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Franco ME, Ramirez AJ, Johanning KM, Matson CW, Lavado R. In vitro-in vivo biotransformation and phase I metabolite profiling of benzo[a]pyrene in Gulf killifish (Fundulus grandis) populations with different exposure histories. Aquat Toxicol 2022; 243:106057. [PMID: 34942459 DOI: 10.1016/j.aquatox.2021.106057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 12/10/2021] [Accepted: 12/13/2021] [Indexed: 06/14/2023]
Abstract
Chronic exposure to pollution may lead populations to display evolutionary adaptations associated with cellular and physiological mechanisms of defense against xenobiotics. This could result in differences in the way individuals of the same species, but inhabiting different areas, cope with chemical exposure. In the present study, we explore two Gulf killifish (Fundulus grandis) populations with different exposure histories for potential differences in the biotransformation of benzo[a]pyrene (BaP), and conduct a comparative evaluation of in vitro and in vivo approaches to describe the applicability of new approach methodologies (NAMs) for biotransformation assessments. Pollution-adapted and non-adapted F. grandis were subjected to intraperitoneal (IP) injections of BaP in time-course exposures, prior to measurements of CYP biotransformation activity, BaP liver concentrations, and the identification and quantification of phase I metabolites. Additionally, substrate depletion bioassays using liver S9 fractions were employed for measurements of intrinsic hepatic clearance and to evaluate the production of metabolites in vitro. Pollution-adapted F. grandis presented significantly lower CYP1A activity and intrinsic clearance rates that were 3 to 4 times lower than non-adapted fish. The metabolite profiling of BaP showed the presence of 1‑hydroxy-benzo[a]pyrene in both the in vitro and in vivo approaches but with no significant population differences. Contrarily, 9‑hydroxy-benzo[a]pyrene and benzo[a]pyrene-4,5-dihydrodiol, only identified through the in vivo approach, presented higher concentrations in the bile of pollution-adapted fish relative to non-adapted individuals. These observations further the understanding of the evolutionary adaptation of F. grandis inhabiting heavily polluted environments in the Houston Ship Channel, TX, USA, and highlight the need to consider the evolutionary history of populations of interest during the implementation of NAMs.
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Affiliation(s)
- Marco E Franco
- Department of Environmental Science, Baylor University, Waco, TX 76798, United States
| | - Alejandro J Ramirez
- Mass Spectrometry Core Facility, Baylor University, Waco, TX, 76798, United States
| | | | - Cole W Matson
- Department of Environmental Science, Baylor University, Waco, TX 76798, United States; Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX 76798, United States
| | - Ramon Lavado
- Department of Environmental Science, Baylor University, Waco, TX 76798, United States.
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Franco ME, Fernandez-Luna MT, Ramirez AJ, Lavado R. Metabolomic-based assessment reveals dysregulation of lipid profiles in human liver cells exposed to environmental obesogens. Toxicol Appl Pharmacol 2020; 398:115009. [PMID: 32353385 DOI: 10.1016/j.taap.2020.115009] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 04/10/2020] [Accepted: 04/12/2020] [Indexed: 02/08/2023]
Abstract
Significant attention has been given to the potential of environmental chemicals to disrupt lipid homeostasis at the cellular level. These chemicals, classified as obesogens, are abundantly used in a wide variety of consumer products. However, there is a significant lack of information regarding the mechanisms by which environmental exposure can contribute to the onset of obesity and non-alcoholic fatty liver disease (NAFLD). Several studies have described the interaction of potential obesogens with lipid-related peroxisome proliferator-activated receptors (PPAR). However, no studies have quantified the degree of modification to lipidomic profiles in relevant human models, making it difficult to directly link PPAR agonists to the onset of lipid-related diseases. A quantitative metabolomic approach was used to examine the dysregulation of lipid metabolism in human liver cells upon exposure to potential obesogenic compounds. The chemicals rosiglitazone, perfluorooctanoic acid, di-2-ethylexylphthalate, and tributyltin significantly increased total lipids in liver cells, being diglycerides, triglycerides and phosphatidylcholines the most prominent. Contrarily, perfluorooctane sulfonic acid and the pharmaceutical fenofibrate appeared to lower total lipid concentrations, especially those belonging to the acylcarnitine, ceramide, triglyceride, and phosphatidylcholine groups. Fluorescence microscopy analysis for cellular neutral lipids revealed significant lipid bioaccumulation upon exposure to obesogens at environmentally relevant concentrations. This integrated omics analysis provides unique mechanistic insight into the potential of these environmental pollutants to promote diseases like obesity and NAFLD. Furthermore, this study provides a significant contribution to advance the understanding of molecular signatures related to obesogenic chemicals and to the development of alternatives to in vivo experimentation.
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Affiliation(s)
- Marco E Franco
- Department of Environmental Science, Baylor University, Waco, TX 76798, United States of America
| | | | - Alejandro J Ramirez
- Mass Spectrometry Center, Baylor University, Waco, TX 76798, United States of America
| | - Ramon Lavado
- Department of Environmental Science, Baylor University, Waco, TX 76798, United States of America.
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Winn BA, Devkota L, Kuch B, MacDonough MT, Strecker TE, Wang Y, Shi Z, Gerberich JL, Mondal D, Ramirez AJ, Hamel E, Chaplin DJ, Davis P, Mason RP, Trawick ML, Pinney KG. Bioreductively Activatable Prodrug Conjugates of Combretastatin A-1 and Combretastatin A-4 as Anticancer Agents Targeted toward Tumor-Associated Hypoxia. J Nat Prod 2020; 83:937-954. [PMID: 32196334 PMCID: PMC7644341 DOI: 10.1021/acs.jnatprod.9b00773] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The natural products combretastatin A-1 (CA1) and combretastatin A-4 (CA4) function as potent inhibitors of tubulin polymerization and as selective vascular disrupting agents (VDAs) in tumors. Bioreductively activatable prodrug conjugates (BAPCs) can enhance selectivity by serving as substrates for reductase enzymes specifically in hypoxic regions of tumors. A series of CA1-BAPCs incorporating nor-methyl, mono-methyl, and gem-dimethyl nitrothiophene triggers were synthesized together with corresponding CA4-BAPCs, previously reported by Davis (Mol. Cancer Ther. 2006, 5 (11), 2886), for comparison. The CA4-gem-dimethylnitrothiophene BAPC 45 proved exemplary in comparison to its nor-methyl 43 and mono-methyl 44 congeners. It was stable in phosphate buffer (pH 7.4, 24 h), was cleaved (25%, 90 min) by NADPH-cytochrome P450 oxidoreductase (POR), was inactive (desirable prodrug attribute) as an inhibitor of tubulin polymerization (IC50 > 20 μM), and demonstrated hypoxia-selective activation in the A549 cell line [hypoxia cytotoxicity ratio (HCR) = 41.5]. The related CA1-gem-dimethylnitrothiophene BAPC 41 was also promising (HCR = 12.5) with complete cleavage (90 min) upon treatment with POR. In a preliminary in vivo dynamic bioluminescence imaging study, BAPC 45 (180 mg/kg, ip) induced a decrease (within 4 h) in light emission in a 4T1 syngeneic mouse breast tumor model, implying activation and vascular disruption.
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Affiliation(s)
- Blake A. Winn
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798-7348, United States
| | - Laxman Devkota
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798-7348, United States
| | - Bunnarack Kuch
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798-7348, United States
| | - Matthew T. MacDonough
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798-7348, United States
| | - Tracy E. Strecker
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798-7348, United States
| | - Yifan Wang
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798-7348, United States
| | - Zhe Shi
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798-7348, United States
| | - Jeni L. Gerberich
- Predictive Imaging Research Laboratory, Department of Radiology, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9058, United States
| | - Deboprosad Mondal
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798-7348, United States
| | - Alejandro J. Ramirez
- Mass Spectrometry Center, Baylor University, One Bear Place #97046, Waco, Texas 76798-7046, United States
| | - Ernest Hamel
- Screening Technologies Branch, Developmental Therapeutics Program, Division of Cancer Treatment and Diagnosis, National Cancer Institute, Frederick National Laboratory for Cancer Research, National Institutes of Health, Frederick, MD 21702, United States
| | - David J. Chaplin
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798-7348, United States
- Fast Biopharma Ltd., 10 Aston Park, Aston Rowant, OX49 5SW, United Kingdom
| | - Peter Davis
- Fast Biopharma Ltd., 10 Aston Park, Aston Rowant, OX49 5SW, United Kingdom
| | - Ralph P. Mason
- Predictive Imaging Research Laboratory, Department of Radiology, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9058, United States
| | - Mary Lynn Trawick
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798-7348, United States
| | - Kevin G. Pinney
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798-7348, United States
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Burket SR, White M, Ramirez AJ, Stanley JK, Banks KE, Waller WT, Chambliss CK, Brooks BW. Corbicula fluminea rapidly accumulate pharmaceuticals from an effluent dependent urban stream. Chemosphere 2019; 224:873-883. [PMID: 30856403 DOI: 10.1016/j.chemosphere.2019.03.014] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Revised: 02/28/2019] [Accepted: 03/03/2019] [Indexed: 05/12/2023]
Abstract
Freshwater bivalve populations are stressed by watershed development at the global scale. Though pharmaceuticals released from wastewater treatment plant effluent discharges are increasingly reported to bioaccumulate in fish, an understanding of bioaccumulation in bivalves is less defined. In the present study, we examined accumulation of 12 target pharmaceuticals in C. fluminea during a 42 day in situ study in Pecan Creek, an effluent dependent wadeable stream in north central Texas, USA. Caged clams were placed at increasing distances (5 m, 643 m, 1762 m) downstream from a municipal effluent discharge and then subsampled on study days 7, 14, 28 and 42. Acetaminophen, caffeine, carbamazepine, diltiazem, diphenhydramine, fluoxetine, norfluoxetine, sertraline, desmethylsertraline, and methylphenidate were identified in C. fluminea whole body tissue homogenates via isotope dilution liquid chromatography-tandem mass spectrometry. Tissue concentrations ranged from low μg/kg (methylphenidate) to 341 μg/kg (sertraline). By study day 7, rapid and apparent pseudo-steady state accumulation of study compounds was observed in clams; this observation continued throughout the 42 d study. Notably, elevated bioaccumulation factors (L/kg) for sertraline were observed between 3361 and 6845, which highlights the importance of developing predictive bioaccumulation models for ionizable contaminants with bivalves. Future research is also necessary to understand different routes of exposure and elimination kinetics for pharmaceutical accumulation in bivalves.
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Affiliation(s)
- S Rebekah Burket
- Department of Environmental Science, Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX, USA
| | - Mendie White
- Institute of Applied Science, University of North Texas, 704 W Mulberry St, Denton, TX, USA
| | - Alejandro J Ramirez
- Department of Environmental Science, Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX, USA; Department of Chemistry and Biochemistry, Baylor University, Waco, TX, USA
| | - Jacob K Stanley
- Department of Environmental Science, Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX, USA
| | | | - W Thomas Waller
- Institute of Applied Science, University of North Texas, 704 W Mulberry St, Denton, TX, USA
| | - C Kevin Chambliss
- Department of Environmental Science, Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX, USA; Department of Chemistry and Biochemistry, Baylor University, Waco, TX, USA
| | - Bryan W Brooks
- Department of Environmental Science, Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX, USA; School of Environment, Jinan University, Guangzhou, China.
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Church DD, Schwarz NA, Spillane MB, McKinley-Barnard SK, Andre TL, Ramirez AJ, Willoughby DS. l-Leucine Increases Skeletal Muscle IGF-1 but Does Not Differentially Increase Akt/mTORC1 Signaling and Serum IGF-1 Compared to Ursolic Acid in Response to Resistance Exercise in Resistance-Trained Men. J Am Coll Nutr 2016; 35:627-638. [PMID: 27331824 DOI: 10.1080/07315724.2015.1132019] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
OBJECTIVE Ursolic acid administration following resistance exercise increases mammalian target of rapamycin complex 1 (mTORC1) activity and skeletal muscle IGF-1 concentration in murines in a manner similar to l-leucine yet remains unexamined in humans. This study examined serum and skeletal muscle insulin-like growth factor-1 (IGF-1) and Akt/mTORC1 signaling activity following ingestion of either ursolic acid or l-leucine immediately after resistance exercise. METHODS Nine resistance-trained men performed 3 lower-body resistance exercise sessions involving 4 sets of 8-10 repetitions at 75%-80% one repetition maximum (1-RM) on the angled leg press and knee extension exercises. Immediately following each session, participants orally ingested 3 g cellulose placebo (PLC), l-leucine (LEU), or ursolic acid (UA). Blood samples were obtained pre-exercise and at 0.5, 2, and 6 hours postexercise. Muscle biopsies were obtained pre-exercise and at 2 and 6 hours postexercise. RESULTS Plasma leucine increased in LEU at 2 hours postexercise compared to PLC (p = 0.04). Plasma ursolic acid increased in UA at 2 h and 6 hours postexercise compared to PLC and LEU (p < 0.003). No significant differences were observed for serum insulin (p = 0.98) and IGF-1 (p = 0.99) or skeletal muscle IGF-1 receptor (IGF-1R; p = 0.84), Akt (p = 0.55), mTOR (p = 0.09), and p70S6K (p = 0.98). Skeletal muscle IGF-1 was significantly increased in LEU at 2 hours postexercise (p = 0.03) and 6 hours postexercise (p = 0.04) compared to PLC and UA. CONCLUSION Three grams of l-leucine and ursolic acid had no effect on Akt/mTORC1 signaling or serum insulin or IGF-1; however, l-leucine increased skeletal muscle IGF-1 concentration in resistance-trained men.
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Affiliation(s)
- David D Church
- a Exercise and Biochemical Nutrition Lab, Department of Health , Human Performance, and Recreation, College of Arts and Sciences, Baylor University , Waco , Texas
| | - Neil A Schwarz
- a Exercise and Biochemical Nutrition Lab, Department of Health , Human Performance, and Recreation, College of Arts and Sciences, Baylor University , Waco , Texas
| | - Mike B Spillane
- a Exercise and Biochemical Nutrition Lab, Department of Health , Human Performance, and Recreation, College of Arts and Sciences, Baylor University , Waco , Texas
| | - Sarah K McKinley-Barnard
- a Exercise and Biochemical Nutrition Lab, Department of Health , Human Performance, and Recreation, College of Arts and Sciences, Baylor University , Waco , Texas
| | - Tom L Andre
- a Exercise and Biochemical Nutrition Lab, Department of Health , Human Performance, and Recreation, College of Arts and Sciences, Baylor University , Waco , Texas
| | - Alejandro J Ramirez
- b Mass Spectrometry Center , College of Arts and Sciences, Baylor University , Waco , Texas
| | - Darryn S Willoughby
- a Exercise and Biochemical Nutrition Lab, Department of Health , Human Performance, and Recreation, College of Arts and Sciences, Baylor University , Waco , Texas
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Campbell J, Pyer M, Rogers S, Jones J, Ramirez AJ, Forbes LJL. Promoting early presentation of breast cancer in women over 70 years old in general practice. J Public Health (Oxf) 2015; 38:591-598. [PMID: 26359315 DOI: 10.1093/pubmed/fdv125] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Delay in presentation contributes to poorer survival of older women with breast cancer. Research has shown the effectiveness of the promoting early presentation (PEP) intervention when delivered by radiographers in the NHS Breast Screening Programme. This paper investigates the effectiveness of the intervention when delivered by practice nurses in general practice. METHODS The Breast Cancer Awareness Measure was used to compare participants' awareness of breast cancer before, 1 month after and 12 months after the delivery of the PEP intervention. Five hundred and fifty-six women aged over 70 years took part, 308 of whom returned all three surveys. RESULTS The intervention was associated with increased awareness of non-lump breast symptoms and reported breast check frequency. There was a marked increase in breast cancer awareness which persisted for 12 months. Less than 5% of women were classified as 'breast cancer aware' before the intervention, rising to over 25% 1 month afterwards. This percentage dropped slightly after 1 year to just below 20%. CONCLUSION Delivery of the PEP intervention in general practice was very effective at raising the awareness of breast cancer among older women. Primary care settings are well placed to enhance the reach of this kind of intervention to at-risk women.
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Affiliation(s)
- J Campbell
- Institute of Health and Wellbeing, University of Northampton, Northampton NN2 7AL, UK
| | - M Pyer
- Institute of Health and Wellbeing, University of Northampton, Northampton NN2 7AL, UK
| | - S Rogers
- Clinical Lead for Applied Health Research, Northamptonshire Healthcare Foundation Trust, Northampton NN5 6UD, UK University of Leicester, Leicester LE1 6TP, UK
| | - J Jones
- Institute of Health and Wellbeing, University of Northampton, Northampton NN2 7AL, UK
| | - A J Ramirez
- Promoting Early Presentation Group, King's College London, London SE1 3QD, UK
| | - L J L Forbes
- Promoting Early Presentation Group, King's College London, London SE1 3QD, UK
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Niksic M, Rachet B, Warburton FG, Wardle J, Ramirez AJ, Forbes LJL. Cancer symptom awareness and barriers to symptomatic presentation in England--are we clear on cancer? Br J Cancer 2015; 113:533-42. [PMID: 26125450 PMCID: PMC4522620 DOI: 10.1038/bjc.2015.164] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 04/05/2015] [Accepted: 04/22/2015] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Low cancer awareness may contribute to delayed diagnosis and poor cancer survival. We aimed to quantify socio-demographic differences in cancer symptom awareness and barriers to symptomatic presentation in the English population. METHODS Using a uniquely large data set (n=49 270), we examined the association of cancer symptom awareness and barriers to presentation with age, gender, marital status and socio-economic position (SEP), using logistic regression models to control for confounders. RESULTS The youngest and oldest, the single and participants with the lowest SEP recognised the fewest cancer symptoms, and reported most barriers to presentation. Recognition of nine common cancer symptoms was significantly lower, and embarrassment, fear and difficulties in arranging transport to the doctor's surgery were significantly more common in participants living in the most deprived areas than in the most affluent areas. Women were significantly more likely than men to both recognise common cancer symptoms and to report barriers. Women were much more likely compared with men to report that fear would put them off from going to the doctor. CONCLUSIONS Large and robust socio-demographic differences in recognition of some cancer symptoms, and perception of some barriers to presentation, highlight the need for targeted campaigns to encourage early presentation and improve cancer outcomes.
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Affiliation(s)
- M Niksic
- Promoting Early Cancer Presentation Group, King's College London, Guy's Hospital Campus, 42 Weston Street, London SE1 3QD, UK
| | - B Rachet
- Cancer Research UK Cancer Survival Group, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - F G Warburton
- Promoting Early Cancer Presentation Group, King's College London, Guy's Hospital Campus, 42 Weston Street, London SE1 3QD, UK
| | - J Wardle
- Health Behaviour Research Centre, Department of Epidemiology and Public Health, University College London, Gower Street, London WC1E 6BT, UK
| | - A J Ramirez
- Promoting Early Cancer Presentation Group, King's College London, Guy's Hospital Campus, 42 Weston Street, London SE1 3QD, UK
| | - L J L Forbes
- Promoting Early Cancer Presentation Group, King's College London, Guy's Hospital Campus, 42 Weston Street, London SE1 3QD, UK
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Kellermann G, Montoro LA, Giovanetti LJ, dos Santos Claro PC, Zhang L, Ramirez AJ, Requejo FG, Craievich AF. Controlled growth of extended arrays of CoSi2 hexagonal nanoplatelets buried in Si(001), Si(011) and Si(111) wafers. Phys Chem Chem Phys 2015; 17:4945-51. [PMID: 25594082 DOI: 10.1039/c4cp04738a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Because of their high electrical conductivity CoSi2 nanostructures are potential candidates for preparing ordered nano-arrays to be used as electrode interconnectors and contacts in microelectronic devices. We here describe a controlled procedure for the endotaxial growth of hexagonal CoSi2 nanoplatelets buried in differently oriented single crystalline Si wafers on which a Co-doped SiO2 thin film was previously deposited. These nanomaterials were obtained by a clean procedure consisting of isothermal annealing at 750 °C under a He atmosphere of Co-doped SiO2 thin films deposited onto the surface of three differently oriented flat Si substrates, namely Si(001), Si(011) and Si(111). Buried CoSi2 nanoplatelets are in all cases spontaneously formed as a consequence of the diffusion of Co atoms into the silicon wafer and their reaction with host Si atoms. Our TEM and GISAXS analyses demonstrated that these arrays, irrespective of host Si orientation, consist of CoSi2 hexagonal nanoplatelets in all cases parallel to Si{111} crystallographic planes. Additionally, the dimensions of the nanoplatelets were consistently determined by TEM and GISAXS for the three different host Si single crystal orientations.
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Affiliation(s)
- G Kellermann
- Departamento de Física, Universidade Federal do Paraná, Caixa Postal 19091, Curitiba, Paraná 81531-990, Brazil
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Forbes LJL, Simon AE, Warburton F, Boniface D, Brain KE, Dessaix A, Donnelly C, Haynes K, Hvidberg L, Lagerlund M, Lockwood G, Tishelman C, Vedsted P, Vigmostad MN, Ramirez AJ, Wardle J. Erratum: Differences in cancer awareness and beliefs between Australia, Canada, Denmark, Norway, Sweden and the UK (the International Cancer Benchmarking Partnership): do they contribute to differences in cancer survival? Br J Cancer 2014. [PMCID: PMC4264454 DOI: 10.1038/bjc.2014.562] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Baron DM, Ramirez AJ, Bulitko V, Madan CR, Greiner A, Hurd PL, Spetch ML. Practice makes proficient: pigeons (Columba livia) learn efficient routes on full-circuit navigational traveling salesperson problems. Anim Cogn 2014; 18:53-64. [DOI: 10.1007/s10071-014-0776-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Revised: 06/06/2014] [Accepted: 06/11/2014] [Indexed: 11/25/2022]
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Torres EA, Montoro F, Righetto RD, Ramirez AJ. Development of high-temperature strain instrumentation for in situ SEM evaluation of ductility dip cracking. J Microsc 2014; 254:157-65. [PMID: 24749869 DOI: 10.1111/jmi.12128] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 03/18/2014] [Indexed: 10/25/2022]
Abstract
Nowadays, the implementation of sophisticated in situ electron microscopy tests is providing new insights in several areas. In this work, an in situ high-temperature strain test into a scanning electron microscope was developed. This setup was used to study the grain boundary sliding mechanism and its effect on the ductility dip cracking. This methodology was applied to study the mechanical behaviour of Ni-base filler metal alloys ERNiCrFe-7 and ERNiCr-3, which were evaluated between 700°C and 1000°C. The ductility dip cracking susceptibility (threshold strain; εmin) for both alloys was quantified. The εmin of ERNiCrFe-7 and ERNiCr-3 alloys were 7.5% and 16.5%, respectively, confirming a better resistance of ERNiCr-3 to ductility dip cracking. Furthermore, two separate components of grain boundary sliding, pure sliding (Sp) and deformation sliding (Sd), were identified and quantified. A direct and quantitative link between grain boundary tortuosity, grain boundary sliding and ductility dip cracking resistance has been established for the ERNiCrFe-7 and ERNiCr-3 alloys.
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Affiliation(s)
- E A Torres
- Brazilian Nanotechnology National Laboratory (LNNano), Campinas, SP, Brazil; Now at Faculty of Engineering, Instituto Tecnologico Metropolitano (ITM), Medellin, Antioquia, Colombia
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Du B, Price AE, Scott WC, Kristofco LA, Ramirez AJ, Chambliss CK, Yelderman JC, Brooks BW. Comparison of contaminants of emerging concern removal, discharge, and water quality hazards among centralized and on-site wastewater treatment system effluents receiving common wastewater influent. Sci Total Environ 2014; 466-467:976-84. [PMID: 23988745 DOI: 10.1016/j.scitotenv.2013.07.126] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Revised: 07/31/2013] [Accepted: 07/31/2013] [Indexed: 05/22/2023]
Abstract
A comparative understanding of effluent quality of decentralized on-site wastewater treatment systems, particularly for contaminants of emerging concern (CECs), remains less understood than effluent quality from centralized municipal wastewater treatment plants. Using a novel experimental facility with common influent wastewater, effluent water quality from a decentralized advanced aerobic treatment system (ATS) and a typical septic treatment system (STS) coupled to a subsurface flow constructed wetland (WET) were compared to effluent from a centralized municipal treatment plant (MTP). The STS did not include soil treatment, which may represent a system not functioning properly. Occurrence and discharge of a range of CECs were examined using isotope dilution liquid chromatography-tandem mass spectrometry during fall and winter seasons. Conventional parameters, including total suspended solids, carbonaceous biochemical oxygen demand and nutrients were also evaluated from each treatment system. Water quality of these effluents was further examined using a therapeutic hazard modeling approach. Of 19 CECs targeted for study, the benzodiazepine pharmaceutical diazepam was the only CEC not detected in all wastewater influent and effluent samples over two sampling seasons. Diphenhydramine, codeine, diltiazem, atenolol, and diclofenac exhibited significant (p<0.05) seasonal differences in wastewater influent concentrations. Removal of CECs by these wastewater treatment systems was generally not influenced by season. However, significant differences (p<0.05) for a range of water quality indicators were observed among the various treatment technologies. For example, removal of most CECs by ATS was generally comparable to MTP. Lowest removal of most CECs was observed for STS; however, removal was improved when coupling the STS to a WET. Across the treatment systems examined, the majority of pharmaceuticals observed in on-site and municipal effluent discharges were predicted to potentially present therapeutic hazards to fish.
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Affiliation(s)
- Bowen Du
- The Institute of Ecological, Earth and Environmental Sciences, Baylor University, Waco, TX 76798, USA; Department of Environmental Science, Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX 76798, USA.
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Forbes LJL, Warburton F, Richards MA, Ramirez AJ. OP51 What are the Commonest Symptoms of Cancer and the Risk Factors for Delay in Presentation with Cancer Symptoms? Br J Soc Med 2013. [DOI: 10.1136/jech-2013-203126.51] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Strachan JP, Yang JJ, Montoro LA, Ospina CA, Ramirez AJ, Kilcoyne ALD, Medeiros-Ribeiro G, Williams RS. Characterization of electroforming-free titanium dioxide memristors. Beilstein J Nanotechnol 2013; 4:467-73. [PMID: 23946916 PMCID: PMC3740802 DOI: 10.3762/bjnano.4.55] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Accepted: 07/20/2013] [Indexed: 05/10/2023]
Abstract
Metal-insulator-metal (MIM) structures based on titanium dioxide have demonstrated reversible and non-volatile resistance-switching behavior and have been identified with the concept of the memristor. Microphysical studies suggest that the development of sub-oxide phases in the material drives the resistance changes. The creation of these phases, however, has a number of negative effects such as requiring an elevated voltage, increasing the device-to-device variability, damaging the electrodes due to oxygen evolution, and ultimately limiting the device lifetime. In this work we show that the deliberate inclusion of a sub-oxide layer in the MIM structure maintains the favorable switching properties of the device, while eliminating many of the negative effects. Electrical and microphysical characterization of the resulting structures was performed, utilizing X-ray and electron spectroscopy and microscopy. In contrast to structures which are not engineered with a sub-oxide layer, we observed dramatically reduced microphysical changes after electrical operation.
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Affiliation(s)
- John Paul Strachan
- nanoElectronics Research Group, HP Labs, 1501 Page Mill Rd, Palo Alto, CA 94304, USA
| | - J Joshua Yang
- nanoElectronics Research Group, HP Labs, 1501 Page Mill Rd, Palo Alto, CA 94304, USA
| | - L A Montoro
- Brazilian Nanotechnology National Laboratory, CP 6192, Campinas, SP 13083-970, Brazil
- Universidade Federal de Minas Gerais, 31270-901, Belo Horizonte, MG, Brazil
| | - C A Ospina
- Brazilian Nanotechnology National Laboratory, CP 6192, Campinas, SP 13083-970, Brazil
| | - A J Ramirez
- Brazilian Nanotechnology National Laboratory, CP 6192, Campinas, SP 13083-970, Brazil
| | - A L D Kilcoyne
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Gilberto Medeiros-Ribeiro
- nanoElectronics Research Group, HP Labs, 1501 Page Mill Rd, Palo Alto, CA 94304, USA
- Universidade Federal de Minas Gerais, 31270-901, Belo Horizonte, MG, Brazil
| | - R Stanley Williams
- nanoElectronics Research Group, HP Labs, 1501 Page Mill Rd, Palo Alto, CA 94304, USA
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Forbes LJL, Simon AE, Warburton F, Boniface D, Brain KE, Dessaix A, Donnelly C, Haynes K, Hvidberg L, Lagerlund M, Lockwood G, Tishelman C, Vedsted P, Vigmostad MN, Ramirez AJ, Wardle J. Differences in cancer awareness and beliefs between Australia, Canada, Denmark, Norway, Sweden and the UK (the International Cancer Benchmarking Partnership): do they contribute to differences in cancer survival? Br J Cancer 2013; 108:292-300. [PMID: 23370208 PMCID: PMC3566814 DOI: 10.1038/bjc.2012.542] [Citation(s) in RCA: 164] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Revised: 10/30/2012] [Accepted: 11/01/2012] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND There are wide international differences in 1-year cancer survival. The UK and Denmark perform poorly compared with other high-income countries with similar health care systems: Australia, Canada and Sweden have good cancer survival rates, Norway intermediate survival rates. The objective of this study was to examine the pattern of differences in cancer awareness and beliefs across these countries to identify where these might contribute to the pattern of survival. METHODS We carried out a population-based telephone interview survey of 19079 men and women aged ≥ 50 years in Australia, Canada, Denmark, Norway, Sweden and the UK using the Awareness and Beliefs about Cancer measure. RESULTS Awareness that the risk of cancer increased with age was lower in the UK (14%), Canada (13%) and Australia (16%) but was higher in Denmark (25%), Norway (29%) and Sweden (38%). Symptom awareness was no lower in the UK and Denmark than other countries. Perceived barriers to symptomatic presentation were highest in the UK, in particular being worried about wasting the doctor's time (UK 34%; Canada 21%; Australia 14%; Denmark 12%; Norway 11%; Sweden 9%). CONCLUSION The UK had low awareness of age-related risk and the highest perceived barriers to symptomatic presentation, but symptom awareness in the UK did not differ from other countries. Denmark had higher awareness of age-related risk and few perceived barriers to symptomatic presentation. This suggests that other factors must be involved in explaining Denmark's poor survival rates. In the UK, interventions that address barriers to prompt presentation in primary care should be developed and evaluated.
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Affiliation(s)
- L J L Forbes
- King's College London Promoting Early Presentation Group, Capital House, 42 Weston Street, London SE1 3QD, UK.
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Shi Y, Mowery RA, Ashley J, Hentz M, Ramirez AJ, Bilgicer B, Slunt-Brown H, Borchelt DR, Shaw BF. Abnormal SDS-PAGE migration of cytosolic proteins can identify domains and mechanisms that control surfactant binding. Protein Sci 2012; 21:1197-209. [PMID: 22692797 DOI: 10.1002/pro.2107] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The amino acid substitution or post-translational modification of a cytosolic protein can cause unpredictable changes to its electrophoretic mobility during SDS-PAGE. This type of "gel shifting" has perplexed biochemists and biologists for decades. We identify a mechanism for "gel shifting" that predominates among a set of ALS (amyotrophic lateral sclerosis) mutant hSOD1 (superoxide dismutase) proteins, post-translationally modified hSOD1 proteins, and homologous SOD1 proteins from different organisms. By first comparing how 39 amino acid substitutions throughout hSOD1 affected SDS-PAGE migration, we found that substitutions that caused gel shifting occurred within a single polyacidic domain (residues ~80-101), and were nonisoelectric. Substitutions that decreased the net negative charge of domain 80-101 increased migration; only one substitution increased net negative charge and slowed migration. Capillary electrophoresis, circular dichroism, and size exclusion chromatography demonstrated that amino acid substitutions increase migration during SDS-PAGE by promoting the binding of three to four additional SDS molecules, without significantly altering the secondary structure or Stokes radius of hSOD1-SDS complexes. The high negative charge of domain 80-101 is required for SOD1 gel shifting: neutralizing the polyacidic domain (via chimeric mouse-human SOD1 fusion proteins) inhibited amino acid substitutions from causing gel shifting. These results demonstrate that the pattern of gel shifting for mutant cytosolic proteins can be used to: (i) identify domains in the primary structure that control interactions between denatured cytosolic proteins and SDS and (ii) identify a predominant chemical mechanism for the interaction (e.g., hydrophobic vs. electrostatic).
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Affiliation(s)
- Yunhua Shi
- Department of Chemistry and Biochemistry, Baylor University, Waco, Texas 76706, USA
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Forbes LJL, Linsell L, Atkins L, Burgess C, Tucker L, Omar L, Ramirez AJ. A promoting early presentation intervention increases breast cancer awareness in older women after 2 years: a randomised controlled trial. Br J Cancer 2011; 105:18-21. [PMID: 21654683 PMCID: PMC3137419 DOI: 10.1038/bjc.2011.205] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Background: We have developed the Promoting Early Presentation (PEP) Intervention to equip older women with the knowledge, skills, confidence and motivation to present promptly with breast symptoms, and thereby improve survival from breast cancer. The PEP Intervention consists of a 10-min interaction between a radiographer and an older woman, supported by a booklet. Our previous report showed that at 1 year, the PEP intervention increased the proportion who were breast cancer aware compared with usual care. Methods: We randomised 867 women aged 67–70 years attending for their final routine appointment on the National Health Service Breast Screening Programme to receive the PEP Intervention, a booklet alone or usual care. The primary outcome was breast cancer awareness measured using a validated questionnaire asking about knowledge of breast cancer symptoms, knowledge that the risk of breast cancer increases with age and breast checking behaviour. Results: At 2 years, the PEP Intervention increased the proportion who were breast cancer aware compared with usual care (21 vs 6% odds ratio 8.1, 95% confidence interval 2.7–25.0). Conclusions: The uniquely large and sustained effect of the PEP Intervention on breast cancer awareness increases the likelihood that a woman will present promptly should she develop breast cancer symptoms up to many years later.
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Affiliation(s)
- L J L Forbes
- Promoting Early Presentation Group, Kings College London, Adamson Centre for Mental Health, South Wing, St Thomas' Hospital, London SE1 7EH, UK.
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Macleod U, Mitchell ED, Burgess C, Macdonald S, Ramirez AJ. Risk factors for delayed presentation and referral of symptomatic cancer: evidence for common cancers. Br J Cancer 2010; 101 Suppl 2:S92-S101. [PMID: 19956172 PMCID: PMC2790698 DOI: 10.1038/sj.bjc.6605398] [Citation(s) in RCA: 355] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Background: It has been suggested that the known poorer survival from cancer in the United Kingdom, compared with other European countries, can be attributed to more advanced cancer stage at presentation. There is, therefore, a need to understand the diagnostic process, and to ascertain the risk factors for increased time to presentation. Methods: We report the results from two worldwide systematic reviews of the literature on patient-mediated and practitioner-mediated delays, identifying the factors that may influence these. Results: Across cancer sites, non-recognition of symptom seriousness is the main patient-mediated factor resulting in increased time to presentation. There is strong evidence of an association between older age and patient delay for breast cancer, between lower socio-economic status and delay for upper gastrointestinal and urological cancers and between lower education level and delay for breast and colorectal cancers. Fear of cancer is a contributor to delayed presentation, while sanctioning of help seeking by others can be a powerful mediator of reduced time to presentation. For practitioner delay, ‘misdiagnosis’ occurring either through treating patients symptomatically or relating symptoms to a health problem other than cancer, was an important theme across cancer sites. For some cancers, this could also be linked to inadequate patient examination, use of inappropriate tests or failing to follow-up negative or inconclusive test results. Conclusion: Having sought help for potential cancer symptoms, it is therefore important that practitioners recognise these symptoms, and examine, investigate and refer appropriately.
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Affiliation(s)
- U Macleod
- General Practice and Primary Care, Division of Community Based Sciences, Faculty of Medicine, University of Glasgow, 1 Horselethill Road, Glasgow, UK.
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Linsell L, Forbes LJL, Kapari M, Burgess C, Omar L, Tucker L, Ramirez AJ. A randomised controlled trial of an intervention to promote early presentation of breast cancer in older women: effect on breast cancer awareness. Br J Cancer 2009; 101 Suppl 2:S40-8. [PMID: 19956161 PMCID: PMC2790707 DOI: 10.1038/sj.bjc.6605389] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND There is virtually no evidence for the effectiveness of interventions to promote early presentation in breast cancer. We aimed to test the efficacy of an intervention to equip older women with the knowledge, skills, confidence and motivation to detect symptoms and seek help promptly, with the aim of promoting early presentation with breast cancer symptoms. METHODS We randomised 867 women aged 67-70 years attending for their final routine appointment on the UK NHS Breast Screening Programme to receive: a scripted 10-min interaction with a radiographer plus a booklet, a booklet alone or usual care. The primary outcome was whether or not a woman was breast cancer aware based on knowledge of breast cancer symptoms and age-related risk, and reported breast checking. RESULTS At 1 month, the intervention increased the proportion who were breast cancer aware compared with usual care (interaction arm: 32.8% vs 4.1%; odds ratio (OR): 24.0, 95% confidence interval (CI): 7.7-73.7; booklet arm: 12.7% vs 4.1%; OR: 4.4, 95% CI: 1.6-12.0). At 1 year, the effects of the interaction plus booklet, and the booklet, on breast cancer awareness were largely sustained, although the interaction plus booklet remained much more effective. CONCLUSIONS An intervention to equip older women with the knowledge, skills, confidence and motivation to detect breast cancer symptoms and seek help promptly increases breast cancer awareness at 1 year. Future research will evaluate whether the intervention promotes early presentation and reduces breast cancer mortality.
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Affiliation(s)
- L Linsell
- King's College London, Cancer Research UK Promoting Early Presentation Group, Institute of Psychiatry, St Thomas' Hospital, London SE1 7EH, UK
| | - L J L Forbes
- King's College London, Cancer Research UK Promoting Early Presentation Group, Institute of Psychiatry, St Thomas' Hospital, London SE1 7EH, UK
| | - M Kapari
- King's College London, Cancer Research UK Promoting Early Presentation Group, Institute of Psychiatry, St Thomas' Hospital, London SE1 7EH, UK
| | - C Burgess
- King's College London, Cancer Research UK Promoting Early Presentation Group, Institute of Psychiatry, St Thomas' Hospital, London SE1 7EH, UK
| | - L Omar
- King's College London, Cancer Research UK Promoting Early Presentation Group, Institute of Psychiatry, St Thomas' Hospital, London SE1 7EH, UK
| | - L Tucker
- King's College London, Cancer Research UK Promoting Early Presentation Group, Institute of Psychiatry, St Thomas' Hospital, London SE1 7EH, UK
| | - A J Ramirez
- King's College London, Cancer Research UK Promoting Early Presentation Group, Institute of Psychiatry, St Thomas' Hospital, London SE1 7EH, UK
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Ramirez AJ, Brain RA, Usenko S, Mottaleb MA, O'Donnell JG, Stahl LL, Wathen JB, Snyder BD, Pitt JL, Perez-Hurtado P, Dobbins LL, Brooks BW, Chambliss CK. Occurrence of pharmaceuticals and personal care products in fish: results of a national pilot study in the United States. Environ Toxicol Chem 2009; 28:2587-97. [PMID: 19320536 DOI: 10.1897/08-561.1] [Citation(s) in RCA: 152] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2008] [Accepted: 02/18/2009] [Indexed: 05/24/2023]
Abstract
Pharmaceuticals and personal care products are being increasingly reported in a variety of biological matrices, including fish tissue; however, screening studies have presently not encompassed broad geographical areas. A national pilot study was initiated in the United States to assess the accumulation of pharmaceuticals and personal care products in fish sampled from five effluent-dominated rivers that receive direct discharge from wastewater treatment facilities in Chicago, Illinois; Dallas, Texas; Orlando, Florida; Phoenix, Arizona; and West Chester, Pennsylvania, USA. Fish were also collected from the Gila River, New Mexico, USA, as a reference condition expected to be minimally impacted by anthropogenic influence. High performance liquid chromatography-tandem mass spectrometry analysis of pharmaceuticals revealed the presence of norfluoxetine, sertraline, diphenhydramine, diltiazem, and carbamazepine at nanogram-per-gram concentrations in fillet composites from effluent-dominated sampling locations; the additional presence of fluoxetine and gemfibrozil was confirmed in liver tissue. Sertraline was detected at concentrations as high as 19 and 545 ng/g in fillet and liver tissue, respectively. Gas chromatography-tandem mass spectrometry analysis of personal care products in fillet composites revealed the presence of galaxolide and tonalide at maximum concentrations of 2,100 and 290 ng/g, respectively, and trace levels of triclosan. In general, more pharmaceuticals were detected at higher concentrations and with greater frequency in liver than in fillet tissues. Higher lipid content in liver tissue could not account for this discrepancy as no significant positive correlations were found between accumulated pharmaceutical concentrations and lipid content for either tissue type from any sampling site. In contrast, accumulation of the personal care products galaxolide and tonalide was significantly related to lipid content. Results suggest that the detection of pharmaceuticals and personal care products was dependent on the degree of wastewater treatment employed.
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Affiliation(s)
- Alejandro J Ramirez
- Department of Chemistry and Biochemistry, Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX 76798, USA
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Mottaleb MA, Usenko S, O’Donnell JG, Ramirez AJ, Brooks BW, Chambliss CK. Gas chromatography–mass spectrometry screening methods for select UV filters, synthetic musks, alkylphenols, an antimicrobial agent, and an insect repellent in fish. J Chromatogr A 2009; 1216:815-23. [DOI: 10.1016/j.chroma.2008.11.072] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2007] [Revised: 11/12/2008] [Accepted: 11/17/2008] [Indexed: 11/28/2022]
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Brain RA, Ramirez AJ, Fulton BA, Chambliss CK, Brooks BW. Herbicidal effects of sulfamethoxazole in Lemna gibba: using p-aminobenzoic acid as a biomarker of effect. Environ Sci Technol 2008; 42:8965-8970. [PMID: 19192826 DOI: 10.1021/es801611a] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Sulfamethoxazole (SMX) is among the most frequently detected antibiotics in the environment, heavily used in both human therapy and agriculture. Like other sulfonamides, SMX disrupts the folate biosynthetic pathway in bacteria, which was recently established as identical to that of plants, raising concerns over nontarget toxicity. Consequently, Lemna gibba was exposed to SMX to evaluate phytotoxic potency and mode of action (MOA) by HPLC-MS/MS measurement of p-aminobenzoic acid (pABA) metabolite levels, a precursor to folate biosynthesis and substrate of the target enzyme dihydropteroate synthase (DHPS). pABA levels were found to increase upon exposure to SMX following an exponential rise to a maxima regression model in a concentration-dependent manner. The EC50 for pABA content was 3.36 microg/L, 20 times lower than that of fresh weight (61.6 microg/L) and 40 times lower than frond number (132 microg/L) responses. These results suggest that, as in bacteria, sulfonamide antibiotics specifically disrupt folate biosynthesis via inhibition of DHPS. Analysis of pABA concentrations appears to provide a sulfonamide-specific biomarker of effect based on MOA with exceptional diagnostic capacity and sensitivity compared to traditional morphological end points. Using the EC50 for pABA content, a potential hazard was identified for L. gibba exposed to SMX, which would not have been detected based upon traditional standardized morphological approaches.
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Affiliation(s)
- Richard A Brain
- Center for Reservoir and Aquatic Systems Research, Department of Environmental Science, Baylor University, Waco, Texas 76798, USA.
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Burgess CC, Bish AM, Hunter HS, Salkovskis P, Michell M, Whelehan P, Ramirez AJ. Promoting early presentation of breast cancer: development of a psycho-educational intervention. Chronic Illn 2008; 4:13-27. [PMID: 18322026 DOI: 10.1177/1742395307084404] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVES Women who delay presenting with breast cancer have a reduced chance of survival. Older women, who are at greater risk of developing breast cancer, are more likely to delay presenting with the disease. The aim of this developmental work was to design a psycho-educational intervention to promote early help-seeking by older women with breast cancer symptoms. We also aimed to demonstrate the feasibility of implementing the intervention with women attending for their final invited mammogram in the National Health Service (NHS) Breast Screening Programme. METHODS The intervention was designed to address the factors associated with delayed presentation by women with breast cancer. These risk factors were placed in a theoretical framework to understand patient delay. The intervention incorporated behavioural change techniques that, according to previous research, have been demonstrated to be effective. RESULTS The intervention was developed in two formats to be delivered by diagnostic radiographers: a booklet alone and a brief interview plus the booklet. The intervention was acceptable to both older women and healthcare professionals in the NHS Breast Screening Programme. DISCUSSION The intervention will be tested ultimately in a multicentre randomized controlled trial to determine whether it can reduce the proportion of older women who delay their presentation and thereby save lives.
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Affiliation(s)
- C C Burgess
- Cancer Research UK London Psychosocial Group, Institute of Psychiatry, Kings College London Adamson Centre, St Thomas' Hospital, London SE1 7EH, UK.
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Stanley JK, Ramirez AJ, Chambliss CK, Brooks BW. Enantiospecific sublethal effects of the antidepressant fluoxetine to a model aquatic vertebrate and invertebrate. Chemosphere 2007; 69:9-16. [PMID: 17582462 DOI: 10.1016/j.chemosphere.2007.04.080] [Citation(s) in RCA: 175] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2006] [Revised: 04/19/2007] [Accepted: 04/29/2007] [Indexed: 05/03/2023]
Abstract
Many contaminants are chiral compounds with enantiomers that may differ markedly in environmental fate, bioavailability, and toxicity. Enantiospecific environmental fate and ecotoxicological information are lacking for many chiral contaminants. The primary objective of this investigation included an assessment of potential enantiospecific differences in sublethal standardized and behavioral responses of the model organisms Pimephales promelas (teleost) and Daphnia magna (crustacean) to the widely prescribed chiral antidepressant fluoxetine. Endpoints assessed included D. magna immobilization, reproduction, and grazing rate and P. promelas survival, growth, and feeding rate. S-Fluoxetine was found to be more toxic to sublethal standardized and behavioral endpoints in P. promelas, potentially because its primary active metabolite, S-norfluoxetine, is more potent than the same metabolite of R-fluoxetine in mammals. This was not observed for D. magna responses. This differential enantiospecific response between model organisms may have resulted from closer target homology between mammals and fish than between mammals and crustaceans. P. promelas feeding rate, an ecologically relevant and mode-of-action related response, was the most sensitive endpoint tested for R- and S-fluoxetine with 10% effect concentration (EC10) values (+/-SE) of 16.1 (+/-20.2) and 3.7 (+/-4.6) microg l(-1), respectively. Up to a 9.4-fold difference in toxicity between enantiomers was observed; P. promelas growth EC10s (+/-SE) for R- and S-fluoxetine were 132.9 (+/-21.2) and 14.1 (+/-8.1) microg l(-1), respectively. Such differences in sublethal responses to fluoxetine enantiomers suggest that enantiospecific toxicity and mode-of-action related responses that are ecologically relevant (e.g., feeding rate) should be considered in future ecological hazard and risk assessments for chiral contaminants.
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Affiliation(s)
- Jacob K Stanley
- Center for Reservoir and Aquatic Systems Research, Baylor University, One Bear Place # 97266, Waco, TX 76798-7266, United States.
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Abstract
A liquid chromatography-tandem mass spectrometry (LC-MS/MS) screening method has been developed targeting 23 pharmaceuticals and 2 metabolites with differing physicochemical properties in fish tissue. Reversed-phase separation of target compounds was achieved using a C18 column and a nonlinear gradient consisting of 0.1% (v/v) formic acid and methanol. Eluted analytes were introduced into the mass analyzer using positive or negative electrospray ionization, as appropriate. A variety of extraction solvents, differing in polarity, pH, or both, were investigated in order to assess recovery of target compounds from 1-g tissue homogenates. Among 10 solvents tested, a 1:1 mixture of 0.1 M aqueous acetic acid (pH 4) and methanol was identified as optimal, resulting in extraction recoveries for 24 of 25 compounds exceeding 60%. Tissue extracts were found to influence the LC-MS/MS response for several analytes. Consequently, matrix-matched calibration standards were employed to determine analyte concentrations in environmental samples. Statistically derived method detection limits were <6 ng/g for most analytes. The method was subsequently used to screen for target analytes in fish from an effluent-dominated stream. Diphenhydramine, diltiazem, carbamazepine, and norfluoxetine were detected in 11 of 11 environmental samples at concentrations ranging from 0.11 to 5.14 ng/g.
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Affiliation(s)
- Alejandro J Ramirez
- Department of Chemistry & Biochemistry, Baylor University, Waco, Texas 76798, USA
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Burgess CC, Potts HWW, Hamed H, Bish AM, Hunter MS, Richards MA, Ramirez AJ. Why do older women delay presentation with breast cancer symptoms? Psychooncology 2007; 15:962-8. [PMID: 16511900 DOI: 10.1002/pon.1030] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [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: 12/16/2022]
Abstract
Women who delay their presentation with breast cancer for three months or longer are more likely to be diagnosed with later stage disease and have poorer survival. Older women, who are at greater risk of developing breast cancer, are also more likely to delay their presentation. Factors associated with delayed presentation were assessed in 69 women (>65 years) with breast cancer. Previous factors identified for women of all ages were confirmed (having a non-lump symptom p=0.003) or strengthened (non-disclosure of symptom discovery to a relative or close friend p=0.001). Additional factors for delay in this older group included reservations about seeing their GP (p=0.02) and fear of the consequences of cancer (p=0.04). These factors should inform the design of interventions to reduce delays.
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Affiliation(s)
- C C Burgess
- Cancer Research UK London Psychosocial Group, Adamson Centre, St Thomas' Hospital, London SE1 7EH, UK.
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Stanley JK, Ramirez AJ, Mottaleb M, Chambliss CK, Brooks BW. Enantiospecific toxicity of the beta-blocker propranolol to Daphnia magna and Pimephales promelas. Environ Toxicol Chem 2006; 25:1780-6. [PMID: 16833138 DOI: 10.1897/05-298r1.1] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Propranolol is a widely prescribed, nonselective beta-adrenergic receptor-blocking agent. Propranolol has been detected in municipal effluents from the ng/L to the low-microg/L range. Like many therapeutics and other aquatic contaminants, propranolol is distributed as a racemic mixture ((R,S)-propranolol hydrochloride). Although the (S)-enantiomer is the most active form in mammals (up to 100-fold difference), no information is available regarding the enantiospecific toxicity of propranolol to aquatic organisms. Acute and chronic studies were conducted with Daphnia magna and Pimephales promelas to determine enantiospecific toxicity of propranolol to a model aquatic invertebrate and vertebrate, respectively. Also, enantiospecific effects of propranolol on D. magna heart rate were examined. Propranolol treatment levels were verified using high-performance liquid chromatography/mass spectrometry. Acute (48-h) responses of both organisms were similar for all enantiomer treatments. Chronic P. promelas responses to propranolol enantiomers followed the hypothesized relationship of (S)-propranolol being more toxic than (R)-propranolol, but chronic D. magna responses did not. This is potentially the result of a lack of beta-type receptors in cladocerans. No enantiospecific effects on daphnid heart rate were observed in acute exposures. Interestingly, some propranolol enantiomer treatments produced significant increases in reproduction before causing reproduction to decrease at higher treatment levels. To our knowledge, this research represents the first study of enantiospecific toxicity of chiral pharmaceutical pollutants.
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Affiliation(s)
- Jacob K Stanley
- Department of Biology, Baylor University, Waco, Texas 76798, USA.
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Westcombe AM, Gambles MA, Wilkinson SM, Barnes K, Fellowes D, Maher EJ, Young T, Love SB, Lucey RA, Cubbin S, Ramirez AJ. Learning the hard way! Setting up an RCT of aromatherapy massage for patients with advanced cancer. Palliat Med 2003; 17:300-7. [PMID: 12822844 DOI: 10.1191/0269216303pm769rr] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [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: 11/12/2022]
Abstract
Aromatherapy massage is used in cancer palliative care to improve quality of life but there is little evidence for its effectiveness. A large pragmatic multicentre randomized controlled trial was set up to examine the effectiveness of aromatherapy in improving psychological distress and quality of life in patients with cancer. This paper examines the challenges encountered in the design and execution of the study. The original design, i) focused on palliative care patients with advanced disease; ii) had both a no-intervention and a treatment control group (relaxation therapy); and iii) adopted 90% power for sample size calculations. A varied measurement strategy was employed. Recruitment proved difficult, referrers were 'gate-keeping', patients were often too ill to approach and others declined. The trial was modified to ensure viability. Eligibility was extended to all patients with cancer irrespective of stage, the relaxation group was removed and the power reduced to 80%. Although it is not generally good practice to change a study design once recruitment has started, the changes were consistent with the original basic study aims and design principles. The data collection phase was successfully completed in July 2002.
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Affiliation(s)
- A M Westcombe
- Marie Curie Palliative Care Research and Development Unit, Department of Psychiatry & Behavioural Sciences, Royal Free & University College Medical School, Hampstead, London, UK
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Abstract
The aim of this prospective study was to compare the prevalence of psychiatric morbidity following diagnosis of breast cancer between a group of women presenting with screen-detected cancer and a group presenting with symptomatic disease. Psychiatric symptoms were elicited using the Structured Clinical Interview (SCID) and classified according to DSM-III criteria. 61 (46%) of 132 women interviewed experienced an episode of psychiatric disorder between 1 month before diagnosis and 12 months post-diagnosis. There was no association between detection by screening of breast cancer and psychiatric disorder (Odds Ratio (OR) 0.8, 95% Confidence Interval (CI) 0.4-1.8 P=0.7). The occurrence of an episode of psychiatric disorder was associated with a previous history of treatment for psychological problems (OR 2.4, 95% CI 1.1-5.5, P=0.02). The results suggest there is no increased risk of developing psychiatric morbidity associated with the detection of cancer through the National Breast Screening Programme.
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Affiliation(s)
- C C Burgess
- Cancer Research UK London Psychosocial Oncology Group, Guy's King's & St Thomas' School of Medicine, 3rd Floor, South Wing, Adamson Centre for Mental Health, St Thomas' Hospital, SE1 7EH, London, UK.
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Grunfeld EA, Ramirez AJ, Hunter MS, Richards MA. Women's knowledge and beliefs regarding breast cancer. Br J Cancer 2002; 86:1373-8. [PMID: 11986766 PMCID: PMC2375381 DOI: 10.1038/sj.bjc.6600260] [Citation(s) in RCA: 158] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2001] [Revised: 02/15/2002] [Accepted: 02/25/2002] [Indexed: 01/07/2023] Open
Abstract
Approximately 20-30% of women delay for 12 weeks or more from self-discovery of a breast symptom to presentation to a health care provider, and such delay intervals are associated with poorer survival. Understanding the factors that influence patient delay is important for the development of an effective, targeted health intervention programme to shorten patient delay. The aim of the study was to elicit knowledge and beliefs about breast cancer among a sample of the general female population, and examine age and socio-economic variations in responses. Participants were randomly selected through the Postal Address File, and data were collected through the Office of National Statistics. Geographically distributed throughout the UK, 996 women participated in a short structured interview to elicit their knowledge of breast cancer risk, breast cancer symptoms, and their perceptions of the management and outcomes associated with breast cancer. Women had limited knowledge of their relative risk of developing breast cancer, of associated risk factors and of the diversity of potential breast cancer-related symptoms. Older women were particularly poor at identifying symptoms of breast cancer, risk factors associated with breast cancer and their personal risk of developing the disease. Poorer knowledge of symptoms and risks among older women may help to explain the strong association between older age and delay in help-seeking. If these findings are confirmed they suggest that any intervention programme should target older women in particular, given that advancing age is a risk factor for both developing breast cancer and for subsequent delayed presentation.
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Affiliation(s)
- E A Grunfeld
- Psychology Unit, Guy's, King's and St Thomas' Medical School, Guy's Campus, London SE1 9RT, UK.
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Burgess C, Hunter MS, Ramirez AJ. A qualitative study of delay among women reporting symptoms of breast cancer. Br J Gen Pract 2001; 51:967-71. [PMID: 11766868 PMCID: PMC1314188] [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: 02/23/2023] Open
Abstract
BACKGROUND Delayed presentation of symptomatic breast cancer of three months or more is associated with lower survival rates from the disease, yet 20% to 30% of women wait at least three months before consulting their general practitioner (GP) with breast symptoms. AIM To explore the factors that influence GP consultation by women with breast cancer symptoms. DESIGN OF STUDY Qualitative analysis of semi-structured interviews. SETTING Forty-six women with newly diagnosed breast cancer, selected from 185 women recruited to a larger study. METHOD Interviews were conducted eight weeks after diagnosis of breast cancer, comparing two groups of women divided according to the extent of delay between onset of symptoms and seeking medical care. Fifteen women had sought advice from their GP within two weeks of symptom discovery ('non-delayers' and 31 had waited 12 weeks or more before seeing their doctor ('delayers'). RESULTS Women with breast symptoms who presented promptly to GPs recognised the seriousness of the symptom they had discovered more quickly than delayers. Perception of seriousness was influenced by the nature of the initial symptom and how far it matched the individual's expectations of breast cancer as a painless breast lump. Other factors affecting help-seeking included attitudes to GP attendance, beliefs about the consequences of cancer treatment, and perceptions of other priorities taking precedence over personal health. CONCLUSIONS This analysis suggests that women need further information about the different types of breast cancer symptoms to assist symptom recognition, as well as encouragement to seek medical advice if a symptom is ambiguous. In addition, women may benefit from greater awareness of the benefits of early detection and reassurance about the improvements in quality of breast cancer care.
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Affiliation(s)
- C Burgess
- Adamson Centre for Mental Health, St Thomas's Hospital, London.
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Abstract
Lactic acid and trisodium phosphate (TSP) were evaluated for the ability to reduce Escherichia coli and aerobic plate counts (APCs) on lamb breasts that were inoculated with a lamb fecal paste. A 90-s water rinse was applied followed by either a 9-s (55 degrees C) 2% lactic acid spray, a 60-s (55 degrees C) 12% TSP dip, or a combined treatment of both lactic acid and TSP treatments. Lactic acid reduced E. coli and APCs by 1.6 log10/cm2, and TSP caused a 1.8-log10/cm2 reduction in E. coli and a 0.7-log10/cm2 reduction in APCs. Combined reductions by the lactic acid spray followed by the TSP dip were 1.8 and 1.5 log10/cm2 for E. coli and APCs, respectively. Lactic acid and trisodium phosphate, used alone or in combination, were effective in reducing numbers of E. coli and could be useful as pathogen intervention steps in lamb slaughter processing.
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Affiliation(s)
- A J Ramirez
- Department of Animal Science, Texas A&M University, College Station 77843-2471, USA
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Grunfeld EA, Ramirez AJ, Maher EJ, Peach D, Young T, Albery IP, Richards MA. Chemotherapy for advanced breast cancer: what influences oncologists' decision-making? Br J Cancer 2001; 84:1172-8. [PMID: 11336466 PMCID: PMC2363889 DOI: 10.1054/bjoc.2001.1733] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Chemotherapy is widely used in the management of patients with advanced breast cancer. However, a considerable proportion of patients experience toxic side effects without gaining benefit. This study aimed to elicit oncologists' views of the goals of chemotherapy for patients with advanced breast cancer and to elicit which factors are important in decisions to recommend chemotherapy to such patients. 30 oncologists underwent a semi-structured interview to examine their views of 5 goals of chemotherapy and of various disease, treatment and patient-related factors that might influence decisions to offer treatment. The clinicians also made decisions regarding treatment in relation to a hypothetical patient scenario under varying clinical conditions. Relief of symptoms and improvement of activity were rated as the most valuable and achievable goals of treatment. The patient's performance status, frailty and their wishes regarding treatment were the most important patient-related factors in determining decision-making. The most important disease/treatment-related factors were pace of the disease, previous poor response to chemotherapy, co-existing symptoms and concurrent medical conditions. The hypothetical scenario revealed that co-existing medical conditions, adverse previous response, increased age and depression would decrease the likelihood of recommending chemotherapy, whereas key symptoms (e.g. breathlessness) and the patient's goals would increase the likelihood. The findings suggest that British oncologists primarily aim to improve patients' physical function, although subjective factors, such as a patient's desire for anti-cancer treatment and their future goals, also influence decisions to offer treatment.
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Affiliation(s)
- E A Grunfeld
- ICRF Psychosocial Oncology Group, GKT Medical School, St Thomas' Hospital, London, SE1 7EH
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Abstract
BACKGROUND A new procedure to improve the accuracy of inulin assessment and renal glomerular filtration rate (GFR) avoiding urine sampling was compared and validated versus the reference procedure (with urine sampling and Anthrone reaction) in conscious unrestrained male Wistar rats. METHODS The hemodynamic study consisted of a priming dose of inulin (16 mg/kg) and para-aminohippurate (PAH; 8 mg/kg) followed by an infusion of inulin (36 mg/mL) and PAH (5.8 mg/mL) at a rate of 0.055 mL/min until steady-state conditions were reached (105 min). Inulin concentrations from samples were determined by a new enzymatic assay and Anthrone reaction. PAH concentrations were determined according to the standard method described by Smith et al. RESULTS A high correlation was found between GFR and renal blood flow (RBF) values calculated using the alternative (without urine sampling) and the reference (with urine sampling) clearance techniques (r = 0.98, P < 0.001, and r = 0.97, P < 0.001, respectively). Moreover, a significant and positive correlation between the values obtained from enzymatic and Anthrone inulin assessments was found (r = 0.99, P < 0.001). Likewise, the values of the 95% confidence interval (mean +/- 2 SD) for the enzymatic inulin assay showed a good agreement with those achieved with Anthrone (1.14 +/- 0.21 and 1.14 +/- 0.19 mL. min-1. 100 g-1 rat body weight, respectively). CONCLUSIONS This new approach has methodological and experimental advantages with respect to traditional procedures, making it a useful tool, not only for research purposes but also in the clinical setting.
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Affiliation(s)
- P A Fischer
- Section of Pharmacology, Department of Physiology, Favaloro University, Buenos Aires, Argentina
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Abstract
AIMS Consultant radiologists appear to be at greater risk of burnout than consultants working in other specialties. The aim of this study was to examine sources of stress and satisfaction at work for radiologists and hospital consultants in other specialties in order to try to understand this difference. MATERIALS AND METHODS A postal questionnaire survey of psychiatric morbidity (12-item General Health Questionnaire), burnout (Maslach Burnout Inventory) and sources of job stress and satisfaction (study-specific questionnaires) was carried out among a random sample of 882 hospital consultants working in radiology and three other specialties (surgery, gastroenterology and oncology). RESULTS The most stressful aspect of work for radiologists was work overload. Inadequacies in current staffing and facilities and concerns about funding were also major sources of stress, as were impositions made on radiologists by other clinicians. The most important sources of satisfaction for radiologists were their relationships with patients and being perceived to do their job well by colleagues. Importantly, radiologists reported less satisfaction than the other specialists from many of the aspects of work measured. A greater proportion of radiologists than other specialists felt insufficiently trained in communication skills [80% (n = 168) vs 47% (n = 310);P < 0.001] and management skills [84% (n = 179) vs 76% (n = 506);P < 0.05]. CONCLUSION These data highlight aspects of radiologists' work which need to be tackled in order to reduce their stress and increase their satisfaction, and thereby their risk of burnout.
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Affiliation(s)
- J Graham
- ICRF Psychosocial Oncology Group, Guy's, King's and St Thomas' School of Medicine, St Thomas' Campus, London, UK
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Abstract
OBJECTIVE The purpose of this study is to examine the influence of adverse life experiences and mood disorders on delayed presentation of breast cancer. METHODS One hundred fifty-eight patients were interviewed 5 months after diagnosis to assess the prevalence of adverse life events and difficulties using the Bedford College Life Events and Difficulties Schedule, and psychiatric morbidity using the Structured Clinical Interview (SCID) and DSM-III-R diagnostic criteria. RESULTS There was no association between experiencing a severe life event (p = 0.5) or difficulty, whether severe or nonsevere (p = 0.8), in the year preceding symptom discovery and patient delay. Counterintuitively, women who presented promptly to their GP (<12 weeks) with breast symptoms were more likely than those who delayed >/=12 weeks to report having a nonsevere event in the year before symptom discovery (p < 0.001). This appeared however, to be an artifact, because the women presenting promptly were recalling events that were closer in time to the research interview. Patient delay was not related to prevalence of depression (p = 0.2) or anxiety (p = 0.8) in the year preceding symptom discovery. CONCLUSION This study suggests that neither adverse life experiences nor mood disorder in the year before symptom discovery increase the risk of patients with symptoms of breast cancer delaying their presentation to a general practitioner.
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Affiliation(s)
- C C Burgess
- ICRF Psychosocial Oncology Group, Guy's, King's, and St. Thomas's Hospitals' School of Medicine, King's College, London, UK.
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Abstract
BACKGROUND Delayed presentation of symptomatic breast cancer is associated with lower survival. Understanding of the factors that influence delay is important for the development of strategies to shorten delays. We did a systematic review to assess the quality and strength of evidence on risk factors for delays by patients and providers. METHODS We generated hypotheses about the relation between each putative risk factor and delay, against which we tested studies. We did searches to identify papers containing original data related to risk factors for delays by patients (n=86) and providers (n=28). We critically appraised the papers for inclusion in the review according to predefined criteria. The small number of studies of adequate quality did not allow formal meta-analysis. We therefore assigned strength of evidence according to a combination of the number and size of studies supporting, not supporting, or refuting the hypotheses. FINDINGS Most studies were deemed to be of poor quality and were excluded. Among 23 studies of adequate quality, however, there was strong evidence for an association between older age and delay by patients, and strong evidence that marital status was unrelated to delays by patients. Younger age and presentation with a breast symptom other than a lump were strong risk factors for delays by providers. Moderate evidence was shown for several other factors. INTERPRETATION The strength of the current evidence is inadequate to inform the development of specific strategies to shorten delays by patients or providers. Clarification of the findings of this review through a major programme of primary research is urgently required.
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Affiliation(s)
- A J Ramirez
- ICRF Psychosocial Oncology Group, Guy's, King's and St Thomas's School of Medicine, Riddell House, St Thomas' Hospital, London, UK
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Abstract
BACKGROUND Most patients with breast cancer are detected after symptoms occur rather than through screening. The impact on survival of delays between the onset of symptoms and the start of treatment is controversial and cannot be studied in randomised controlled trials. We did a systematic review of observational studies (worldwide) of duration of symptoms and survival. METHODS We identified 87 studies (101,954 patients) with direct data linking delay (including delay by patients) and survival. We classified studies for analysis by type of data in the original reports: category I studies had actual 5-year survival data (38 studies, 53,912 patients); category II used actuarial or multivariate analyses (21 studies, 25,102 patients); and category III was all other types of data (28 studies, 22,940 patients). We tested the main hypothesis that longer delays would be associated with lower survival, and a secondary hypothesis that longer delays were associated with more advanced stage, which would account for lower survival. FINDINGS In category I studies, patients with delays of 3 months or more had 12% lower 5-year survival than those with shorter delays (odds ratio for death 1.47 [95% CI 1.42-1.53]) and those with delays of 3-6 months had 7% lower survival than those with shorter delays (1.24 [1.17-1.30]). In category II, 13 of 14 studies with unrestricted samples showed a significant adverse relation between longer delays and survival, whereas four of five studies of only patients with operable disease showed no significant relation. In category III, all three studies with unrestricted samples supported the primary hypothesis. The 13 informative studies showed that longer delays were associated with more advanced stage. In studies that controlled for stage, longer delay was not associated with shorter survival when the effect of stage on survival was taken into account. INTERPRETATION Delays of 3-6 months are associated with lower survival. These effects cannot be accounted for by lead-time bias. Efforts should be made to keep delays by patients and providers to a minimum.
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Affiliation(s)
- M A Richards
- ICRF Psychosocial Oncology Group, Guy's, King's and St Thomas's School of Medicine, St Thomas' Hospital, London, UK
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Abstract
The aim of this study was to examine the possible influence on survival of delays prior to presentation and/or treatment among women with breast cancer. Duration of symptoms prior to hospital referral was recorded for 2964 women who presented with any stage of breast cancer to Guy's Hospital between 1975 and 1990. Median follow-up is 12.5 years. The impact of delay (defined as having symptoms for 12 or more weeks) on survival was measured from the date of diagnosis and from the date when the patient first noticed symptoms to control for lead-time bias. Thirty-two per cent (942/2964) of patients had symptoms for 12 or more weeks before their first hospital visit and 32% (302/942) of patients with delays of 12 or more weeks had locally advanced or metastatic disease, compared with only 10% (210/2022) of those with delays of less than 12 weeks (P < 0.0001). Survival measured both from the date of diagnosis (P < 0.001) and from the onset of the patient's symptoms (P = 0.003) was worse among women with longer delays. Ten years after the onset of symptoms, survival was 52% for women with delays less than 12 weeks and 47% for those with longer delays. At 20 years the survival rates were 34% and 24% respectively. Furthermore, patients with delays of 12-26 weeks had significantly worse survival rates than those with delays of less than 12 weeks. Multivariate analyses indicated that the adverse impact of delay in presentation on survival was attributable to an association between longer delays and more advanced stage. However, within individual stages, longer delay had no adverse impact on survival. Analyses based on 'total delay (i.e. the interval between a patient first noticing symptoms and starting treatment) yielded very similar results in terms of survival to those based on delay to first hospital visit (delay in presentation).
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Affiliation(s)
- M A Richards
- ICRF Clinical and Psychosocial Oncology Groups, GKT School of Medicine, St Thomas' Hospital, London, UK
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Abstract
This study aimed to assess the proportion of patients with advanced breast cancer who report benefit from first-line palliative chemotherapy using a simple global measure of wellbeing and to identify factors predicting benefit. A consecutive series of women with advanced breast cancer undergoing first-line palliative chemotherapy was evaluated. The main outcome measure was patient report of overall wellbeing assessed at post-treatment interview. Physical, psychological and functional status were assessed using the Rotterdam Symptom Checklist (RSCL) on three occasions (pretreatment, at the start of the third cycle and post treatment). It was planned that treatment would be discontinued after six cycles (i.e. 18-24 weeks). One hundred and sixty patients started treatment, of whom 155 were assessable for quality of life. After treatment, 41 (26%) patients reported they felt better, 29 (19%) felt the same and 34 (22%) felt worse than they did before treatment. The other 51 (33%) patients either died or stopped attending the hospital before the post-treatment interview and were assigned as treatment 'failures'. Patients who reported feeling better after treatment had improvements in psychological distress (P < 0.0001), pain (P = 0.01), lack of energy (P = 0.02) and tiredness (P = 0.02), as well as improvement in functional status (P = 0.07). Feeling better was also correlated with disease response (P = 0.03). Feeling worse after treatment or treatment 'failure' was predicted by the pretreatment presence of a dry mouth (P = 0.003) and high levels of psychological distress (P = 0.03). Pretreatment lack of energy (P = 0.01), dry mouth (P = 0.02), presence of liver metastases (P = 0.03) and breathlessness (P = 0.03) predicted treatment 'failures'. The results of this study suggest that first-line palliative chemotherapy for advanced breast cancer confers benefit on a substantial proportion of patients, with about one-quarter feeling better after treatment and nearly a half feeling better or the same some 4-6 months after the start of treatment. Factors identified in this study may assist clinicians in deciding which patients should not be offered treatment, because of high risk of feeling worse or treatment 'failure'. This work now needs to be validated on a further cohort of women receiving chemotherapy for advanced breast cancer.
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Affiliation(s)
- A J Ramirez
- ICRF Psychosocial Oncology Group, UMDS, London, UK
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Abstract
This study aimed to examine the extent and determinants of patient and general practitioner delay in the presentation of breast cancer. One hundred and eighty-five cancer patients attending a breast unit were interviewed 2 months after diagnosis. The main outcome measures were patient delay in presentation to the general practitioner and non-referral by the general practitioner to hospital after the patient's first visit. Nineteen per cent of patients delayed > or = 12 weeks. Patient delay was related to clinical tumour size > or = 4 cm (P = 0.0002) and with a higher incidence of locally advanced and metastatic disease (P = 0.01). A number of factors predicted patient delay: initial breast symptom(s) that did not include a lump (OR 4.5, P = 0.003), not disclosing discovery of the breast symptom immediately to someone else (OR 6.0, P < 0.001), seeking help only after being prompted by others (OR 4.4, P = 0.007) and presenting to the general practitioner with a non-breast problem (OR 3.5, P = 0.03). Eighty-three per cent of patients were referred to hospital directly after their first general practitioner visit. Presenting to the GP with a breast symptom that did not include a lump independently predicted general practitioner delay (OR 3.6, P = 0.002). In view of the increasing evidence that delay adversely affects survival, a large multicentre study is now warranted to confirm these findings that may have implications for public and medical education.
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Affiliation(s)
- C C Burgess
- ICRF Psychosocial Oncology Group, United Medical School of Guy's Hospital, London, UK
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Abstract
This study evaluates junior house officers' perceptions of their communication skills with cancer patients; the usefulness of their undergraduate communication skills training; and their sources of emotional support. All 42 junior house officers employed at Guy's and Lewisham Hospitals in August 1994 were interviewed using a study-specific, semi-structured interview. Sixty-seven per cent of junior house officers felt they had adequate communication skills in relation to medical issues, but only 36% felt they had adequate skills in relation to psychological issues. Thirty-one per cent of doctors reported that they never, or nearly never, enquired about the emotional adjustment of dying patients. Lack of time was the most commonly reported reason for avoiding asking about psychological problems (62% of junior house officers), followed by wishing to avoid awkward questions (51%) and inadequacy of skills to deal with such issues (44%). Ninety-eight per cent of junior house officers had attended the 1-week undergraduate communication skills course at Guy's and St Thomas's Hospital Medical School (UMDS). Sixty-seven per cent of those who had attended found the course helpful and 62% felt they would benefit from further training as junior house officers. Seventy-four per cent felt they could discuss their work-related concerns with colleagues and 95% felt they could talk to friends. In contrast only about 9% felt they could, if needed, talk to a counsellor. Although the majority of the junior house officers reported benefit from their communication skills training, the course does not appear to be meeting all their communication training needs. Junior house officers require further training opportunities at the undergraduate and postgraduate levels. Traditional counselling services for junior house officers may not be meeting their support needs.
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Affiliation(s)
- B M Cantwell
- United Medical School of Guy's Hospital, London, UK
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Sanchez R, Gimenez MI, Ramos F, Baglivo H, Ramirez AJ. Non-modulating hypertension: evidence for the involvement of kallikrein/kinin activity associated with overactivity of the renin-angiotensin system. Successful blood pressure control during long-term Na+ restriction. J Hypertens 1996; 14:1287-91. [PMID: 8934356 DOI: 10.1097/00004872-199611000-00006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [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: 02/03/2023]
Abstract
BACKGROUND Non-modulating hypertensives are a subset of sodium-sensitive hypertensives characterized by a failure to modulate renal, vascular and adrenal glomerulosa responsivenesses to angiotensin II appropriately. OBJECTIVE To investigate the plasma renin activity (PRA) and urinary kallikrein-like activity (Ku) under different sodium conditions in essential hypertensive patients and in the modulating and non-modulating subsets of hypertensives. Additionally, in these groups of patients, the effects on blood pressure of a sustained Na+ restriction were evaluated. METHODS Fifteen normotensives (10 men, aged 29 +/- 5 years) and 54 untreated hypertensives (30 men, aged 34 +/- 7 years) were each administered subsequently three different diets containing 240, 140 and 50 mmol/day Na+, each diet for 10 days. At the end of each period, the PRA, Ku, 24 h urinary volume and urinary Na+ excretion were measured. Afterwards, the essential hypertensives were classified as 29 modulating essential hypertensives (MHT, 20 men, aged 32 +/- 7 years) and 25 non-modulating essential hypertensives (NMHT, 10 men, aged 36 +/- 8 years). Non-modulating ones were identified as individuals who failed to increase their effective renal plasma flow and to decrease their filtration fraction by at least 30% from baseline values, 10 days after changing from a low (10 mmol/day) to a high (260 mmol/day) Na+ intake. Blood pressure was measured with a Dinamap 8100 Critikon device. Both PRA and Ku were measured during normal Na+ intake by standard methods. Patients were administered a low-Na+ diet (10-50 mmol/day) for 12 months. RESULTS In essential hypertensives, Ku was lower under the three Na+ diets than it was in normotensives (P < 0.01) whereas the PRA was higher in hypertensives only during the low Na+ intake (P < 0.01). The non-modulating patients showed significantly higher PRA levels (4.0 +/- 0.8 ng ml h, P < 0.05) than did modulating ones (2.6 +/- 1.0 ng ml h) or normotensives (2.3 +/- 1.0 ng ml h). Conversely, non-modulating hypertensives had lower Ku (4.1 +/- 1.0 IU/24 h, P < 0.025) than did modulating ones (6.2 +/- 1.0 IU/24 h) or normotensives (7.8 +/- 2.0 IU/24 h). Blood pressure was significantly reduced during low Na+ intake only in normotensives (month 6: 143 +/- 4/94 +/- 2 mmHg; month 12: 139 +/- 5/89 +/- 3 mmHg) compared with baseline values (169 +/- 4/102 +/- 6 mmHg, P < 0.025). CONCLUSIONS It was shown that, in non-modulating hypertensives, in addition to an increased PRA, a reduced kallikrein-like activity coexists and seems to be associated with the impaired Na+ handling. Moreover, in these untreated patients the Na+ restriction was able to exert an antihypertensive effect even for long periods.
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Affiliation(s)
- R Sanchez
- Hospital Instituto de Cardiolögia, Academia Nacional de Medicine, Buenos Aires, Argentina
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Sanchez RA, Migliorini M, Giannone C, Ramirez AJ. Plasma renin activity levels influence the effect of converting enzyme inhibitors in preserving renal function in hypertension. J Hypertens 1996; 14:1025-31. [PMID: 8884559] [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: 02/02/2023]
Abstract
OBJECTIVE To study the effect of treatment with cilazapril versus nifedipine on the glomerular filtration rate (GFR), microalbumin excretion rate (mu Alb) and baseline plasma renin activity (PRA) levels in non-diabetic or diabetic essential hypertension. DESIGN AND METHODS Thirty-four moderate essential hypertensives and thirty-two type II diabetic hypertensives with currently normal renal function completed the study, receiving treatment with a converting enzyme inhibitor (CEI, 5-10 mg/day cilazapril) or a non-CEI (20-40 mg slow-release nifedipine three times a day) during a 12-month controlled follow-up study. RESULTS Either treatment induced a similar reduction in blood pressure. Patients with PRA > 3 ng/ml per h treated with cilazapril showed a proportional increase in GFR, whereas in those treated with a non-CEI there was a decline in GFR after 8 and 12 months. Only diabetic patients treated with cilazapril showed a mu Alb reduction associated with a stable GFR. CONCLUSION PRA predicts the effect of CEI preserving renal function in essential and diabetic hypertension.
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Affiliation(s)
- R A Sanchez
- Division of Hypertension, Hospital Instituto de Cardiologia-Academia Nacional de Medicina, Buenos Aires, Argentina
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Abstract
A national questionnaire-based survey has found that palliative physicians report lower levels of burnout and similar levels of psychiatric morbidity than those reported by consultants in other specialties. To try to explain these findings, this study compared the sources of job stress and satisfaction reported by consultant palliative physicians with those reported by consultants working in four other specialties: surgery, gastroenterology, radiology and oncology. Stressful and satisfying aspects of work were assessed using questionnaires designed specifically for the study. The response rate for the palliative physicians was 126/154 (82%) and for the consultants in the other specialties 882/1133 (78%). Palliative physicians reported that feeling overloaded and its effect on home life made the greatest contribution to their job stress, and having good relationships with patients, relatives and staff made the greatest contribution to their job satisfaction. However, compared with the other specialist groups, palliative physicians reported less stress from overload (p < 0.001) and more satisfaction from having good relationships (p < 0.001). They also reported less stress and more satisfaction with the way they are managed and resourced (both p < 0.001). Hospital-based palliative physicians reported more stress and less satisfaction from their management and resources than their colleagues working in hospices (both p = 0.05). Thirty-five percent of palliative physicians felt insufficiently trained in communication skills and 81% felt insufficiently trained in management skills. Burnout was more prevalent among consultants who felt insufficiently trained in communication and management skills than among those who felt sufficiently trained. It is important therefore that effective training in communication and management skills are provided and that, at the very least, existing levels of resourcing and management practices within palliative medicine are maintained in order that physicians working in the specialty are able to provide care to dying patients without prejudicing their own mental health.
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Affiliation(s)
- J Graham
- Imperial Cancer Research Fund Clinical Oncology Unit, Guy's Hospital, London, UK
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