorum (Lam.) Husnot] planted in September 2004 and 2005. Each year, 3 steers (3.7 steers/ha) were placed on each pasture for fall and winter grazing, and 5 steers (6.2 steers/ha) were placed on each pasture for spring grazing. Animal performance is presented by year in the presence of a year x treatment interaction (P < 0.01). Body weight gain per hectare of steers grazing NE tall fescue was greater (P < 0.01) than those of KY-31 and WR during 2003 to 2004, whereas in 2004 to 2005, BW gain per hectare of steers grazing NE and RG did not differ (P < or = 0.29) and was greater (P < 0.01) than that of WR, which was greater (P < 0.01) than that of KY-31. During 2005 to 2006, BW gain per hectare was greater (P < 0.01) for steers grazing RG than those of NE and WR, which did not differ (P > or = 0.14). Body weight gain per hectare was least (P < 0.01) for steers grazing KY-31. Average net return of NE tall fescue was greater (P < 0.01) than KY-31, but profitability of NE did not consistently differ from cool-season annuals. Across the 3-yr study, NE tall fescue produced net returns per hectare of $219; this level of profitability would require 4 yr for a new planting of NE tall fescue to break even. Novel endophyte tall fescues offer potential benefits related to decreased risk of stand establishment of annual forage crops, longer growing season, and acceptable animal performance.
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Affiliation(s)
- P A Beck
- Southwest Research and Extension Center, University of Arkansas, Hope 7180, USA.
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14
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Flores R, Coblentz WK, Ogden RK, Coffey KP, Looper ML, West CP, Rosenkrans CF. Effects of Fescue Type and Sampling Date on the Ruminal Disappearance Kinetics of Autumn-Stockpiled Tall Fescue. J Dairy Sci 2007; 90:2883-96. [PMID: 17517728 DOI: 10.3168/jds.2006-726] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [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: 11/19/2022]
Abstract
Two tall fescue (Festuca arundinacea Schreb.) forages, one an experimental host plant/endophyte association containing a novel endophyte (HM4) that produces low or nil concentrations of ergot alkaloids, and the other a typical association of Kentucky 31 tall fescue and the wild-type endophyte (Neotyphodium coenophialum; E+), were autumn-stockpiled following late-summer clipping and fertilization with 56 kg/ha of N to assess the nutritive value and ruminal disappearance kinetics of autumn-stockpiled tall fescue forages. Beginning on December 4, 2003, sixteen 361 +/- 56.4-kg replacement dairy heifers were stratified by weight and breeding and assigned to one of four 1.6-ha pastures (2 each of E+ and HM4) that were strip-grazed throughout the winter. Pastures were sampled before grazing was initiated (December 4), each time heifers were allowed access to a fresh strip (December 26, January 15, and February 4), and when the study was terminated (February 26). For fiber components, there were no interactions between fescue type and sampling date for either pregrazed or postgrazed forages. Over sampling dates, neutral detergent fiber (NDF; 56.5 to 67.8%), acid detergent fiber (27.7 to 34.9%), hemicellulose (28.8 to 34.0%), cellulose (25.0 to 28.1%), and lignin (3.61 to 10.05%) varied with sampling date, but patterns were almost exclusively curvilinear with time. Ruminal disappearance rate of dry matter (DM) was not affected by any treatment factor (overall mean for both pregrazed and postgrazed forages = 0.050 h(- 1)); similar responses were observed for NDF disappearance (overall mean = 0.048 h(- 1)). Interactions of fescue type and sampling date were observed for both pregrazed and postgrazed forages with respect to effective ruminal disappearance of DM; however, estimates were relatively high for all forages (overall mean = 64.0%). Effective disappearance of NDF was relatively extensive for all forages (overall mean = 55.4% of NDF). Based on the results of this trial, the endophyte status of stockpiled tall fescue forages had little practical effect on forage nutritive value and kinetics of ruminal DM or NDF disappearance. Overall, autumn-stockpiled tall fescue forages would appear to be a legitimate and lower cost alternative to harvested forages, and appear to possess suitable nutritional characteristics for developing dairy heifers in the Ozark Highlands.
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Affiliation(s)
- R Flores
- Department of Animal Science, University of Arkansas, Fayetteville 72701, USA
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15
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Nihsen ME, Piper EL, West CP, Crawford RJ, Denard TM, Johnson ZB, Roberts CA, Spiers DA, Rosenkrans CF. Growth rate and physiology of steers grazing tall fescue inoculated with novel endophytes. J Anim Sci 2004; 82:878-83. [PMID: 15032446 DOI: 10.2527/2004.823878x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [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: 11/13/2022] Open
Abstract
Cattle grazing tall fescue (Festuca arundinacea Schreb.) often develop fescue toxicosis. This condition is thought to be caused by ergot alkaloids produced by the endophyte Neotyphodium coenophialum. Endophytes from wild tall fescue plants, which do not produce ergot alkaloids, were transferred into the endophyte-free tall fescue germplasm, HiMag. The novel associations also lacked the ability to produce ergot alkaloids. Our objective was to determine whether cattle grazing these novel endophyte associations showed signs of fescue toxicosis. At the Fayetteville, Arkansas location, tester steers (n = 72) were assigned to one of four pasture treatments: endophyte-free HiMag tall fescue (HiMag-); 'Kentucky-31' tall fescue infected with its native, toxic endophyte (KY+); and two novel endophyte-infected tall fescue associations, HiMag4 and HiMag9. At the Mount Vernon, Missouri location, steers (n = 54) were used to test three of the four cultivars (HiMag9 was not tested). Ergot alkaloid concentrations in the forage of HiMag4 and HiMag9 were low or undetectable. Respiration rate, rectal temperature, ADG, and hair scores were measured during the grazing period. Blood was collected via jugular venipuncture and used for prolactin, aspartate aminotransferase, alkaline phosphatase (ALP), lactate dehydrogenase (LDH), cholesterol, triglyceride, and creatinine analysis. Weight gains by steers grazing HiMag4 and HiMag9 did not differ from those of steers grazing HiMag-, but were greater than gains (P < 0.05) by steers on the KY+ treatment. Steers grazing KY+ had higher (P < 0.05) respiration rates, rectal temperatures, and hair scores than did steers grazing novel endophyte and HiMag- pastures. Prolactin, ALP, cholesterol, LDH, and triglycerides all were suppressed (P < 0.05) in steers grazing KY+ compared with steers grazing novel endophyte and HiMag- pastures. Steers grazing the novel endophyte tall fescues did not suffer from the decreased weight gains and toxicities associated with fescue toxicosis, resulting in enhanced animal production.
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Affiliation(s)
- M E Nihsen
- Department of Animal Science, University of Arkansas, Fayetteville 72701, USA
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16
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Roberts CA, Spiers DE, Karr AL, Benedict HR, Sleper DA, Eichen PA, West CP, Piper EL, Rottinghaus GE. Use of a rat model to evaluate tall fescue seed infected with introduced strains of Neotyphodium coenophialum. J Agric Food Chem 2002; 50:5742-5745. [PMID: 12236708 DOI: 10.1021/jf020336n] [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] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Experimental cultivars of the pasture grass tall fescue are infected with unique strains of the fungal endophyte Neotyphodium coenophialum, which produce low concentrations of ergot alkaloids. A rat model was evaluated as a tool for rapid, initial screening of experimental cultivars considered to be nontoxic. Rats were fed diets that included seed from experimental cultivars of tall fescue with introduced strains of N. coenophialum and a toxic control diet containing seed of the cultivar Kentucky 31 (KY31), with its endemic strain of N. coenophialum. Rats were preconditioned to a nontoxic diet and then fed treatment diets for 13 days with 5 days at thermoneutrality (21 degrees C) followed by 8 days under heat stress (31 degrees C). For most of the 13-day treatment period, rats fed KY31 exhibited depressed daily intake compared to those fed diets of cultivars with introduced endophytes (P < 0.05). In addition, rats fed KY31 exhibited significantly less weight than rats on other diets after heat treatment was imposed. For all initial trials and repeated trials, total intake and total gain calculated at the end of each trial were the most consistent indicators of toxicity.
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Affiliation(s)
- C A Roberts
- University of Missouri, Columbia 65211, USA.
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17
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Hassaballa H, Gorelick PB, West CP, Hansen MD, Adams HP. Ischemic stroke outcome: racial differences in the trial of danaparoid in acute stroke (TOAST). Neurology 2001; 57:691-7. [PMID: 11524481 DOI: 10.1212/wnl.57.4.691] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [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: 11/15/2022] Open
Abstract
OBJECTIVE To determine racial differences in baseline stroke risk factors and other measures in the Trial of ORG 10172 in Acute Stroke Therapy (TOAST). Differences in these factors could influence response to acute stroke therapy and overall stroke outcome. METHODS The authors compared baseline demographic, medical, stroke, physical examination, CT, laboratory, and neurologic factors among 292 African-American and 801 white patients who enrolled in the TOAST study. TOAST compared danaparoid (ORG 10172) with placebo among acute ischemic stroke patients who were treated within 24 hours of stroke onset. RESULTS African-Americans were younger and more frequently had hypertension, diabetes mellitus, congestive heart failure, and prior strokes. In addition, African-Americans had higher mean diastolic blood pressure, more lacunar strokes, and more severe prestroke disability. There were no significant differences between African-Americans and white patients in outcomes at 7 days, overall number of adverse experiences, or occurrence of serious bleeds or hemorrhagic transformations. However, there was a trend toward a higher rate of favorable outcomes in white patients at 7 days. There was no significant difference in very favorable outcome at 3 months between African-American and white patients, but significantly more white patients had favorable outcome at 3 months. CONCLUSION Although African-Americans possess a number of factors that should predict higher rates of poor stroke outcome after acute therapy, they have the capacity to respond similarly to white patients after acute stroke therapy. Perhaps younger age and presence of lacunar infarction are stronger predictors of good outcomes than was appreciated previously.
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Affiliation(s)
- H Hassaballa
- Department of Internal Medicine, Rush Presbyterian St. Luke's Medical Center, Chicago, IL 60612, USA.
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18
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Abstract
EIAs for IgG and IgM antibodies directed against Ebola (EBO) viral antigens have been developed and evaluated using sera of animals and humans surviving infection with EBO viruses. The IgM capture assay detected anti-EBO (subtype Reston) antibodies in the sera of 5 of 5 experimentally infected animals at the time they succumbed to lethal infections. IgM antibodies were also detected in the serum of a human who was infected with EBO (subtype Reston) during a postmortem examination of an infected monkey. The antibody was detectable as early as day 6 after infection in experimentally infected animals and persisted for <90 days. The IgG response was less rapid; however, it persisted for >400 days in 3 animals who survived infection, and it persisted for approximately 10 years after infection in the sera of 2 humans. Although these data are limited by the number of sera available for verification, the IgM assay seems to have great promise as a diagnostic tool. Furthermore the long-term persistence of the IgG antibodies measured by this test strongly suggests that the ELISA will be useful in field investigations of EBO virus.
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Affiliation(s)
- T G Ksiazek
- Disease Assessment Division, US Army Medical Research Institute of Infectious Disease, Fort Detrick, Frederick, Maryland, USA
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19
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Abstract
Hysterectomy provides definitive treatment for uterine fibroids. Surgery should be offered to women whose fibroids are symptomatic; it is not indicated on the basis of uterine size alone. Myomectomy is an option for those wishing to preserve uterine function. The prospects for successful pregnancy following myomectomy are encouraging, although there is a significant risk of the later recurrence of fibroids. Laparotomy remains the most appropriate surgical approach for large fibroids, although vaginal, rather than abdominal, hysterectomy may be suitable for some women whose uteri do not exceed a 12-14 week gestation size. There is some evidence that the morbidity of abdominal procedures increases with very large uteri. Uterine shrinkage with GnRH analogues may facilitate vaginal hysterectomy and be useful prior to abdominal hysterectomy or myomectomy for very large fibroids, although cost-effectiveness for its use with abdominal procedures has not been demonstrated.
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Affiliation(s)
- C P West
- Department of Obstetrics & Gynaecology, University of Edinburgh, UK
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Ely JW, Goerdt CJ, Bergus GR, West CP, Dawson JD, Doebbeling BN. The effect of physician characteristics on compliance with adult preventive care guidelines. Fam Med 1998; 30:34-9. [PMID: 9460614] [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: 02/06/2023]
Abstract
BACKGROUND AND OBJECTIVES This study identified physician characteristics and attitudes related to self-reported compliance with adult prevention guidelines. METHODS A questionnaire was mailed to family practice and internal medicine residents and faculty at the University of Iowa (n = 209). The questionnaire's 78 items fell into seven categories, including physician demographics, history-taking practices, counseling practices, self-perceived effectiveness in changing patient behavior, beliefs about preventive care, knowledge about preventive care, and perceived barriers to the delivery of preventive care. RESULTS Compliance with history-taking recommendations was independently associated with high knowledge scores, female physician gender, and high self-perceived effectiveness in changing patient behavior. The only factor that was independently associated with counseling efforts was self-perceived effectiveness in changing patient behavior. CONCLUSIONS Factors that were independently associated with self-reported preventive care efforts include female physician gender, knowledge about preventive care guidelines, and perceived effectiveness in changing patient behavior. After controlling for these factors, other variables such as lack of time, lack of reminder systems, attitudes about preventive care, and amount of formal preventive care education were not related to self-reported compliance with counseling and history-taking recommendations.
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Affiliation(s)
- J W Ely
- Department of Family Medicine, University of Iowa, Iowa City, USA.
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Caird LE, West CP, Lumsden MA, Hannan WJ, Gow SM. Medroxyprogesterone acetate with Zoladex for long-term treatment of fibroids: effects on bone density and patient acceptability. Hum Reprod 1997; 12:436-40. [PMID: 9130735 DOI: 10.1093/humrep/12.3.436] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [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: 02/04/2023] Open
Abstract
A randomized trial was carried out to investigate the effect of 12 months administration of the gonadotrophin-releasing hormone agonist (GnRHa) Zoladex in combination with either placebo or medroxyprogesterone acetate (MPA) from the third month. Bone density, markers of bone resorption, symptoms and uterine volume were monitored in 24 women with symptomatic fibroids or menstrual problems. A total of 21 women were recruited to act as controls for the assessment of bone parameters. Vasomotor side-effects were reduced significantly in the MPA-treated group. The reduction in uterine volume in women with fibroids was not impaired by the addition of MPA. The bone markers osteocalcin and alkaline phosphatase were assessed in plasma, and the cross-links pyridinoline and deoxypyridinoline measured in urine. Changes in these markers are reported which suggest increases in bone resorption during the period of observation. Bone mineral density (BMD) was assessed by dual energy X-ray absorptiometry at the spine and forearm. The net reduction in BMD at the spine in the treated groups was 4.30 +/- 0.59% at 6 months and 7.50 +/- 0.78% at 1 year, with no change in the control group. No change was seen in forearm BMD. No protective effect was observed when MPA was added. At 1 year after the completion of treatment, BMD remained significantly below baseline, and this has implications for the prolonged use of GnRHa.
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Affiliation(s)
- L E Caird
- Department of Obstetrics and Gynaecology, University of Edinburgh, Centre for Reproductive Biology, UK
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22
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Roberts RN, Norman BP, Harrison CG, Heaton NR, Law JK, Wadehra V, Younger HM, West CP. A medical audit and patient survey of hysterectomies performed for menstrual disorders. Scott Med J 1996; 41:44-6. [PMID: 8735501 DOI: 10.1177/003693309604100204] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [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: 02/01/2023]
Abstract
The aim of the study was to carry out an audit of 283 hysterectomies performed for menstrual disorders over a one year period, and to determine the satisfaction of the women concerned towards their treatment. The medical records of these patients were examined, and they were each sent a questionnaire, 69% of which were completed and returned. The most common presenting symptoms were menorrhagia and dysmenorrhoea. In 53% of cases no clinical abnormality was postulated and in 31% of cases no pathological abnormality was found. The preoperative clinical and pathological diagnoses were in agreement for 59% of patients. Over 90% of women were satisfied with the management of their case by their GP and the gynaecology outpatient clinic. The use of patient-controlled analgesia systems was associated with better post-operative pain relief than intramuscular injections. Thirteen percent of patients required blood transfusion; 21% suffered some form of postoperative complication, most of which were minor. Ninety-four percent of the women were pleased that they had undergone hysterectomy, and 76% wished that they had had the operation sooner. It was concluded that hysterectomy is perceived positively by patients and should not necessarily be considered as a last resort treatment for menstrual disorders.
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Affiliation(s)
- R N Roberts
- Department of Obstetrics and Gynaecology, University of Edinburgh
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Abstract
Presence of the endophytic; fungus Acremonium coenophialum Morgan-Jones and Gams in tall fescue (Festuca artuidinacea- Sehreb.) enhances host persistence in drought-prone environments. However, the physiological mechanism is not well understood. We investigated the influence of endophyte infection and water deficit on osmotic adjustment, stomatal conductance, tiller survival and leaf elongation rate of genotype GA87-122 and cv. Kentucky-31 (KY31) of tall fescue. Plants were grown in a greenhouse in pots containing fine-silty topsoil (experiment 1) or sand (experiment 2). In expt 1, endophyte-infected (EI) and endophyte-free (EF) isolines of GA87-122 were exposed to two drought preconditioning cycles, after which all pots were re-watered and osmotic adjustment determined. Osmotic adjustment was -0.46 and -0.51 MPa in El leaf blades and tiller bases and -0.29 and -0.13 MPa in EF leaf blades and tiller bases, respectively. In expt 2, EI and EF GA87-122 and KY31 Mere exposed to severe drought after two preconditioning cycles, then re-watered. During the second preconditioning drying cycle of KY31, stomatal conductance tended to be lower in EI than in EF plants, but the difference was significant (P⩽ 0-05) only at two sampling times. Shoot tissues osmotically adjusted 0.17-0.31 MPa more in EI than in EF plants. Tiller survival and leaf elongation rates were higher (P⩽ 0.05) in preconditioned EI than in EF plants. Basal-zone osmotic adjustment was correlated with tiller survival rate in GA87-122 and KY31 (r = 0.87, P⩽ 0.01 for both). Enhanced osmotic adjustment in the meristematic and growing zone might account far improved survival of tillers by facilitating protection of the apical meristem.
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Affiliation(s)
- A A Elmi
- Agricultural Research Station, Virginia State Univ., Petersburg, VA 23806, USA
| | - C P West
- Department of Agronomy, 276 Altheimer Dr., University of Arkansas, Fayetteville, AR 72704, USA
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West CP, Hillier H. Ovarian suppression with the gonadotrophin-releasing hormone agonist goserelin (Zoladex) in management of the premenstrual tension syndrome. Hum Reprod 1994; 9:1058-63. [PMID: 7962376 DOI: 10.1093/oxfordjournals.humrep.a138633] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [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: 01/28/2023] Open
Abstract
The objective of this study was to determine the effectiveness of ovarian suppression by a GnRH agonist analogue in 32 women with prospectively confirmed severe premenstrual tension. The design was a randomized, double-blind study comparing goserelin 3.6 mg with placebo, both given as a monthly s.c. injection for 3 months. Self-assessment was by daily visual analogue scales (VAS) for anxiety and depression, daily quantitative symptom rating for breast discomfort, swelling, irritability, tension, depression and by monthly Hospital Anxiety and Depression (HAD) scales. Of the 16 women in each group, 15 completed active and 12 completed placebo therapy. Median symptom scores for whole cycles showed a significant reduction of breast discomfort and swelling during active treatment, with no significant improvement in psychological symptoms. Analysis by cycle phase showed that for individual subjects, pre-treatment differences in VAS scores for anxiety and depression were abolished in a significantly greater proportion of actively treated cycles. Within-group comparisons showed a marked placebo effect and, comparing the two groups, differences reached significance only during treatment cycle 1 and the first post-treatment cycle for anxiety with no significant differences for depression. It was concluded that while suppression of ovarian activity with a gonadotrophin-releasing hormone analogue dampens down cyclical mood swings, it has a more marked effect on the physical components of the premenstrual syndrome. Results reconfirm the positive role of placebo in the management of this condition.
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Affiliation(s)
- C P West
- Department of Obstetrics and Gynaecology, University of Edinburgh, UK
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Lumsden MA, West CP, Thomas E, Coutts J, Hillier H, Thomas N, Baird DT. Treatment with the gonadotrophin releasing hormone-agonist goserelin before hysterectomy for uterine fibroids. Br J Obstet Gynaecol 1994; 101:438-42. [PMID: 8018618 DOI: 10.1111/j.1471-0528.1994.tb11919.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVE To investigate the effect of the gonadotrophin releasing hormone (GnRH)-agonist goserelin, given by monthly subcutaneous injection for three months prior to total abdominal hysterectomy for uterine leiomyomata, on the pre-operative symptoms, difficulty of operation and operative blood loss. DESIGN Randomised placebo-controlled study. SETTING Patients were recruited from the gynaecological outpatient departments from hospitals in Edinburgh, Glasgow and Newcastle. SUBJECTS Seventy-one premenopausal women with uterine leiomyomata who were on the waiting list for hysterectomy. INTERVENTIONS After the presence of leiomyomata was confirmed using ultrasonography, the women were randomised to receive either the GnRH-agonist goserelin by monthly subcutaneous injection or a sham injection for three months prior to operation. At the monthly visits, patients were asked about treatment related symptoms, fibroid related symptoms, and their bleeding patterns. Blood was taken for haematological assessment. MAIN OUTCOME MEASURES Haemoglobin concentrations at recruitment, at operation and post-operatively, pre-operative symptoms, operative difficulty and blood loss and post-operative complications. RESULTS Treatment with goserelin induced amenorrhoea in over 80% of the women, and this was associated with a significant rise in haemoglobin level. At the time of operation, fibroid related symptoms were less in the goserelin group than in the placebo group. The hysterectomy was technically easier and the median (range) operative blood loss was significantly lower in the goserelin group compared with the placebo group (187 (60-600) ml vs 308 (118-1000) ml respectively; P < 0.05, Wilcoxon signed rank test). There was no difference between the two groups in the duration of hospital stay or the frequency of post-operative complications. The fibroids were smaller at the time of operation in the goserelin group, and more women treated with goserelin were able to have their operations through a transverse incision. CONCLUSIONS This study demonstrates the benefits of goserelin in women having total abdominal hysterectomy for uterine leiomyomata.
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Affiliation(s)
- M A Lumsden
- Department of Obstetrics and Gynaecology, University of Edinburgh, UK
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26
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Abstract
Epignathi are unusual congenital tumours presenting as oropharyngeal masses, often resulting in rapid asphyxia following birth. Occasionally, intracranial extension of the tumour is present, and two such cases are described. The presence of this complication, diagnosable by ultrasound examination, indicates that aggressive surgical treatment is inappropriate.
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Affiliation(s)
- N M Smith
- Department of Paediatric, Pathology and Cytogenetics, Royal Hospital for Sick Children, Edinburgh, U.K
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Zikopoulos K, West CP, Thong PW, Kacser EM, Morrison J, Wu FC. Homologous intra-uterine insemination has no advantage over timed natural intercourse when used in combination with ovulation induction for the treatment of unexplained infertility. Hum Reprod 1993; 8:563-7. [PMID: 8501186 DOI: 10.1093/oxfordjournals.humrep.a138096] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [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: 01/31/2023] Open
Abstract
The objective was to evaluate the role of homologous intrauterine insemination compared with timed natural intercourse, both combined with ovulation induction, in the management of unexplained infertility. A total of 48 couples presenting at a large teaching hospital infertility clinic with unexplained infertility of at least 3 years duration comprised the main study group, and 36 couples with identical entry criteria but under the care of another clinician made up a parallel control group. A randomized design of treatment cycles with within-group and between-group controls was used. Couples in the main study group were treated with either homologous intra-uterine insemination or timed natural intercourse in gonadotrophin-releasing hormone analogue down-regulated cycles, in which ovulation was induced with human menopausal gonadotrophin and human chorionic gonadotrophin. Alternate cycles were monitored to enable optimum timing of natural intercourse provided within-group controls. Couples in the control group underwent timed homologous intravaginal artificial insemination. Cycle fecundity and pregnancy outcome in treated and control groups were monitored. Cycle fecundity of 0.11 in 85 ovulation-induced cycles was significantly higher than 0.02 in 62 within-group and 0.01 in 103 between-group control cycles. There was no difference in conception rates between homologous intra-uterine insemination and timed natural intercourse cycles with ovulation induction. Of the 11 established pregnancies in the ovulation induced group, nine delivered healthy babies (five singleton, three twin, one triplet) and two were ectopic. Results confirmed the value of active management for couples with long-standing unexplained infertility but failed to demonstrate any advantage of homologous intra-uterine insemination over ovulation induction alone.
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Affiliation(s)
- K Zikopoulos
- MRC Reproductive Biology Unit, University of Edinburgh Centre For Reproductive Biology, UK
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28
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Goetsch AL, Galloway DL, Forster LA, Murphy GE, Grant EW, Sun W, Patil A, West CP. Effects of various supplements on voluntary intake and performance by growing cattle consuming forage moderate to high in crude protein. Arch Tierernahr 1993; 44:163-74. [PMID: 8215890 DOI: 10.1080/17450399309386066] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Growing cattle were supplemented with substances to lessen or increase ruminal ammonia level to determine if consumption of moderate- to high-crude protein (CP) forage is limited by high ruminal ammonia absorption. In Experiment 1 (5 x 5 Latin square), five Holstein steers (198 kg) had ad libitum access to alfalfa cubes (17% CP) without supplementation or with corn at 0.25 or 0.75% body weight (BW) alone (LC or HC) or with 0.06% BW of zeolite (chabazite; LC-Z and HC-Z). Total daily organic water (OM) intake was not affected by treatment (6.08, 6.14, 6.11, 6.19 and 6.09 kg for control, LC, LC-Z, HC and HC-Z, respectively; SE 0.25). In Experiment 2, Simmental crossbred beef calves grazed fescue-clover paddocks in the spring (clipped forage: 21 to 27% CP) for 84 days and were supplemented with 0.25 or 0.75% BW corn alone or with added zeolite (0.06% BW) or lasalocid (0.5 mg/kg BW). Daily gain did not differ among treatments (1.24 to 1.31 kg/day). In Experiment 3 (6 x 6 Latin square), six Holstein steer calves (168 kg) had ad libitum access to medium-quality, orchardgrass-clover hay (15% CP). Steers received one of the following six treatments: no supplement (Control), 0.35% BW ground corn (C), corn plus 0.049% BW urea (C-U), 0.35% BW soybean meal (S), 0.205% BW feather meal (F) or 0.103% BW feather meal, 0.052% BW blood meal and 0.067% BW corn gluten meal (F-BG). Total daily OM intake was 5.00, 5.14, 5.00, 5.11, 4.84 and 4.70 kg for control, C, C-U, S, F and F-BG, respectively (SE 0.13). In Experiment 4 (6 x 6 Latin square), six Holstein steer calves (226 kg) were fed 0.75% BW of alfalfa cubes (19% CP) plus ad libitum access to medium- to high-quality orchardgrass hay (16% CP). Steers received one of the following six treatments: no supplement (Control), corn at 0.25% BW alone (c) or mixed with 0.12% BW peanut skins (C-PSK), a mix of high-CP feedstuffs high in ruminal escape protein (0.029% BW blood meal, 0.038% BW corn gluten meal and 0.028% BW feather meal; C-REP), 0.139% soybean meal (C-S) or soybean meal plus peanut skins (C-PSK-S). Total daily OM intake was 6.16, 6.25, 6.13, 6.52, 6.50 and 6.60 kg for control, C, C-PSK, C-REP, C-S and C-PSK-S, respectively (SE 0.10).(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- A L Goetsch
- Dept. of Animal and Poultry Sciences, University of Arkansas Fayetteville 72701
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West CP, Lumsden MA, Hillier H, Sweeting V, Baird DT. Potential role for medroxyprogesterone acetate as an adjunct to goserelin (Zoladex) in the medical management of uterine fibroids. Hum Reprod 1992; 7:328-32. [PMID: 1534089 DOI: 10.1093/oxfordjournals.humrep.a137643] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [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: 12/27/2022] Open
Abstract
Twenty women with symptomatic uterine fibroids were treated with the luteinizing hormone-releasing hormone (LHRH) agonist goserelin (Zoladex) combined with medroxyprogesterone acetate (MPA) in an open pilot study comparing two protocols. Ten women received goserelin 3.6 mg monthly combined with oral MPA 15 mg daily for 6 months. The mean uterine volume (497 cm3) measured by ultrasound fell by only 18% after 3 months, with no further reduction at 6 months. The other 10 women received goserelin alone for the initial 3 months, followed by combined treatment for 3 months. The mean uterine volume (557 cm3) fell by 39% after 3 months with no significant regrowth by 6 months. At 6 months post-treatment, uterine volume had not returned to pretreatment size. MPA significantly reduced the frequency of vasomotor side-effects. There were no differences in plasma oestradiol, luteinizing hormone or follicle stimulating hormone concentrations between the protocols and good symptomatic relief was experienced by both groups. Two years after completion, three women in each group have requested surgical treatment. The results indicate that MPA may be a useful adjunct to LHRH analogues in women with fibroids, reducing side-effects and possibly prolonging the response, although positive effects on bone density have yet to be confirmed. The optimum regimen of administration remains to be clarified as the clinical results were the same with both protocols.
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Affiliation(s)
- C P West
- Department of Obstetrics and Gynaecology, University of Edinburgh, UK
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30
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Affiliation(s)
- C P West
- Department of Obstetrics and Gynaecology, University of Edinburgh, UK
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31
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Goetsch AL, Murphy GE, Grant EW, Forster LA, Galloway DL, West CP, Johnson ZB. Effects of animal and supplement characteristics on average daily gain of grazing beef cattle. J Anim Sci 1991; 69:433-42. [PMID: 2016173 DOI: 10.2527/1991.692433x] [Citation(s) in RCA: 13] [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] [Indexed: 12/29/2022] Open
Abstract
Effects of animal gender and age, use of a growth stimulant, and supplementation with grain alone or grain plus other substances on ADG by growing beef cattle grazing bermudagrass paddocks with sod-seeded rye, wheat, and ryegrass were determined. Two grazing experiments (Exp. 1: late winter through mid-spring; Exp. 2: late spring through mid-summer) were conducted. Experiment 1 used 96, 12- to 13-mo-old Simmental-cross calves (heifers, 240 kg; steers, 272 kg), half of which were implanted with zeranol. Within each implant treatment, cattle received no supplement or .5% BW (DM) of ground corn alone or plus a mix of protein meals, zinc sulfate, thiamin-HCl, or salt. Daily gain was higher (P less than .05) with than without supplementation and was similar (P greater than .10) among supplement treatments. In Exp. 2, 96 crossbred beef steers, approximately 7 (230 kg) or 15 mo old (250 kg), were not supplemented (control) or received .5% BW (DM) of ground corn on d 1 to 84 (C-C), corn plus a protein meal mix on d 1 to 84 (CP-CP), corn on d 43 to 84 (O-C), corn plus the protein meal mix on d 43 to 84 (O-CP), or corn on d 1 to 42 and corn plus the protein meal mix on d 43 to 84 (C-CP). Daily gain on d 1 to 84 was affected (P less than .05) by supplement, age, implant, and the supplement x implant interaction (nonimplanted: .37, .56, .68, .40, .49, and .49; implanted: .37, .62, .54, .49, .70, and .71 kg for control, C-C, CP-CP, O-C, O-CP, and C-CP, respectively).
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Affiliation(s)
- A L Goetsch
- Dept. of Anim. and Poult. Sci., University of Arkansas, Fayetteville 72701
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32
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Affiliation(s)
- C P West
- University of Edinburgh Centre for Reproductive Biology
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33
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Abstract
Forty-eight women with premenstrual problems were recruited for therapy with either medroxyprogesterone (MPA) or norethisterone (NET), both compared with placebo, in a double-blind cross-over study. Thirty-five (73%) completed the study. At an oral dose of 15 mg daily for 21 days each cycle, both MPA and NET suppressed ovulation, although reduction of urinary total oestrogen excretion was significantly greater with NET. Breakthrough bleeding occurred in 74% of the cycles treated with MPA but only in 22% of those with NET. Symptoms were monitored daily by visual analogue scales. Both progestins significantly reduced breast discomfort, compared with placebo. While MPA significantly improved individual psychological symptom scores by the second active treatment cycle and pooled psychological symptom scores in both active cycles, NET was no more effective than the placebo. Similar numbers from both groups withdrew because of adverse effects. Among the women treated with MPA, the response to active and placebo therapy was related to the pretreatment psychological symptom profile. The results suggest that the beneficial effect of therapy with MPA in women with premenstrual problems was a consequence of disruption of menstrual cyclicity rather than a result of ovulation suppression.
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Affiliation(s)
- C P West
- Department of Obstetrics and Gynaecology, University of Edinburgh, Scotland
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Lumsden MA, West CP, Hillier H, Baird DT. Estrogenic action of tamoxifen in women treated with luteinizing hormone-releasing hormone agonists (goserelin)--lack of shrinkage of uterine fibroids. Fertil Steril 1989; 52:924-9. [PMID: 2531684 DOI: 10.1016/s0015-0282(16)53153-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [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: 01/01/2023]
Abstract
Six premenopausal women with uterine fibroids were treated with a combination of tamoxifen, 20 mg/d, and goserelin, 3.6 mg every 28 days, for a total of 24 weeks. Results were compared with those from six women, matched for pretreatment uterine volume, who had been treated with goserelin alone. During combined therapy, plasma and urinary estrogen concentrations were significantly lower than during goserelin alone, whereas sex hormone binding globulin concentrations were significantly higher. Plasma luteinizing hormone and follicle stimulating hormone (FSH) concentrations were both suppressed, in contrast with results during goserelin alone when FSH levels remained within the pretreatment range. None of the women on combined therapy bled in response to the endocrine changes of the initial treatment cycle. Despite this profound pituitary-ovarian suppression, there was no significant change in uterine volume during combined therapy. These results suggest that tamoxifen is acting as an estrogen agonist in women rendered hypoestrogenic with luteinizing hormone-releasing hormone agonists.
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Affiliation(s)
- M A Lumsden
- Department of Obstetrics and Gynaecology, University of Edinburgh, Scotland
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35
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Abstract
Tamoxifen (20 mg per day) was administered for at least 3 months to six premenopausal women with uterine fibromyomata. In all the women there was an increased variability in the length of the menstrual and ovarian cycle associated with a significant lengthening of the luteal phase (16.9 +/- 3.5 vs 12.5 +/- 1.5 days, mean +/- SD, P less than 0.02). The concentration of oestradiol and progesterone in plasma and their metabolites in urine (oestrone glucuronide and pregnanediol) increased reflecting multiple follicular development and ovulation. There was a significant rise in the concentration of FSH during the luteal phase of the cycle (8.0 +/- 2.9 vs 2.0 +/- 1.7 U/l, P less than 0.01). There was no change in the size of the uterine leiomyomata. These results demonstrate that the antioestrogen tamoxifen results in an increased secretion of gonadotrophins by antagonizing the effects of oestradiol at the hypothalamus and anterior pituitary. The lengthening of the luteal phase suggests oestradiol may play a role in the mechanism of luteal regression either locally or via feedback effect on gonadotrophins.
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Affiliation(s)
- M A Lumsden
- Department of Obstetrics and Gynaecology, University of Edinburgh, UK
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36
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Abstract
Fibroids are an important cause of menorrhagia, resistant to conventional methods of medical treatment. The mechanism of their effect on menstrual blood loss is poorly understood but may involve abnormalities of local venous drainage, enlargement of the uterine cavity and abnormalities in prostaglandin production. Their cause remains unknown although it has long been assumed that they are oestrogen-dependent. In the past, study of their aetiology, prevention and treatment has received scant attention. Recent developments including measurement of tissue receptors for steroids and growth factors, non-invasive methods of monitoring fibroid growth and the use of LHRH agonists have enabled further study of their nature and of their response to therapy although much work remains to be done. The majority of women with uterine fibroids associated with menorrhagia are treated by hysterectomy although developments in endoscopic surgery have enabled a more conservative approach in some circumstances. LHRH agonists are the only medical agents which cause substantial shrinkage of fibroids although regression is not permanent. These agents are of value in short-term relief of symptoms and are likely to be a useful adjunct to surgery by reducing both uterine volume and bloodflow. However, because of the consequences of prolonged ovarian suppression, they are not suitable for long-term use unless there are medical contraindications to surgery. It remains to be seen whether their use in low-dose regimens or in combination with other agents will provide a successful, safe and cost-effective alternative to hysterectomy in women whose primary problem is heavy menstrual loss. They do however offer a means of conserving reproductive function in women wishing to retain this option.
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Lumsden MA, West CP, Hawkins RA, Bramley TA, Rumgay L, Baird DT. The binding of steroids to myometrium and leiomyomata (fibroids) in women treated with the gonadotrophin-releasing hormone agonist Zoladex (ICI 118630). J Endocrinol 1989; 121:389-96. [PMID: 2526844 DOI: 10.1677/joe.0.1210389] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Since uterine leiomyomata (fibroids) are not found in conditions where oestradiol is either absent or present only in low concentrations, oestradiol is considered to be an important factor in the control of fibroid growth. To investigate whether this is due to a direct effect on the tissue, oestradiol and progestogen receptors were measured in tissue removed at hysterectomy from 12 normally cycling women and 13 women who had received the gonadotrophin-releasing hormone (GnRH) agonist Zoladex (ICI 118630) as a subcutaneous depot given at monthly intervals for 3 months preoperatively and a third group of three women who had received the antioestrogen tamoxifen (20 mg daily) for 3 months before surgery. Both unoccupied oestradiol receptors (measured by separating bound from free hormone with dextran-coated charcoal; DCC) and 'total' receptor populations (as measured by an enzyme immunoassay) were measured in each fibroid and adjoining myometrium. There was significantly more binding of both oestradiol and progestogen to fibroid than to myometrium in both the control (P less than 0.01) and agonist-treated groups (P less than 0.05). Oestradiol binding to fibroids in women treated with Zoladex exceeded that in the normally cycling women (P less than 0.05) which in turn exceeded that in the tamoxifen-treated group (P less than 0.05). However, the binding of progestogen, measured by DCC showed the reverse trend. These results may be explained by the low circulating oestradiol concentration in the GnRH agonist-treated women leading to low receptor occupancy.
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Affiliation(s)
- M A Lumsden
- Department of Obstetrics and Gynaecology, University of Edinburgh
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Baird DT, Bramley TA, Hawkins TA, Lumsden MA, West CP. Effect of treatment with LHRH analogue Zoladex on binding of oestradiol, progesterone and epidermal growth factor to uterine fibromyomata. Horm Res 1989; 32 Suppl 1:154-6. [PMID: 2533146 DOI: 10.1159/000181333] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Treatment of patients with fibromyomata by Zoladex produces suppression of ovarian function. Receptor changes also occur in fibroids of women treated with Zoladex. The concentration of oestradiol receptors is significantly higher, whilst that of epidermal growth factor and progesterone is significantly lower.
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Affiliation(s)
- D T Baird
- Department of Obstetrics and Gynaecology, University of Edinburgh, Centre for Reproductive Biology, UK
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Abstract
Improved diagnosis has made drug treatment of uterine fibroids more of a reality. For long-term use, conclusions cannot yet be drawn on the merits of LHRH analogues administered alone or in sequence with other agents. However, such treatment enables preservation of reproductive function, whilst avoiding potential sequelae of surgical myomectomy.
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Affiliation(s)
- C P West
- Department of Obstetrics and Gyneacology, University of Edinburgh, UK
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40
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Abstract
100 women consecutively referred to a gynaecological clinic with premenstrual problems were prospectively assessed by daily completion of a set of visual analogue scales (VAS). The relationship of their symptoms to menstrual cycle phase was quantified by calculating the percentage change in symptom intensity between the premenstrual week and the postmenstrual week and also during menstruation itself. The results indicated that the physical symptoms of breast discomfort and swelling were more closely related to menstrual cycle phase than were the psychological symptoms of tension, irritability or lethargy and depression. Only 32 of the women showed reduction of the premenstrual psychological symptoms by 75% or more during the postmenstrual week, while the corresponding degree of physical symptom relief was recorded by 62 women. For almost half the women, adverse mental symptoms reached their peak after the onset of menstrual bleeding. Significantly fewer of the women with almost total (75% or more) relief of their psychological symptoms postmenstrually had a history of psychiatric treatment, marital breakdown, or more than three children, compared with those whose symptoms were less completely relieved. The results suggest that a large proportion of women who experience premenstrual symptoms suffer a premenstrual and/or menstrual exacerbation of problems which are present throughout the cycle and are therefore unlikely to respond to hormonal manipulation.
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Affiliation(s)
- C P West
- Department of Obstetrics and Gynaecology, University of Edinburgh, Scotland
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Lumsden MA, West CP, Bramley T, Rumgay L, Baird DT. The binding of epidermal growth factor to the human uterus and leiomyomata in women rendered hypo-oestrogenic by continuous administration of an LHRH agonist. Br J Obstet Gynaecol 1988; 95:1299-304. [PMID: 2975953 DOI: 10.1111/j.1471-0528.1988.tb06821.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The binding of epidermal growth factor (EGF) to human myometrium and leiomyomata was assessed in a group of women rendered hypo-oestrogenic with the LHRH agonist Zoladex (ICI 118630). The results were compared with those obtained with tissues from women with normal cycles. In normal women, the specific binding of radiolabelled [125I] EGF to both myometrial and fibroid homogenates did not vary during the menstrual cycle, but the specific binding of [125I] EGF to fibroid in women treated with LHRH agonist was significantly less than in the untreated group. Since the hypo-oestrogenic state induced by the agonist is associated with a decrease in fibroid size, the results suggest that the effect of oestrogen on fibroid tissue may partly be mediated by EGF.
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Affiliation(s)
- M A Lumsden
- Department of Obstetrics and Gynaecology, University of Edinburgh
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West CP. LHRH analogues in the management of uterine fibroids, premenstrual syndrome and breast malignancies. Baillieres Clin Obstet Gynaecol 1988; 2:689-709. [PMID: 3069270 DOI: 10.1016/s0950-3552(88)80053-1] [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] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Agonist analogues of LHRH are of potential value in the management of oestrogen-dependent conditions in women. However, their clinical effectiveness is a direct consequence of ovarian suppression which is in itself associated with adverse effects, in particular loss of bone mass. They are thus unsuitable for long-term use in premenopausal women with benign conditions but in future may have a wider role in combination with other agents. In women with uterine fibroids, therapy leads to reduction of uterine volume and alleviation of symptoms although the benefit is rapidly reversed when therapy ceases. Although there is a theoretical potential for combined therapy, successful combinations have yet to be identified. Thus, at the present time, agonists of LHRH do not offer a true alternative to surgery for the majority of women. They will be of value where there is a contra-indication to surgery and for women approaching the age of the natural menopause. They may also be of use prior to surgery, both in controlling symptoms and in reducing surgical morbidity and blood loss. LHRH agonists appear to be beneficial in the management of some women with severe premenstrual tension but intensify symptoms in others. Particular care is required in selection of women for such therapy because of the uncertain nature of the condition and its high rate of response to placebo therapy. Response is dependent on the degree of ovarian suppression and long-term use of LHRH agonists alone is clearly undesirable. However LHRH agonists alone or in combination with ovarian steroids are of potential value as a research tool. In premenopausal women with advanced breast cancer, concerns about the long-term effects of therapy with LHRH agonists are less important and these drugs offer a medical alternative to oophorectomy as first-line treatment in women with oestrogen receptor-positive tumours. Future developments are likely to include evaluation of combined therapy and comparative studies in women with early disease. As such studies involve long-term treatment, they will generate very useful information about the effects of therapy. This will be of great value to clinicians evaluating the role of LHRH agonists in the management of benign conditions.
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Affiliation(s)
- D T Baird
- Department of Obstetrics and Gynaecology, University of Edinburgh
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Herring AJ, Anderson IE, McClenaghan M, Inglis NF, Williams H, Matheson BA, West CP, Rodger M, Brettle PP. Restriction endonuclease analysis of DNA from two isolates of Chlamydia psittaci obtained from human abortions. Br Med J (Clin Res Ed) 1987; 295:1239. [PMID: 2825905 PMCID: PMC1248310 DOI: 10.1136/bmj.295.6608.1239] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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West CP, Lumsden MA, Lawson S, Williamson J, Baird DT. Shrinkage of uterine fibroids during therapy with goserelin (Zoladex): a luteinizing hormone-releasing hormone agonist administered as a monthly subcutaneous depot. Fertil Steril 1987; 48:45-51. [PMID: 2954863 DOI: 10.1016/s0015-0282(16)59288-7] [Citation(s) in RCA: 120] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Thirteen premenopausal women with uterine fibroids were treated for a maximum of 6 months with a long-acting agonist of luteinizing hormone-releasing hormone (LH-RH), goserelin (Zoladex depot, ICI Pharmaceuticals, Macclesfield, UK) 3.6 mg, administered subcutaneously every 28 days. A 55% reduction (range, 38% to 84%) in uterine volume assessed by ultrasound was obtained. The greatest reduction (30%) was apparent within the first treatment cycle regardless of whether treatment was started in the early follicular or the luteal phase. Fibroid regression was inversely correlated with urinary estrogen concentration. Treatment was well tolerated and only one subject withdrew from the study before its scheduled completion. Following cessation of therapy, ovulatory menstruation returned within 3 months in the majority of the subjects, but this was accompanied by a rapid regrowth of the fibroids. This medical approach to the management of fibroids merits further investigation but as yet cannot be regarded as an alternative to surgery.
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Abstract
A long-acting LHRH agonist, Zoladex depot 3.6 mg, was administered as a monthly s.c. injection to seven premenopausal volunteers for a maximum of 6 months, starting in the luteal phase of the cycle. Transient stimulation of gonadotrophin release was observed 24 h after the initial depot, followed by sustained suppression of plasma LH, while FSH levels returned to the normal range. Plasma oestradiol concentrations fell to early follicular phase values within 14 d. Twice-weekly monitoring of urinary oestrone-3-glucuronide and pregnanediol demonstrated inhibition of ovulation and almost complete suppression of ovarian follicular activity throughout therapy. All the subjects became amenorrhoeic. Mean plasma testosterone concentrations were also significantly reduced while androstenedione remained within the pretreatment range. SHBG concentrations were not significantly reduced. After cessation of therapy, postovulatory menstruation occurred within 80 d of administration of the last depot.
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Affiliation(s)
- C P West
- Department of Obstetrics and Gynaecology, University of Edinburgh
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Abstract
A 26-year-old female with insulin-dependent diabetes of 16 years duration had a vitrectomy for a dense non-resolving vitreous haemorrhage. Two months later she became pregnant. She delivered a healthy baby and despite the known adverse effects of pregnancy on retinopathy no deterioration occurred in visual acuity or in retinal appearance.
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Critchley JA, Ellis P, Henderson CG, Ungar A, West CP. Muscarinic and nicotinic mechanisms in the responses of the adrenal medulla of the dog and cat to reflex stimuli and to cholinomimetic drugs. Br J Pharmacol 1986; 89:831-5. [PMID: 3814911 PMCID: PMC1917227 DOI: 10.1111/j.1476-5381.1986.tb11188.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
In isolated perfused adrenal glands of the cat, muscarinic and nicotinic agonists selectively released adrenaline and noradrenaline respectively. In isolated perfused adrenal glands of the dog, the output of adrenaline and noradrenaline remained in a fixed ratio at rest and when stimulated by muscarinic or by nicotinic agonists. In the anaesthetized dog, a combination of muscarinic and nicotinic antagonists was needed to block reflex responses of the adrenal medulla. A nicotinic antagonist was more effective in blocking the baroreceptor reflex response than the chemoreceptor reflex response.
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