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Lagerquist E, Al-Haddad BJS, Irvine J, Muskthel L, Rios A, Upadhyay K. Feeding volume advancement in preterm neonates: A level 4 neonatal intensive care unit quality improvement initiative. Nutr Clin Pract 2023; 38:1175-1180. [PMID: 37035908 DOI: 10.1002/ncp.10992] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 02/16/2023] [Accepted: 03/13/2023] [Indexed: 04/11/2023] Open
Abstract
INTRODUCTION Because of provider variability in feeding guideline application, a quality improvement (QI) initiative was begun to better standardize feeding initiation and advancement for preterm infants. Our specific, measurable, achievable, relevant, and timely aims included decreasing the time to reach full feeds by 35% and reducing the duration of central lines by 30% over 12 months in infants born between 25 and 30 weeks' gestation or with birth weight between 600 and 1250 g. METHODS Registered dietitians tracked central line days, parenteral nutrition (PN), enteral nutrition, fortification, guideline adherence, anthropometrics, necrotizing enterocolitis (NEC) cases, and central line-associated bloodstream infections (CLABSIs). QI progress charts were reviewed monthly. RESULTS Mean central line days decreased from 7.3 to 5.8. Days of PN decreased from 6.7 to 5.1. The day of life that enteral feeds were started decreased from 1.1 to 0.5. The number of days between starting enteral feeds and adding fortification decreased from 3.4 to 2.3 days. Full enteral feeds were achieved on average 2 days earlier. Birth weight was regained at around 10.2 days of life before the guideline was implemented and at a mean of 9.6 days after the guideline. There was no increase in cases of CLABSI or diagnoses of NEC. CONCLUSION After implementation of this feeding QI initiative at a level 4 neonatal intensive care unit, central line duration and PN use were decreased and infants reached full enteral feeds earlier without changes in cases of NEC, CLABSI, or time to regain birth weight.
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Affiliation(s)
- Eliza Lagerquist
- Department of Pediatrics, Division of Neonatology, University of Washington, Seattle, Washington, USA
| | - Benjamin J S Al-Haddad
- Department of Pediatrics, Division of Neonatology, University of Washington, Seattle, Washington, USA
- Department of Pediatrics, Division of Neonatology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Jill Irvine
- Department of Pediatrics, Division of Neonatology, University of Washington, Seattle, Washington, USA
| | - Lucy Muskthel
- Department of Pediatrics, Division of Neonatology, University of Washington, Seattle, Washington, USA
| | - Angel Rios
- Department of Pediatrics, Division of Neonatology, University of Washington, Seattle, Washington, USA
| | - Kirtikumar Upadhyay
- Department of Pediatrics, Division of Neonatology, University of Washington, Seattle, Washington, USA
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Kapur A, Boutin S, Lyster K, Irvine J, Sawchuk K. Retrospective application of the HEAR score on patients evacuated for chest pain: Assessing the utility of point-of-care troponin. Can J Rural Med 2022; 27:16-21. [PMID: 34975112 DOI: 10.4103/cjrm.cjrm_23_21] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Introduction The HEART scoring system codifies the clinical gestalt used by physicians with 0-2 points assigned to 5 criteria (history, electrocardiography, age, risk factors and troponin). This scoring provides a prognostic tool that assists in disposition planning. The use of a truncated HEART score, minus the troponin data (HEAR score), was used for patients presenting with chest pain at one of four outpost nursing stations served by La Ronge Health Centre in northern Saskatchewan. These nursing stations have no onsite physician and no ability to obtain any troponin data. This study set out to determine if there was any utility in conducting point-of-care (PoC) troponins in these nursing outposts. Materials and Methods A retrospective analysis was conducted using the La Ronge regional electronic medical record by searching for all patients for whom an outpost nurse had called a physician regarding chest pain symptoms between 01 January 2011 and 31 December 2016. The HEAR and HEART score were then calculated for each individual presentation of patients with chest pain that met inclusion and exclusion criteria. Results By calculating both the patient's HEART score before evacuation from the outposts and after (i.e. with the troponin data), we were able to determine that, in 89.4% of cases (110/123 events), patients would require evacuation regardless of the troponin values due to a HEART score ≥4. In 10.6% (13/124 events) of cases, the patients who were evacuated had a HEART score ≤3, and in only one case did the troponin data increase this score. Conclusions The majority of patients would continue to be evacuated regardless of the result of their PoC troponin due to an already elevated HEAR score. PoC troponin is unlikely to reduce the rate of evacuation of patients with chest pain from the nursing stations served by the La Ronge Health Centre.
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Affiliation(s)
- A Kapur
- Emergency Medicine, University of Saskatchewan, Regina, SK, Canada
| | - S Boutin
- Emergency Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - K Lyster
- Family Medicine, University of Saskatchewan, Regina, SK, Canada
| | - J Irvine
- Internal Medicine, Regina Qu'appelle Health Region, Regina, SK, Canada
| | - K Sawchuk
- Academic Family Medicine, University of Saskatchewan, LaRonge, SK, Canada
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Phipps WS, Greene DN, Pflaum H, Laha TJ, Dickerson JA, Irvine J, Merrill AE, Ranjitkar P, Henderson CM, Hoofnagle AN. Small volume retinol binding protein measurement by liquid chromatography-tandem mass spectrometry. Clin Biochem 2022; 99:111-117. [PMID: 34678307 PMCID: PMC8671195 DOI: 10.1016/j.clinbiochem.2021.10.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [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: 07/23/2021] [Revised: 10/13/2021] [Accepted: 10/17/2021] [Indexed: 01/03/2023]
Abstract
BACKGROUND The measurement of plasma concentrations of retinol binding protein is a component of nutritional assessment in neonatal intensive care. However, serial testing in newborns is hampered by the limited amount of blood that can be sampled. Limitations are most severe with preterm infants, for whom close monitoring may be most important. METHODS We developed an assay to quantify retinol binding protein using trypsin digestion and liquid chromatography-tandem mass spectrometry, which requires a serum or plasma volume of 5 µl. Additionally, we validated the method according to current recommendations and performed comparison with a standard nephelometry platform in clinical use. RESULTS The assay demonstrated linearity from below 1 mg/dL (0.48 µM) to more than 20 mg/dL (9.7 µM), and an imprecision of 11.8% at 0.43 mg/dL (0.21 µM). The distribution of results observed with the new method was different when compared with nephelometry. CONCLUSION Liquid chromatography-tandem mass spectrometry facilitated testing a smaller sample volume, thereby increasing the ability to monitor key nutritional markers in premature infants. The differences in results compared with a commercially-available nephelometric assay revealed questionable results for lower concentrations by immunoassay.
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Affiliation(s)
- William S. Phipps
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA
| | - Dina N. Greene
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA
| | - Hannah Pflaum
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA
| | - Thomas J. Laha
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA
| | - Jane A. Dickerson
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA,Seattle Children’s Hospital, Seattle, WA
| | - Jill Irvine
- University of Washington Medical Center, Seattle, WA
| | - Anna E. Merrill
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA
| | - Pratistha Ranjitkar
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA
| | - Clark M. Henderson
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA
| | - Andrew N. Hoofnagle
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA,Department of Medicine, University of Washington, Seattle, WA
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Pineles SL, Nillni YI, Pinna G, Irvine J, Webb A, Arditte Hall KA, Hauger R, Miller MW, Resick PA, Orr SP, Rasmusson AM. PTSD in women is associated with a block in conversion of progesterone to the GABAergic neurosteroids allopregnanolone and pregnanolone measured in plasma. Psychoneuroendocrinology 2018; 93:133-141. [PMID: 29727810 DOI: 10.1016/j.psyneuen.2018.04.024] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 03/28/2018] [Accepted: 04/23/2018] [Indexed: 12/29/2022]
Abstract
There is a need to identify new and more effective treatments for posttraumatic stress disorder (PTSD). Allopregnanolone and its stereoisomer pregnanolone (together termed ALLO) are metabolites of progesterone that positively and allosterically modulate GABA effects at GABAA receptors, thereby reducing anxiety and depression. Previous research revealed that women with PTSD had low cerebrospinal fluid (CSF) ALLO levels and a low ratio of ALLO to the allopregnanolone precursor 5α-DHP, consistent with deficient activity of the ALLO synthetic enzyme 3α-hydroxysteroid dehydrogenase (3α-HSD). The current study examined ALLO and the ratio of ALLO to 5α-DHP in plasma at rest and in response to psychophysiological stressors in trauma-exposed, medication-free women with and without PTSD. Participants were examined twice in random order during the early follicular phase (eFP) and mid-luteal phase (mLP) of the menstrual cycle. Plasma neurosteroids were measured using gas chromatography-mass spectrometry. Results indicate that the ALLO to 5α-DHP ratio in plasma increases between the eFP and mLP. In addition, women with PTSD have a lower ratio of ALLO to 5α-DHP than trauma-exposed healthy women, as well as blunted increases in this ratio in response to a moderately stressful laboratory procedure, i.e., differential fear conditioning, across the menstrual cycle. Clinically feasible testing for 3α-HSD dysfunction is critical to translating this line of research into clinical care. Measurement of this ratio in plasma could facilitate patient stratification in clinical treatment trials, as well as precision medicine targeting of treatments that address ALLO synthesis deficits in women with PTSD.
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Affiliation(s)
- S L Pineles
- National Center for PTSD, VA Boston Healthcare System, Boston, MA, 02130, USA; Department of Psychiatry, Boston University School of Medicine, Boston, MA, 02118, USA.
| | - Y I Nillni
- National Center for PTSD, VA Boston Healthcare System, Boston, MA, 02130, USA; Department of Psychiatry, Boston University School of Medicine, Boston, MA, 02118, USA
| | - G Pinna
- The Psychiatric Institute, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - J Irvine
- The Charles Stark Draper Laboratory, Inc., Cambridge, MA, 02139, USA
| | - A Webb
- The Charles Stark Draper Laboratory, Inc., Cambridge, MA, 02139, USA
| | - K A Arditte Hall
- National Center for PTSD, VA Boston Healthcare System, Boston, MA, 02130, USA; Department of Psychiatry, Boston University School of Medicine, Boston, MA, 02118, USA
| | - R Hauger
- Center of Excellence for Stress and Mental Health, San Diego VA Healthcare System, San Diego, CA, 9216, USA; Department of Psychiatry, University of California, San Diego, La Jolla, CA, 92093, USA
| | - M W Miller
- National Center for PTSD, VA Boston Healthcare System, Boston, MA, 02130, USA; Department of Psychiatry, Boston University School of Medicine, Boston, MA, 02118, USA
| | - P A Resick
- Department of Psychiatry and Behavioral Sciences, Duke University, Durham, NC, 27701, USA
| | - S P Orr
- Psychiatry Department, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, 02129, USA
| | - A M Rasmusson
- National Center for PTSD, VA Boston Healthcare System, Boston, MA, 02130, USA; Department of Psychiatry, Boston University School of Medicine, Boston, MA, 02118, USA
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Chillingworth S, Simpson A, Determann C, Ferguson C, Irvine J, Heaney S, Surgenor H. Safe extubation in recovery rooms. Anaesthesia 2015; 70:1100-1. [DOI: 10.1111/anae.13185] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Blom K, Baker B, How M, Dai M, Abbey S, Myers M, Abramson B, Irvine J, Perkins N, Tobe S. 904 Hypertension Analysis of Stress Reduction Using Mindfulness Meditation and Yoga: Results From a Randomized Controlled Trial. Can J Cardiol 2012. [DOI: 10.1016/j.cjca.2012.07.744] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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Nolan R, Irvine J, Durrani S, Lum-Kwong MM. 152 E-counseling is associated with therapeutic change in lifestyle and blood pressure in hypertension independent of symptoms of depression. Can J Cardiol 2011. [DOI: 10.1016/j.cjca.2011.07.109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022] Open
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Xin G, Long R, Guo X, Irvine J, Ding L, Ding L, Shang Z. Blood mineral status of grazing Tibetan sheep in the Northeast of the Qinghai–Tibetan Plateau. Livest Sci 2011. [DOI: 10.1016/j.livsci.2010.08.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Ritchie R, Khammy M, Bowden M, Irvine J, Andrews K, Huynh K, Kiriazis H, Kaye D, Venardos K. Diabetes-Induced Cardiac Dysfunction is Rescued by Endothelial Cationic Amino Acid Transporter 1 (CAT-1) Overexpression in Mice. Heart Lung Circ 2011. [DOI: 10.1016/j.hlc.2011.05.159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Omsjoe EH, Stien A, Irvine J, Albon SD, Dahl E, Thoresen SI, Rustad E, Ropstad E. Evaluating capture stress and its effects on reproductive success in Svalbard reindeer. CAN J ZOOL 2009. [DOI: 10.1139/z08-139] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Although many ecological studies of wild animal populations rely on capturing individuals at least once, few have investigated either the immediate stress responses of capture, restraint, and handling, or the longer term consequences on reproductive success. In this paper, we assume that the degree of stress increase with the time taken to capture and process an animal prior to release. The influence of time since onset of capture on body temperature and blood chemistry indicators of stress was investigated in 137 adult female Svalbard reindeer ( Rangifer tarandus platyrhynchus Vrolik, 1829) and 63 calves of both sexes captured by net in late-winter 2004 and 2005. In addition, we looked for evidence of negative effects of capture stress on reproductive success in marked animals over the period from 1995 to 2006. Body temperature increased with both chase time and the time the animals were restrained. In the latter case, body temperature increased twice as fast in nonpregnant animals (0.13 °C/min) compared with pregnant animals. Cortisol, glutamate dehydrogenase, and γ-glutamyltransferase all increased with time from onset of capture. However, the relationship for glucose with time since onset of capture increased initially before declining again. We found no evidence of a lower calving success in animals captured the previous winter when compared with animals that had not been captured the previous winter. Likewise, there was no relationship between the strength of the acute stress response (measured as cortisol concentrations) and the probability of pregnant females having a calf at foot the subsequent summer.
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Affiliation(s)
- E. H. Omsjoe
- Norwegian School of Veterinary Science, P.O. Box 8146, 0033 Oslo, Norway
- Norwegian Institute for Nature Research, NO-9296 Tromsø, Norway
- Macaulay Institute, Craigiebuckler, Aberdeen AB15 8QH, United Kingdom
| | - A. Stien
- Norwegian School of Veterinary Science, P.O. Box 8146, 0033 Oslo, Norway
- Norwegian Institute for Nature Research, NO-9296 Tromsø, Norway
- Macaulay Institute, Craigiebuckler, Aberdeen AB15 8QH, United Kingdom
| | - J. Irvine
- Norwegian School of Veterinary Science, P.O. Box 8146, 0033 Oslo, Norway
- Norwegian Institute for Nature Research, NO-9296 Tromsø, Norway
- Macaulay Institute, Craigiebuckler, Aberdeen AB15 8QH, United Kingdom
| | - S. D. Albon
- Norwegian School of Veterinary Science, P.O. Box 8146, 0033 Oslo, Norway
- Norwegian Institute for Nature Research, NO-9296 Tromsø, Norway
- Macaulay Institute, Craigiebuckler, Aberdeen AB15 8QH, United Kingdom
| | - E. Dahl
- Norwegian School of Veterinary Science, P.O. Box 8146, 0033 Oslo, Norway
- Norwegian Institute for Nature Research, NO-9296 Tromsø, Norway
- Macaulay Institute, Craigiebuckler, Aberdeen AB15 8QH, United Kingdom
| | - S. I. Thoresen
- Norwegian School of Veterinary Science, P.O. Box 8146, 0033 Oslo, Norway
- Norwegian Institute for Nature Research, NO-9296 Tromsø, Norway
- Macaulay Institute, Craigiebuckler, Aberdeen AB15 8QH, United Kingdom
| | - E. Rustad
- Norwegian School of Veterinary Science, P.O. Box 8146, 0033 Oslo, Norway
- Norwegian Institute for Nature Research, NO-9296 Tromsø, Norway
- Macaulay Institute, Craigiebuckler, Aberdeen AB15 8QH, United Kingdom
| | - E. Ropstad
- Norwegian School of Veterinary Science, P.O. Box 8146, 0033 Oslo, Norway
- Norwegian Institute for Nature Research, NO-9296 Tromsø, Norway
- Macaulay Institute, Craigiebuckler, Aberdeen AB15 8QH, United Kingdom
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Poyatos R, Martínez-Vilalta J, Cermák J, Ceulemans R, Granier A, Irvine J, Köstner B, Lagergren F, Meiresonne L, Nadezhdina N, Zimmermann R, Llorens P, Mencuccini M. Plasticity in hydraulic architecture of Scots pine across Eurasia. Oecologia 2007; 153:245-59. [PMID: 17453248 DOI: 10.1007/s00442-007-0740-0] [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] [Received: 07/03/2006] [Accepted: 03/21/2007] [Indexed: 10/23/2022]
Abstract
Widespread tree species must show physiological and structural plasticity to deal with contrasting water balance conditions. To investigate these plasticity mechanisms, a meta-analysis of Pinus sylvestris L. sap flow and its response to environmental variables was conducted using datasets from across its whole geographical range. For each site, a Jarvis-type, multiplicative model was used to fit the relationship between sap flow and photosynthetically active radiation, vapour pressure deficit (D) and soil moisture deficit (SMD); and a logarithmic function was used to characterize the response of stomatal conductance (G(s)) to D. The fitted parameters of those models were regressed against climatic variables to study the acclimation of Scots pine to dry/warm conditions. The absolute value of sap flow and its sensitivity to D and SMD increased with the average summer evaporative demand. However, relative sensitivity of G(s) to D (m/G (s,ref), where m is the slope and G(s,ref) is reference G(s) at D = 1 kPa) did not increase with evaporative demand across populations, and transpiration per unit leaf area at a given D increased accordingly in drier/warmer climates. This physiological plasticity was linked to the previously reported climate- and size-related structural acclimation of leaf to sapwood area ratios. G (s,ref), and its absolute sensitivity to D(m), tended to decrease with age/height of the trees as previously reported for other pine species. It is unclear why Scots pines have higher transpiration rates at drier/warmer sites, at the expense of lower water-use efficiency. In any case, our results suggest that these structural adjustments may not be enough to prevent lower xylem tensions at the driest sites.
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Affiliation(s)
- R Poyatos
- Institute of Earth Sciences Jaume Almera, ICTJA-CSIC, Lluís Solé i Sabarís, s/n, 08028 Barcelona, Spain.
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Ritvo P, Irvine J, Naglie G, Tomlinson G, Bezjak A, Matthew A, Trachtenberg J, Krahn M. Reliability and Validity of the PORPUS, a Combined Psychometric and Utility-Based Quality-of-Life Instrument for Prostate Cancer. J Urol 2006. [DOI: 10.1016/s0022-5347(05)00548-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- P. Ritvo
- York University and Cancer Care Ontario, Division of Preventive Oncology, Toronto, Ontario, Canada
| | - J. Irvine
- York University and Cancer Care Ontario, Division of Preventive Oncology, Toronto, Ontario, Canada
| | - G. Naglie
- York University and Cancer Care Ontario, Division of Preventive Oncology, Toronto, Ontario, Canada
| | - G. Tomlinson
- York University and Cancer Care Ontario, Division of Preventive Oncology, Toronto, Ontario, Canada
| | - A. Bezjak
- York University and Cancer Care Ontario, Division of Preventive Oncology, Toronto, Ontario, Canada
| | - A. Matthew
- York University and Cancer Care Ontario, Division of Preventive Oncology, Toronto, Ontario, Canada
| | - J. Trachtenberg
- York University and Cancer Care Ontario, Division of Preventive Oncology, Toronto, Ontario, Canada
| | - M. Krahn
- York University and Cancer Care Ontario, Division of Preventive Oncology, Toronto, Ontario, Canada
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Irvine J, Law BE, Kurpius MR, Anthoni PM, Moore D, Schwarz PA. Age-related changes in ecosystem structure and function and effects on water and carbon exchange in ponderosa pine. Tree Physiol 2004; 24:753-763. [PMID: 15123447 DOI: 10.1093/treephys/24.7.753] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
As forests age, their structure and productivity change, yet in some cases, annual rates of water loss remain unchanged. To identify mechanisms that might explain such observations, and to determine if widely different age classes of forests differ functionally, we examined young (Y, approximately 25 years), mature (M, approximately 90 years) and old (O, approximately 250 years) ponderosa pine (Pinus ponderosa Dougl. ex P. Laws.) stands growing in a drought-prone region of central Oregon. Although the stands differed in tree leaf area index (LAIT) (Y = 0.9, M = 2.8, O = 2.1), cumulative tree transpiration measured by sap flow did not differ substantially during the growing season (100-112 mm). Yet when water was readily available, transpiration per unit leaf area of the youngest trees was about three times that of M trees and five times that of O trees. These patterns resulted from a nearly sixfold difference in leaf specific conductance (KL) between the youngest and oldest trees. At the time of maximum transpiration in the Y stand in May-June, gross carbon uptake (gross ecosystem production, GEP) was similar for Y and O stands despite an almost twofold difference in stand leaf area index (LAIS). However, the higher rate of water use by Y trees was not sustainable in the drought-prone environment, and between spring and late summer, KL of Y trees declined fivefold compared with a nearly twofold decline for M trees and a < 30% reduction in O trees. Because the Y stand contained a significant shrub understory and more exposed soil, there was no appreciable difference in mean daily latent energy fluxes between the Y stand and the older stands as measured by the eddy-covariance technique. These patterns resulted in 60 to 85% higher seasonal GEP and 55 to 65% higher water-use efficiency at the M and O stands compared with the Y stand.
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Affiliation(s)
- J Irvine
- College of Forestry, Oregon State University, Corvallis, OR 97331, USA.
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Ma HM, Schulze S, Lee S, Yang M, Mirkov E, Irvine J, Moore P, Paterson A. An EST survey of the sugarcane transcriptome. Theor Appl Genet 2004; 108:851-863. [PMID: 14647901 DOI: 10.1007/s00122-003-1510-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2003] [Accepted: 09/30/2003] [Indexed: 05/24/2023]
Abstract
Its large genome and high polyploidy makes sugarcane (Saccharum spp.) a singularly challenging crop to study and improve using genetic approaches. To provide large numbers of functionally characterized candidate genes that might be tested for direct association (rather than distant linkage) with economically important traits, we sequenced the 5' ends of 9,216 clones from three cDNA libraries (apex, leaf and mature internode), representing 3,401 non-redundant sequences. About 57% of these sequences could be assigned a tentative function based on statistically significant similarity to previously characterized proteins or DNA sequences. Another 28% corresponded to previously identified, but uncharacterized, sequences. Some of the remaining unidentified sequences were predicted to be genes which could potentially be new to plants or unique to sugarcane. Comparisons of the sugarcane ESTs to a large sorghum EST database revealed similar compositions of expressed genes between some different tissues. Comparison to a detailed Arabidopsis protein database showed some highly conserved sequences, which might be useful DNA markers for pan-angiosperm comparative mapping. These EST sequences provide a foundation for many new studies to accelerate isolation of agronomically important genes from the cumbersome sugarcane genome.
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Affiliation(s)
- H-M Ma
- Plant Genome Mapping Laboratory, University of Georgia, 111 Riverbend Rd., Athens, GA 30602, USA
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Tracey A, Bunton D, Irvine J, MacDonald A, Shaw AM. Relaxation to bradykinin in bovine pulmonary supernumerary arteries can be mediated by both a nitric oxide-dependent and -independent mechanism. Br J Pharmacol 2002; 137:538-44. [PMID: 12359636 PMCID: PMC1573515 DOI: 10.1038/sj.bjp.0704890] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
1. The aim of the present study was to determine the relative contribution of prostanoids, nitric oxide and K(+) channels in the bradykinin-induced relaxation of bovine pulmonary supernumerary arteries. 2. In endothelium-intact, but not denuded rings, bradykinin produced a concentration-dependent relaxation (pEC(50), 9.6+/-0.1), which was unaffected by the cyclo-oxygenase inhibitor indomethacin. The nitric oxide scavenger hydroxocobalamin (200 micro M, pEC(50), 8.5+/-0.2) and the nitric oxide synthase inhibitor L-NAME (100 micro M, pEC(50), 8.9+/-0.1) and the combination of L-NAME and hydroxocobalamin (pEC(50), 8.1+/-0.2) produced rightward shifts in the bradykinin concentration response curve. 3. The guanylyl cyclase inhibitor ODQ (10 micro M, pEC(50), 9.6+/-0.4) did not affect the response to bradykinin. 4. Elevating the extracellular [K(+)] to 30 mM did not affect the response to bradykinin but abolished the response when ODQ or L-NAME was present. 5. The K(+) channel blocker apamin (100 nM), combined with charybdotoxin (100 nM), produced a small reduction in the maximum response to bradykinin but they abolished the response to bradykinin when ODQ, L-NAME or hydroxocobalamin were present. Apamin (100 nM) combined with iberiotoxin (100 nM) also reduced the response to bradykinin in the presence of hydroxocobalamin or L-NAME. 6. The concentration response curve for sodium nitroprusside-induced relaxation was abolished by ODQ (10 micro M) and shifted to the right by apamin and charybdotoxin. 7. These studies suggest that in bovine pulmonary supernumerary arteries bradykinin can stimulate the formation of nitric oxide and activate an EDHF-like mechanism and that either of these pathways alone can mediate the bradykinin-induced relaxation. In addition nitric oxide, acting through guanylyl cyclase, can activate an apamin/charbydotoxin-sensitive K(+) channel in this tissue.
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Affiliation(s)
- A Tracey
- School of Biological & Biomedical Sciences, Glasgow Caledonian University, City Campus, Cowcaddens Road, Glasgow G4 OBA
| | - D Bunton
- School of Biological & Biomedical Sciences, Glasgow Caledonian University, City Campus, Cowcaddens Road, Glasgow G4 OBA
| | - J Irvine
- School of Biological & Biomedical Sciences, Glasgow Caledonian University, City Campus, Cowcaddens Road, Glasgow G4 OBA
| | - A MacDonald
- School of Biological & Biomedical Sciences, Glasgow Caledonian University, City Campus, Cowcaddens Road, Glasgow G4 OBA
| | - A M Shaw
- School of Biological & Biomedical Sciences, Glasgow Caledonian University, City Campus, Cowcaddens Road, Glasgow G4 OBA
- Author for correspondence:
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17
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Perks MP, Irvine J, Grace J. Canopy stomatal conductance and xylem sap abscisic acid (ABA) in mature Scots pine during a gradually imposed drought. Tree Physiol 2002; 22:877-883. [PMID: 12184977 DOI: 10.1093/treephys/22.12.877] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We investigated the effect of drought on canopy stomatal conductance (g(c)), and examined the hypothesis that g(c) is controlled by the chemical messenger abscisic acid (ABA) produced in roots. Beginning in November 1994, we subjected a mature stand of Scots pine (Pinus sylvestris L.) to an imposed 11-month drought. Control plots were maintained at average-season soil water content. Xylem sap was extracted from shoots at regular intervals from April to November 1995. Soil water, sap flow and leaf water potentials (predawn to dusk) were recorded at the same time. Canopy stomatal conductance was calculated from sap flow data and xylem sap ABA concentrations ([ABA(xyl)]) were measured by radioimmunoassay. Mean [ABA(xyl)] in control trees was 250 micromol m(-3). No diurnal variation in [ABA(xyl)] was detected. With soil drying, [ABA(xyl)] increased to a maximum in summer (600 micromol m(-3)), but decreased again toward autumn; however, no significant increase in ABA flux to the leaves occurred. A decline in g(c) was detected when volumetric soil water content declined below 0.12. The decline in g(c) could not have been mediated by increasing [ABA(xyl)] because stomatal closure appeared to precede any increase in [ABA(xyl)]. Peak sap flow velocity data were used to estimate delivery times for root-to-shoot signals in 15-m tall trees. Under normal field conditions, a signal would take 12 days to travel from the site of production (roots) to the presumed site of action (shoots). However, under drought conditions it may take a chemical signal in excess of 6 weeks. We conclude that a feedforward model of short-term stomatal response to soil drying, based solely on the action of a chemical messenger from the roots, is not applicable in mature conifer trees because signal transmission is too slow.
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Affiliation(s)
- M P Perks
- Institute of Ecology and Resource Management, University of Edinburgh, UK.
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18
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Abstract
We investigated the impact of seasonal soil water deficit on the processes driving net ecosystem exchange of carbon (NEE) in old-growth and recently regenerating ponderosa pine (Pinus ponderosa Doug. ex Laws.) stands in Oregon. We measured seasonal patterns of transpiration, canopy conductance and NEE, as well as soil water, soil temperature and soil respiration. The old-growth stand (O) included two primary age classes (50 and 250 years), had a leaf area index (LAI) of 2.1 and had never been logged. The recently regenerating stand (Y) consisted predominantly of 14-year-old ponderosa pine with an LAI of 1.0. Both stands experienced similar meteorological conditions with moderately cold wet winters and hot dry summers. By August, soil volumetric water content within the upper 30 cm had declined to a seasonal minimum of 0.07 at both sites. Between April and June, both stands showed similar rates of transpiration peaking at 0.96 mm day(-1); thereafter, trees at the Y site showed increasing drought stress with canopy stomatal resistance increasing 6-fold by mid-August relative to values for trees at the O site. Over the same period, predawn water potential (psi(pd)) of trees at the Y site declined from -0.54 to -1.24 MPa, whereas psi(pd) of trees at the O site remained greater than -0.8 MPa throughout the season. Soil respiration at the O site showed a strong seasonal correlation with soil temperature with no discernible constraints imposed by declining soil water. In contrast, soil respiration at the Y site peaked before seasonal maximal soil temperatures and declined thereafter with declining soil water. No pronounced seasonal pattern in daytime NEE was observed at either site between April and September. At the Y site this behavior was driven by concurrent soil water limitations on soil respiration and assimilation, whereas there was no evidence of seasonal soil water limitations on either process at the O site.
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Affiliation(s)
- J Irvine
- College of Forestry, Oregon State University, Corvallis, OR 97331, USA
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19
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Ritvo P, Irvine J, Robinson G, Brown L, Murphy KJ, Matthew A, Rosen B. Psychological adjustment to familial-genetic risk assessment for ovarian cancer: predictors of nonadherence to surveillance recommendations. Gynecol Oncol 2002; 84:72-80. [PMID: 11748980 DOI: 10.1006/gyno.2001.6461] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE To evaluate whether self-report measures of psychological distress and perceived risk were associated with nonadherence to recommended ovarian cancer surveillance. METHODS Eighty-three patients attending the Familial Ovarian Cancer Clinic (FOCC) at Princess Margaret Hospital were assessed psychosocially prior to and during initial familial-genetic assessment and then monitored for adherence with recommended follow-up surveillance over a period of 12-18 months. The assessment protocol included an investigator-designed clinic questionnaire, the State-Trait Anxiety Inventory (STAI), Center for Epidemiologic Studies Depression Scale (CESD), Life Orientation Test (LOT), Medical Outcomes Study Social Support Survey (MOSSS), Texas Inventory of Grief, and the COPE. Nonadherence was measured in terms of unexplained absences at one or two recommended and scheduled surveillance appointments following the familial-genetic assessment. RESULTS Univariate tests revealed a significant association between higher perception of ovarian cancer risk, as assessed immediately after the familial-genetic risk assessment in the clinic and nonadherence to physician-recommended surveillance (chi2 (2, N = 83) = 9.75, P < 0.008). Empirically based estimates of risk, conveyed by the clinic team to subjects, were not significantly associated with nonadherence (chi2 (2, N = 83) = 0.19, P = 0.91). Logistic regression analysis revealed that subjects who perceived themselves to be at high ovarian cancer risk were five times more likely to be nonadherent than participants who perceived themselves to be at low or medium ovarian cancer risk. CONCLUSIONS These results suggest that higher self-perceived risk may predict adherence difficulties to recommended surveillance in women attending a familial-genetic risk clinic.
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Affiliation(s)
- P Ritvo
- Toronto General Hospital, Ontario Cancer Institute/University Health Network, Toronto, Ontario, M5G 2C4, Canada.
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20
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Stewart DE, Rosen B, Irvine J, Ritvo P, Shapiro H, Murphy J, Thomas J, Robinson GE, Neuman J, Deber R. The disconnect: infertility patients' information and the role they wish to play in decision making. Medscape Womens Health 2001; 6:1. [PMID: 11547268] [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] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
OBJECTIVE To determine the preferred role in medical decision making of women undergoing fertility treatments and to establish whether their knowledge of treatments is adequate to inform their choices. METHODS Self-report survey of 404 women undergoing fertility treatments in 2 university hospitals and a private fertility clinic in Canada. RESULTS The women had been in fertility treatment for 2.3 +/- 2.6 years; 67.8% reported taking fertility drugs. Most (61.7%) women wanted to share knowledge equally with their doctors about possible fertility treatments. However, about half wanted to decide alone or mostly by themselves about the acceptability of treatment risks and benefits (56%), what treatments should be selected (49.8%), and when to conclude treatments (54.3%). In addition, 55.1% of the women did not know their personal eventual chances of pregnancy with fertility treatment or thought it was 50% or greater. Over half of the women (57.2%) who had taken fertility drugs were unaware of a possible link between fertility drugs and increased ovarian cancer risk. The majority of women (61.8%) who knew of this possible association reported that they learned about it from the print media. Women who knew of the association had a poor understanding of the strength of the evidence or the ability to detect or treat ovarian cancer successfully, and 88.3% thought they could reduce cancer risk by following their doctors' advice. CONCLUSIONS Despite these women's wishes to actively participate in fertility treatment decisions, they lacked the necessary information to do so meaningfully. Public health policymakers, professional and advocacy organizations, physicians, other healthcare providers, and women themselves must find ways to improve the general public's and patients' understanding about fertility treatment outcomes and risks.
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Affiliation(s)
- D E Stewart
- University of Toronto, Department of Obstetrics and Gynecology, Canada
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21
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Abstract
The aim of this study was to determine whether learned helplessness, cognitive distortions, self-efficacy, and dispositional optimism assessed at Time 1 (T1; questionnaires mailed at 1 month postdischarge) would predict depressive symptoms at Time 2 (T2; questionnaires mailed at 1-year follow-up) in a sample of 86 patients hospitalized with ischemic heart disease. Multiple regression results indicated that optimism and cognitive distortions at T1 were significantly associated with T1 depressive symptoms after controlling for confounding variables. When the T1 psychological factors were analyzed with T2 depressive symptoms, only optimism continued to predict depressive symptoms after controlling for confounds and T1 depressive symptoms. The global expectancies that optimism assessed appeared to be more stable over time than the statelike beliefs of cognitive distortions and may have accounted for why optimism predicted T2 depressive symptoms.
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Affiliation(s)
- Z M Shnek
- Department of Psychology, Credit Valley Hospital, Mississauga, Ontario, Canada.
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22
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McAlister FA, Levine M, Zarnke KB, Campbell N, Lewanczuk R, Leenen F, Rabkin S, Wright JM, Stone J, Feldman RD, Lebel M, Honos G, Fodor G, Burgess E, Tobe S, Hamet P, Herman R, Irvine J, Culleton B, Petrella R, Touyz R. The 2000 Canadian recommendations for the management of hypertension: Part one--therapy. Can J Cardiol 2001; 17:543-59. [PMID: 11381277] [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: 02/20/2023] Open
Abstract
OBJECTIVE To provide updated, evidence-based recommendations for the therapy of hypertension in adults. OPTIONS For patients with hypertension, there are a number of lifestyle manoeuvres and antihypertensive agents that may control blood pressure. Randomized trials evaluating first- line therapy with thiazides, beta-adrenergic antagonists, angiotensin-converting enzyme inhibitors, calcium channel blockers, alpha-blockers, centrally acting agents or angiotensin II receptor antagonists were reviewed. OUTCOMES The health outcomes considered were changes in blood pressure, cardiovascular morbidity, and cardiovascular and/or all-cause mortality rates. Economic outcomes were not considered due to insufficient evidence. EVIDENCE Medline searches were conducted from the period of the last revision of the Canadian Recommendations for the Management of Hypertension (May 1998 to October 2000). Reference lists were scanned, experts were polled, and the personal files of the subgroup members and authors were used to identify other studies. All relevant articles were reviewed and appraised, using prespecified levels of evidence, by content experts and methodological experts. VALUES A high value was placed on the avoidance of cardiovascular morbidity and mortality. BENEFITS, HARMS, AND COSTS Various lifestyle manoeuvres and antihypertensive agents reduce the blood pressure of patients with sustained hypertension. In certain settings, and for specific classes of drugs, blood pressure lowering has been associated with reduced cardiovascular morbidity and/or mortality. RECOMMENDATIONS The present document contains detailed recommendations pertaining to all aspects of the therapy of patients with hypertension, including lifestyle modifications proven to lower blood pressure, treatment thresholds, target blood pressures, choice of agents in various settings and strategies to enhance adherence. Lower thresholds for blood pressure treatment are advocated for people with other cardiovascular risk factors or established hypertensive target organ damage. Implicit in the recommendations for therapy is the principle that treatment should be individualized for each patient and the choice of agent should be dictated by coexistent conditions. For the treatment of uncomplicated essential hypertension, thiazides, beta-adrenergic antagonists, angiotensin-converting enzyme inhibitors or calcium channel blockers may be appropriate, depending on individual circumstances. VALIDATION All recommendations were graded according to strength of the evidence and voted on by the Canadian Hypertension Recommendations Working Group. Only those recommendations achieving high levels of consensus are reported here. These guidelines will be updated annually.
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Affiliation(s)
- F A McAlister
- Division of General Internal Medicine, University of Alberta, Edmonton, Canada.
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23
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Abstract
The aim of this study was to determine whether learned helplessness, cognitive distortions, self-efficacy, and dispositional optimism assessed at Time 1 (T1; questionnaires mailed at 1 month postdischarge) would predict depressive symptoms at Time 2 (T2; questionnaires mailed at 1-year follow-up) in a sample of 86 patients hospitalized with ischemic heart disease. Multiple regression results indicated that optimism and cognitive distortions at T1 were significantly associated with T1 depressive symptoms after controlling for confounding variables. When the T1 psychological factors were analyzed with T2 depressive symptoms, only optimism continued to predict depressive symptoms after controlling for confounds and T1 depressive symptoms. The global expectancies that optimism assessed appeared to be more stable over time than the statelike beliefs of cognitive distortions and may have accounted for why optimism predicted T2 depressive symptoms.
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Affiliation(s)
- Z M Shnek
- Department of Psychology, Credit Valley Hospital, Mississauga, Ontario, Canada.
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24
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Shaw AM, Brown C, Irvine J, Bunton DC, MacDonald A. Role of the 5-HT(2A)receptor and alpha(1)-adrenoceptor in the contractile response of rat pulmonary artery to 5-HT in the presence and absence of nitric oxide. Pulm Pharmacol Ther 2001; 13:277-85. [PMID: 11061982 DOI: 10.1006/pupt.2000.0255] [Citation(s) in RCA: 8] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study investigated the role of 5-HT(2A)receptors and alpha(1)-adrenoceptors in the contractile response to 5-HT in the first branch pulmonary artery of the rat and their interaction with endogenous nitric oxide. 5-HT and phenylephrine induced concentration-dependent contractions. The alpha(1)-adrenoceptor antagonists prazosin, HV723 and phentolamine produced concentration-dependent rightward shifts of the 5-HT concentration-response curves (CRC) consistent with an action at alpha(1)-adrenoceptors. The 5-HT(2)receptor antagonists ritanserin, ketanserin and methysergide produced rightward shifts that were less than would have been predicted for an action solely at 5-HT(2A)receptors. 5-HT and phenylephrine CRCs were shifted to the left by l -NAME. Endothelium denudation also increased the tissue sensitivity to 5-HT. In the presence of l -NAME, ketanserin produced greater antagonism of the 5-HT CRC but not the phenylephrine CRC. Ketanserin also produced greater antagonism of the 5-HT CRC in endothelium denuded rings compared with endothelium intact rings. These findings indicate (a) that both the alpha(1)-adrenoceptor class and the 5-HT(2A)receptor is involved in the contractile response to 5-HT; (b) in the presence of endogenous nitric oxide the contractile response to 5-HT is mediated predominently by alpha(1)-adrenoceptors; (c) inhibition of endogenous nitric oxide potentiates the 5-HT(2A)receptor-mediated component of the contraction.
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Affiliation(s)
- A M Shaw
- School of Biological and Biomedical Sciences, Glasgow Caledonian University, Glasgow, G4 0BA, UK.
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25
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Shaw AM, Bunton DC, Brown T, Irvine J, MacDonald A. Regulation of sensitivity to 5-hydroxytryptamine in pulmonary supernumerary but not conventional arteries by a 5-HT(1D)-like receptor. Eur J Pharmacol 2000; 408:69-82. [PMID: 11070185 DOI: 10.1016/s0014-2999(00)00757-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Bovine pulmonary supernumerary arteries are more sensitive to 5-hydroxtryptamine (5-HT) (pD(2) 6.43+/-0.25) than conventional arteries (pD(2) 5.32+/-0.16). This study investigated receptors for 5-HT in ring segments of these arteries. The 5-HT(2) receptor agonist, 2,5 dimethoxy-4-iodoamphetamine hydrobromide (DOI) constricts both arteries. The selective 5-HT(2) receptor antagonist ritanserin produced insurmountable antagonism of 5-HT concentration-response curves in both arteries, whereas the 5-HT(1B/1D) receptor antagonist N-[4-methoxy-3-(4-methyl-1-piperazinyl)phenyl]-2'-methyl-4'(5-methyl- 1,2,4-oxadiazol-3-yl[1,1,-biphenyl]-4-carboxamide hydrochloride (GR127935) produced much greater antagonism in supernumerary arteries. In rings preconstricted with 9,11-dideoxy-9, 11-methanoepoxy prostalagdin F(2alpha) (U46619) and relaxed with the adenylyl cyclase activator forskolin, the selective 5-HT(ID) receptor agonist 2-[5-[3-(4-methylsulphonylamino) benzyl-1,2, 4-oxadiazol-5-yl]-1H-indole-3-yl] ethylamine (L694247) reversed the relaxation. Concentration-response curves for L694247-induced reversal of forskolin-relaxation were antagonised by GR127935 in supernumerary (pK(B) 8.6) and conventional (pK(B) 8.4) arteries, whereas concentration-response curves to 5-HT-were less sensitive to antagonism by GR127935T and this was more obvious in conventional (pK(B) 7.6) than supernumerary (pK(B) 8.1) arteries. Neither the selective 5-HT(1D) receptor antagonist (1-(3-chlorophenyl)-4-[3, 3-diphenyl (2-(S,R) hydroxypropanyl)piperazine] hydrochloride (BRL15572) nor the 5-HT(1B) receptor antagonist (2,3,6, 7-tetrahydro-1'-methyl-5-[2'methyl-4'5-(methyl-1,2,4-oxadiazol-3-y l) biphenyl-4-carbonyl]furo[2,3-f]indole-3-spiro-4'-piperidine hydrochloride (SB224289) antagonised concentration-response curves induced by 5-HT or 5-HT(1)-receptor-selective agonists. In addition to the 5-HT(2A) receptor, 5-HT activates a GR127935-sensitive and a GR127935-insensitive receptor in these arteries. Supernumerary arteries have a greater proportion of GR127935-sensitive receptors, which display only some of the pharmacological characteristics of the cloned 5-HT(ID) receptor. It is possible that the GR127935-sensitive receptor could be a species homologue of the human 5-HT(1B) receptor that is insensitive to SB224289.
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Affiliation(s)
- A M Shaw
- School of Biological and Biomedical Sciences, Glasgow Caledonian University, Cowcaddens Rd., Glasgow, G4 OBA, UK.
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26
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Abstract
The specific objectives of this report were to determine (1) the usual practice of vascular surgeons with respect to risk factor inquiry and intervention, (2) which risk factors are endorsed by vascular surgeons as being very important in the management of patients with PAD, and, finally, (3) which risk factors vascular surgeons are confident in managing.
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Affiliation(s)
- P G Kalman
- Department of Surgery, University of Toronto, ON, Canada
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27
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Abstract
The regression-based general image-quality equation (GIQE) previously developed for visible imagery was extended to IR imagery. The equation predicts IR National Imagery Interpretability Rating Scale values as a function of scale, sharpness, and signal-to-noise ratio with the same form as the visible GIQE.
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Affiliation(s)
- J C Leachtenauer
- J/M Leachtenauer Associates, Incorporated, 4208 Wakefield Drive, Annandale, Virginia 22003, USA.
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28
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Krahn M, Ritvo P, Irvine J, Tomlinson G, Bezjak A, Trachtenberg J, Naglie G. Construction of the Patient-Oriented Prostate Utility Scale (PORPUS): a multiattribute health state classification system for prostate cancer. J Clin Epidemiol 2000; 53:920-30. [PMID: 11004418 DOI: 10.1016/s0895-4356(00)00211-0] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Health status indexes, such as the EuroQol, consist of a health state classification system and a set of utility weights. Indexes measure quality of life using a 0-1 utility score. Utilities for outcomes in prostate cancer (PC) are of unique importance, but generic indexes do not represent PC outcomes (e.g., sexual, urinary, bowel dysfunction) well, and may not capture their full impact. As a step toward improved utility measurement, we constructed a classification system for PC. We generated items for each of six health domains and rated their importance using interviews with 10 clinical experts and 80 patients. Key concepts were selected for each domain using item importance weightings, and a set of predetermined criteria. Text was developed to express levels of severity within each domain. Experts and two additional groups of patients (n = 40, n = 96) evaluated textual clarity and endorsed the content validity of the instrument. The final system consists of 10 domains with 4-6 levels each. The content validity of the system was endorsed by patients and experts. In conjunction with a set of utility weights, it may be used to develop a health status index, to improve utility measurement in patients, and to serve as a short psychometric (nonutility) instrument.
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Affiliation(s)
- M Krahn
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada.
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29
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Sandor P, Baker B, Irvine J, Dorian P, McKessok D, Mendlowitz S. Effectiveness of fluoxetine and doxepin in treatment of melancholia in depressed patients. Depress Anxiety 2000; 7:69-72. [PMID: 9614594] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
It has been suggested that serotonin reuptake inhibitors (SSRIs) may be less effective than tricyclic antidepressants (TCAs) in treatment of melancholic depression. We treated 36 depressed ambulatory patients with doxepin or fluoxetine in a double-blind, randomized 6-week trial with placebo run-in. Seven patients treated with doxepin and 13 patients treated with fluoxetine met diagnostic criteria for melancholic depression. Average daily dose was 169.4 +/- 41.6 mg for doxepin and 36.8 +/- 18 mg for fluoxetine. We observed a 50% response rate in both treatment groups, using as outcome criterion reduction of Hamilton Depression Scale Score to less than 10. Regardless of how strict the definition of response, we found fluoxetine to be as effective as doxepin in our group of melancholic outpatients.
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Affiliation(s)
- P Sandor
- Tourette's Syndrome Clinic, Toronto Hospital, Ontario, Canada
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30
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Irvine J, Newman D. Quality of life issues in the management of patients with ventricular arrhythmias. Can J Cardiol 2000; 16 Suppl C:41C-4C. [PMID: 10887278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Affiliation(s)
- J Irvine
- York University, Toronto General Hospital, Toronto, Canada
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31
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Ritvo P, Robinson G, Irvine J, Brown L, Matthew A, Murphy KJ, Stewart DS, Styra R, Wang C, Mullen M, Cole D, Rosen B. Psychological adjustment to familial genetic risk assessment: differences in two longitudinal samples. Patient Educ Couns 2000; 40:163-172. [PMID: 10771370 DOI: 10.1016/s0738-3991(99)00082-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Heritable cancer risk assessment is an increasingly common method of deriving valuable information relevant to deciding on appropriate screening regimens and preventive treatments. Assessments of heritable risk typically include familial-genetic evaluation, where analyses relate family pedigree to cancer risk, and DNA testing, where analyses indicate genetic mutations associated with cancer risk (e.g., BRCA1/BRCA2 mutations) or their absence. In this paper we report on the psychological responses of women given familial-genetic evaluations for ovarian cancer risk. The baseline and 6 to 12 follow-up assessments of an initial clinic-attending cohort of 65 women are compared with the baseline and 9 to 12 follow-up assessments of a second clinic-attending cohort of 60 women. Sizeable differences were found in the prevalence of clinically significant depression in these two physician or self-referred populations, as assessed by the Center for Epidemiological Studies Depression scale and in the mean scores. Hypotheses accounting for these differences are discussed.
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Affiliation(s)
- P Ritvo
- Research Unit, Division of Preventive Oncology, Cancer Care Ontario, Toronto, Canada
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32
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Wang X, Appukuttan B, Ott S, Patel R, Irvine J, Song J, Park JH, Smith R, Stout JT. Efficient and sustained transgene expression in human corneal cells mediated by a lentiviral vector. Gene Ther 2000; 7:196-200. [PMID: 10694795 DOI: 10.1038/sj.gt.3301075] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The development of vectors and techniques able to transfer potentially therapeutic genetic information to corneal tissues efficiently may have broad clinical applications. Although a variety of vectors have been tested for their ability to transduce corneal tissue, these systems have been ineffective at transducing all cell types or have been associated with a relatively short duration of transgene expression. Towards the implementation of efficient, long-term transgene expression in all corneal cell types, we have studied the ability of a recombinant lentiviral vector, containing the enhanced green fluorescent protein (eGFP), to mediate gene transfer into human corneal tissue in vitro and in situ. Human primary keratocytes, cultured in vitro, were efficiently transduced by a lentiviral vector as determined by fluorescent-activated cell sorting (FACS) and by fluorescent microscopy. Transduction efficiency was found to be dependent upon multiplicity of infection (MOI); 92% of keratocytes were transduced at an MOI of 1000. The proportion of eGFP-positive cells remained unchanged throughout continuous culture for 60 days, indicating stable expression and a lack of selective pressure for or against transduced cells. Human corneal tissue, obtained at the time of penetrating keratoplasty, demonstrated efficient in situ transduction with this vector. Endothelial cells, epithelial cells and stromal keratocytes at the exposed cut edge of the corneal tissue in situ demonstrated eGFP expression. Underlying stromal cells not in direct contact with vector-containing media, were not transduced, implying that virus-cell contact is required for transduction. Transduced corneal tissues expressed eGFP in situ for the life of the corneal button in extended organ culture (60 days). These results imply that lentiviral vectors may prove to be useful tools, able to transduce corneal tissue efficiently, and that transgene expression is temporally stable. Gene Therapy (2000) 7, 196-200.
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Affiliation(s)
- X Wang
- Division of Ophthalmology, Childrens Hospital Los Angeles, University of Southern California, Los Angeles, CA 90027, USA
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Cameron ER, Morton J, Johnston CJ, Irvine J, Bell M, Onions DE, Neil JC, Campbell M, Blyth K. Fas-independent apoptosis in T-cell tumours induced by the CD2-myc transgene. Cell Death Differ 2000; 7:80-8. [PMID: 10713723 DOI: 10.1038/sj.cdd.4400630] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Depending on the cellular context, the Myc oncoprotein is capable of promoting cell proliferation or death by apoptosis. These observations suggest that apoptosis in response to deregulated gene expression may represent a natural brake to tumour development. The pathways by which Myc induces apoptosis are as yet poorly characterised although recent observations on rat fibroblasts over-expressing Myc have demonstrated a requirement for the Fas pathway. To investigate the role of Fas in Myc-induced lymphomagenesis we backcrossed CD2-myc mice onto an lpr background. Rates of tumour development and phenotypic properties, including levels of apoptosis were indistinguishable from CD2-myc controls. Further, tumour cell lines derived from mice expressing a regulatable form of Myc showed inducible apoptosis at similar rates regardless of their lpr genotype. These results show that activation of c-myc and loss of Fas do not collaborate in T lymphoma development and that Myc-induced apoptosis in T-cells occurs by Fas-independent pathways.
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Affiliation(s)
- E R Cameron
- Molecular Oncology Laboratory, Glasgow University Veterinary School, Bearsden Road, Glasgow, G61 1QH, UK.
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Irvine J, Basinski A, Baker B, Jandciu S, Paquette M, Cairns J, Connolly S, Roberts R, Gent M, Dorian P. Depression and risk of sudden cardiac death after acute myocardial infarction: testing for the confounding effects of fatigue. Psychosom Med 1999; 61:729-37. [PMID: 10593621 DOI: 10.1097/00006842-199911000-00001] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.0] [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: 11/25/2022]
Abstract
OBJECTIVES This study examined the impact of depressive symptoms and social support on 2-year sudden cardiac death (SCD) risk, controlling for fatigue symptoms. METHODS Myocardial infarction (MI) patients (N = 671) participating in the Canadian Amiodarone Myocardial Infarction Arrhythmia Trial completed measures of depression, hostility, and social support. RESULTS After controlling for significant biological predictors, psychosocial predictors of increased SCD risk in the survival analysis were greater social network contacts (RR = 1.04; 95% CI = 1.01-1.06; p < .007), lower social participation (RR = 0.98; 95% CI = 0.96-1.00; p < .05), and, in placebo-treated patients, elevated depressive symptoms (RR = 2.45; 95% CI = 1.14-5.35; p < .02). Fatigue was associated with SCD (RR = 1.31; 95% CI = 1.11-1.53; p < .001), and, when included in the model, diminished the influence of depression (RR = 1.73; 95% CI = 0.75-3.98; p = .20). When the cognitive-affective depressive symptoms were examined separately from somatic symptoms, there was a trend for an association between cognitive-affective symptoms and SCD in placebo-treated patients after controlling for fatigue (RR = 1.09; 95% CI = 0.99-1.19, p < .06). CONCLUSIONS Symptoms of depression and fatigue overlap in patients with MI. The trend for the cognitive-affective symptoms of depression to be associated with SCD risk, even after controlling for dyspnea/fatigue, suggests that the association between depression and mortality after AMI cannot be entirely explained as a confound of cardiac-related fatigue. The independent contribution of social participation suggests a role of both depressive symptomatology and social factors in influencing mortality risk after MI.
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Affiliation(s)
- J Irvine
- Toronto General Hospital, University Health Network, Department of Psychiatry, University of Toronto, Ontario, Canada.
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Abstract
The motivations of cancer patients in seeking complementary therapies are, fundamentally, self-healing motivations which, when engaged appropriately, can contribute to the patient's psychological and physical well being. In this paper, we apply a theoretical model, the Risk Adaptation Model, to furthering the clinical understanding of the motivations of cancer patients in seeking complementary therapies. The model identifies six discrete cognitive processes which, in combination, are hypothesized to play a central role in therapy seeking. Emphasis in this model is placed on the patient's need to maintain positive expectancies (optimism) when faced with the risk and uncertainty of cancer. This understanding of complementary-therapy seeking is grounded in the perspective that clinicians must respect the autonomy of cancer patients in their quest for appropriate therapies, and assist rather than direct their process of therapy-seeking.
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Affiliation(s)
- P Ritvo
- Division of Preventive Oncology, Cancer Care Ontario, Toronto, Ontario, Canada
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Ritvo P, Robinson G, Irvine J, Brown L, Murphy KJ, Stewart DS, Styra R, Wang C, Mullen M, Cole D, Rosen B. A longitudinal study of psychological adjustment to familial genetic risk assessment for ovarian cancer. Gynecol Oncol 1999; 74:331-7. [PMID: 10479489 DOI: 10.1006/gyno.1999.5518] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
OBJECTIVES To evaluate the psychological adjustment of women during initial genetic ovarian cancer risk assessment and at clinic follow-up, 6-12 months later. METHODS Sixty-five subjects were assessed with the Centre for Epidemiological Studies Depression Scale (CESD), Spielberger's State Anxiety Inventory, and an 18-item, investigator-designed questionnaire yielding self-report on screening responses, worry about increased risk, identification of cancer-related deaths in relatives, worry about future cancer risks of daughters, alteration of future plans as a result of ovarian cancer risk, etc. RESULTS Thirty-three percent of subjects had CESD scores above the established cutoff for depression at baseline and 38% had scores above cutoff at follow-up. Sixteen percent of subjects had state scores on the State-Trait Anxiety Inventory higher than 1 standard deviation above average (norm) at baseline, while only 6% had scores higher than 1 SD above average at follow-up. CONCLUSION To identify factors associated with self-reported depression at follow-up, a series of demographic and self-reported variables (e.g., presence of identified problems in family, impact of genetic risk information, concern for daughter in the future) were entered in a multiple regression analysis with the CESD follow-up score as the dependent variable. Only one predictor accounted for a significant amount of variance in depression scores. Concern for daughter's risk in the future was associated with higher depression scores at follow-up (R = 0.33, P<0.02, R(2) = 11%).
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Affiliation(s)
- P Ritvo
- Department of Public Health Sciences, Family & Community Medicine and Psychiatry, University of Toronto, Ontario, Canada.
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Irvine J, Baker B, Smith J, Jandciu S, Paquette M, Cairns J, Connolly S, Roberts R, Gent M, Dorian P. Poor adherence to placebo or amiodarone therapy predicts mortality: results from the CAMIAT study. Canadian Amiodarone Myocardial Infarction Arrhythmia Trial. Psychosom Med 1999; 61:566-75. [PMID: 10443767 DOI: 10.1097/00006842-199907000-00023] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
OBJECTIVE This study examined the relationship between adherence, mortality, and psychosocial factors. METHODS Subjects were 1141 patients participating in the Canadian Amiodarone Myocardial Infarction Arrhythmia Trial. Poor adherence to study medication (amiodarone or placebo), measured by pill count over 2 years, was defined as the lower 20th percentile of the pill count distribution. Predictors of adherence were also studied and included demographic and cardiac variables and, in a subset of participants (N = 671), measures of depression, distress, hostility, and social support. RESULTS In survival analysis controlling for cardiac and demographic variables, poor adherence in the placebo and amiodarone groups was associated with an increased risk of sudden cardiac death (relative risk (RR) = 2.11, 95% confidence interval (CI) = 1.03-4.56, p < .05; and RR = 3.15, 95% CI = 1.34-7.44, p < .01, respectively), total cardiac mortality (RR = 2.04, 95% CI = 1.12-3.72, p < .02; and RR = 2.49, 95% CI = 1.32-4.72, p < .01, respectively), and all-cause mortality (RR = 2.25, 95% CI = 1.27-3.97, p < .001; and RR = 2.34, 95% CI = 1.32-4.17, p < .004, respectively). Logistic regression analysis identified two predictors of poor adherence to placebo: age > 70 years (odds ratio = 2.18, 95% CI = 1.11-4.29, p < .03) and social activities in the month before the index heart attack (odds ratio = 1.02, 95% CI = 1.00-1.04, p < .05). CONCLUSIONS Poor adherence is associated with a greater risk of mortality. The relationship between adherence and social activities suggests a higher motivation to adhere to treatment in individuals more engaged in enjoyable activities.
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Affiliation(s)
- J Irvine
- The Toronto Hospital, Department of Psychiatry, University of Toronto, Ontario, Canada.
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Arthur HM, Garfinkel PE, Irvine J. Development and testing of a new hostility scale. Can J Cardiol 1999; 15:539-44. [PMID: 10350663] [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: 02/12/2023] Open
Abstract
Evidence suggests that assessment of global type A behaviour as a coronary risk factor may not be the most fruitful strategy because some components, particularly hostility, may be more harmful than others. Measurement of hostility has been primarily through two types of instrumentation: the Type A Structured Interview (SI) and the Cook-Medley (Ho) scale. Deficiencies in the measurement of hostility have resulted from a lack of conceptual clarity because definitions of hostility have been blurred by overlap with the concepts of anger and aggression. The main objective of this study was to develop and test an instrument that focuses hostility on attitude rather than emotion or behaviour. Psychometric properties of the Hostile Attitude Scale (HAS) were Cronbach's alpha, 0.80, and correlation of 0.56 with the Ho scale and 0.43 with the SI. In a clinical investigation that used the HAS, SI and Ho scale, all measures were significantly correlated with angiogram outcome, although the strongest relationship was with the HAS. Hostile attitude alone (HAS) accounted for 6% of explained variance in angiogram outcome based on regression analysis. The HAS is offered as a short, easily administered measure of hostility, with particular emphasis on cognitive aspects of the construct.
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Abstract
Living in the high Arctic, the Svalbard reindeer (Rangifer tarandus platyrhynchus) and its trichostrongyle nematodes experience a long cold winter from October to late May/early June. Over this period, transmission would be expected to be low. However, in culled reindeer the abundance of infection increased from autumn to late winter, providing evidence for continued transmission within this period. To our knowledge this is the first time this has been demonstrated in a climate with temperatures consistently below 0 degrees C. In one winter (1996-1997), the average fraction of nematodes found as larvae in the abomasal mucosa increased from around 10% to 50% between October and March. This suggests that arrested development took place throughout the winter. We found no evidence for an efficient acquired immune response towards the nematodes. The abundance of infection did not tend to decrease with increasing host age after an earlier peak, but levelled off instead, as predicted by a simple immigration-death model. In the late winter when the nutritional plane is low, both adult reindeer and calves had high worm burdens at intensities that may affect their condition and fitness.
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Affiliation(s)
- O Halvorsen
- Zoological Museum, University of Oslo, Norway.
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Scott I, Dick A, Irvine J, Stear MJ, McKellar QA. The distribution of pepsinogen within the abomasa of cattle and sheep infected with Ostertagia spp. and sheep infected with Haemonchus contortus. Vet Parasitol 1999; 82:145-59. [PMID: 10321586 DOI: 10.1016/s0304-4017(99)00006-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The effect of nematode infections on the production of pepsinogen by ruminants was investigated immunohistochemically and biochemically. Abomasal tissues were collected from parasite-naive cattle and sheep, from sheep infected with predominantly Ostertagia circumcincta, sheep infected experimentally with Haemonchus contortus and cattle infected with Ostertagia ostertagi. Pepsinogen was also assayed biochemically in homogenates of fundic mucosae from sheep infected with predominantly O. circumcincta. Infection with Ostertagia spp. parasites was associated mainly with nodular hyperplasia, resulting in increased numbers of cells that produce both pepsinogen and mucus. Measured biochemically, nodules contained more pepsinogen than adjacent more normal mucosa (p < 0.05), and this effect was largely attributable to the greater mass of nodules. Infection of sheep with H. contortus was associated with generalised hyperplasia, characterised by increased numbers of mucopeptic cells and in at least one animal with reductions in parietal cell numbers. At the same time, the zymogen granule content of chief cells was reduced. Similar changes were occasionally seen in sheep infected predominantly with O. circumcincta. Generalised hyperplasia is likely to be indicative of the presence of ambulatory parasitic stages as opposed to those confined to nodules. The potential for the enhanced production of pepsinogen by increased numbers of cells with a joint mucous cell and zymogenic cell phenotype may offset decreases in the numbers of chief cells or reductions in chief cell activity.
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Affiliation(s)
- I Scott
- Department of Veterinary Pharmacology, University of Glasgow Veterinary School, Scotland, UK.
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Fodor G, Cutler H, Irvine J, Ramsden V, Tremblay G, Chockalingam A. Adherence to non-pharmacologic therapy for hypertension: problems and solutions. Can J Public Health 1999. [PMID: 9813920 DOI: 10.1007/bf03404493] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The efficacy of a number of non-pharmacologic interventions in the therapy of primary hypertension has been firmly established. Most prominently, weight reduction, sodium restriction, and alcohol restriction have significant effects on lowering blood pressure. Increased physical activity contributes to management of hypertensive patients in a variety of ways: apart from having a direct impact on blood pressure level, it is an important supportive factor in a weight-reducing regime. The success in applying these non-pharmacologic measures in standard patient population is rather limited. A salient example is the lack of success in weight reduction. Reduction of sodium in the diet is somewhat more successful, however, the problem is that most of the salt intake is non-discretionary. Adherence to physical activity regimes is in the range of what has been observed in pharmacologic therapy. Research and experience in the past few years are providing a better understanding of the factors determining compliance with prescribed therapeutical regimes. Further research is needed to develop innovative strategies for providing efficacious non-pharmacologic measures to hypertensive patients.
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Affiliation(s)
- G Fodor
- University of Ottawa Heart Institute Prevention and Rehabilitation Centre, ON.
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Abstract
In order to investigate the role that the human T-lymphotropic virus type I (HTLV-I) tax oncogene plays in apoptosis and transformation in vivo, four lines of HTLV-I tax transgenic mice were generated under the regulatory control of the CD3-epsilon promoter-enhancer sequence. These mice develop a variety of phenotypes including mesenchymal tumours, which develop at wound sites, and salivary and mammary adenomas. In situ DNA fragment labelling and immunocytochemical analysis of these tumours reveals that they display enhanced levels of apoptosis, which is associated with elevated levels of Myc, Fos, Jun, and p53 protein expression. Furthermore, double immunofluorescent staining shows that Tax expression and apoptosis co-localize, indicating that Tax expression is closely associated with apoptosis in vivo.
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Affiliation(s)
- A P Hall
- Department of Veterinary Pathology, Glasgow University Veterinary School, U.K
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Chockalingam A, Bacher M, Campbell N, Cutler H, Drover A, Feldman R, Fodor G, Irvine J, Ramsden V, Thivierge R, Tremblay G. Adherence to management of high blood pressure: recommendations of the Canadian Coalition for High Blood Pressure Prevention and Control. Can J Public Health 1998; 89:I5-11. [PMID: 9813919 PMCID: PMC6990294] [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] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
Abstract
Adherence or compliance, in the context of medical treatment, refers to how well a patient follows and sticks to the management plan developed with her/his health care provider, which may include pharmacologic agents as well as changes in lifestyle. Adherence is of great concern in asymptomatic conditions such as hypertension, where lack of control may have serious ramifications including end organ damage and premature mortality. To address this issue, the Canadian Coalition for High Blood Pressure Prevention and Control established a national Advisory Committee on Adherence to the Management of High Blood Pressure. The Advisory Committee consisted of 11 members from different disciplines of health care providers. The Committee reviewed all evidences to date and drew up four practical recommendations with respect to patient, provider and environment. Based on Canadian Task Force on Periodic Health Examination's guidelines, all four recommendations can be classified as 'level C' with a quality of evidence of II.
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Affiliation(s)
- A Chockalingam
- Adult Health Division, HPPB, Health Canada, Ottawa, Ontario.
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Irvine J, Perks MP, Magnani F, Grace J. The response of Pinus sylvestris to drought: stomatal control of transpiration and hydraulic conductance. Tree Physiol 1998; 18:393-402. [PMID: 12651364 DOI: 10.1093/treephys/18.6.393] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
We investigated the impact of drought on the physiology of 41-year-old Scots pine (Pinus sylvestris L.) in central Scotland. Measurements were made of the seasonal course of transpiration, canopy stomatal conductance, needle water potential, xylem water content, soil-to-needle hydraulic resistance, and growth. Comparison was made between drought-treated plots and those receiving average precipitation. In response to drought, transpiration rate declined once volumetric water content (VWC) over the top 20 cm of soil reached a threshold value of 12%. Thereafter, transpiration was a near linear function of soil water content. As the soil water deficit developed, the hydraulic resistance between soil and needles increased by a factor of three as predawn needle water potential declined from -0.54 to -0.71 MPa. A small but significant increase in xylem embolism was detected in 1-year-old shoots. Stomatal control of transpiration prevented needle water potential from declining below -1.5 MPa. Basal area, and shoot and needle growth were significantly reduced in the drought treatment. In the year following the drought, canopy stomatal conductance and soil-to-needle hydraulic resistance recovered. Current-year needle extension recovered, but a significant reduction in basal area increment was evident one year after the drought. The results suggest that, in response to soil water deficit, mature Scots pine closes its stomata sufficiently to prevent the development of substantial xylem embolism. Reduced growth in the year after a severe soil water deficit is most likely to be the result of reduced assimilation in the year of the drought, rather than to any residual embolism carried over from one year to the next.
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Affiliation(s)
- J. Irvine
- Institute of Ecology and Resource Management, University of Edinburgh, Darwin Building, Mayfield Road, Edinburgh EH9 3JU, U.K
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Scott I, Stear MJ, Irvine J, Dick A, Wallace DS, McKellar QA. Changes in the zymogenic cell populations of the abomasa of sheep infected with Haemonchus contortus. Parasitology 1998; 116 ( Pt 6):569-77. [PMID: 9651940 DOI: 10.1017/s0031182098002704] [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: 02/08/2023]
Abstract
The effects of dietary urea supplementation and of a 10-week trickle infection regime, simulating chronic exposure to Haemonchus contortus, on the zymogenic population of the abomasa of Hampshire Down lambs was examined. At necropsy a variety of parameters including plasma pepsinogen concentration, the wet weights of abomasal fundic mucosal pieces and the amounts of pepsinogen contained in them, were assessed. Tissue pepsinogen concentration was measured as the total, acid-stable proteolytic activity present in mucosal homogenates, as well as immunohistochemically. The immunohistochemical findings were quantified using computer-aided image analysis. Elevation of plasma pepsinogen concentrations in infected animals was of borderline significance (P = 0.06). The fundic mucosae of infected animals were heavier (P < 0.02) than those of control animals, but there was no overall change in the pepsinogen content of tissues. Immunohistochemistry revealed that infected animals had increased numbers of zymogenic cells, due to mucous cell hyperplasia and the adaptation of cells to produce both mucins and pepsinogen. The pepsinogen content of chief cells, the major source of pepsinogen in uninfected animals, was reduced in infected lambs. Image analysis confirmed that at a mid-point of the mucosa of infected animals there was increased pepsinogen-specific immunoreactivity that corresponded with areas of mucosal hyperplasia. Mucous cell hyperplasia might therefore allow the maintenance of pepsinogen secretion in infected animals even if chief cell output is reduced.
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Affiliation(s)
- I Scott
- Department of Veterinary Pharmacology, University of Glasgow Veterinary School, Bearsden.
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Shnek ZM, Foley FW, LaRocca NG, Gordon WA, DeLuca J, Schwartzman HG, Halper J, Lennox S, Irvine J. Helplessness, self-efficacy, cognitive distortions, and depression in multiple sclerosis and spinal cord injury. Ann Behav Med 1998; 19:287-94. [PMID: 9603703 DOI: 10.1007/bf02892293] [Citation(s) in RCA: 99] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The aim of this study was to determine if learned helplessness, self-efficacy, and cognitive distortions would predict depression in a sample of 80 individuals with multiple sclerosis (MS) and 80 individuals with a spinal cord injury (SCI). As MS and SCI usually present with disparate disease courses and etiologies, a secondary objective was to determine if individuals with MS would exhibit greater levels of helplessness, cognitive distortions, and depression and lower levels of self-efficacy than those with SCI. Results indicated that helplessness and self-efficacy significantly predicted depression for both the MS and SCI groups after controlling for confounding variables. Cognitive distortions had no independent effect, indicating that cognitive distortions may have caused feelings of helplessness and low self-efficacy and, in this way, had indirect effects on depression. The MS group exhibited significantly greater levels of depression and helplessness and significantly lower levels of self-efficacy than the SCI group. It was hypothesized that it may have been the combination of an unpredictable course of disease activity and the possibility of being affected by MS in many different ways that produced greater feelings of depression, helplessness, and low self-efficacy in the MS group.
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Affiliation(s)
- Z M Shnek
- Rehabilitation Institute of Toronto, Canada
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Khaykin Y, Dorian P, Baker B, Shapiro C, Sandor P, Mironov D, Irvine J, Newman D. Autonomic correlates of antidepressant treatment using heart-rate variability analysis. Can J Psychiatry 1998; 43:183-6. [PMID: 9533973 DOI: 10.1177/070674379804300209] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE To assess the 24-hour temporal-domain heart-rate variability correlates of treatment with fluoxetine or doxepin for depression. METHOD A randomized evaluation of fluoxetine and doxepin measured a 50% change in the Hamilton Depression Rating Scale (HDRS) score as a response to therapy and was correlated with measures of standard deviation of the mean of all 5-minute segments of normal electrocardiographic R-R intervals (SDANN), standard deviation of all normal R-R intervals (SDNN), root mean square of successive differences in R-R intervals (r-MSSD), and percentage difference between adjacent normal R-R intervals that are greater than 50 msec (pNN50) from 24-hour electrocardiogram (ECG) tapes. RESULTS Ten out of 14 patients responded. Response was associated with an increase in SDANN of 17% (P < 0.05). Nonresponse was associated with a 17% decrease in SDANN and a 22% decrease in SDNN (both P < 0.05). No other measures correlated with therapeutic response. No heart-rate variability (HRV) differences between the 2 drug therapies were observed. CONCLUSION Twenty-four-hour HRV measures may be useful in assessing response to antidepressant therapy.
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Affiliation(s)
- Y Khaykin
- Division of Cardiology, St Michael's Hospital, University of Toronto, Ontario
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Abstract
A regression-based model was developed relating aerial image quality, expressed in terms of the National Imagery Interpretability Rating Scale (NIIRS), to fundamental image attributes. The General Image-Quality Equation (GIQE) treats three main attributes: scale, expressed as the ground-sampled distance; sharpness, measured from the system modulation transfer function; and the signal-to-noise ratio. The GIQE can be applied to any visible sensor and predicts NIIRS ratings with a standard error of 0.3 NIIRS. The image attributes treated by the GIQE are influenced by system design and operation parameters. The GIQE allows system designers and operators to perform trade-offs for the optimization of image quality.
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Rosen B, Irvine J, Ritvo P, Shapiro H, Stewart D, Reynolds K, Robinson G, Thomas J, Neuman J, Murphy J. The feasibility of assessing women's perceptions of the risks and benefits of fertility drug therapy in relation to ovarian cancer risk. Fertil Steril 1997; 68:90-4. [PMID: 9207590 DOI: 10.1016/s0015-0282(97)81481-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE To determine the feasibility of asking women undergoing fertility treatment the maximum increased risk of ovarian cancer they would be willing to tolerate in order to take ovulation-induction drugs. DESIGN A prospective pilot study of women attending fertility clinics over a 2-month period. SETTING Two tertiary care fertility clinics in Toronto. PATIENT(S) Sixty-one English-speaking women were approached and 85% (n = 52) were enrolled. INTERVENTION(S) A self-administered questionnaire with fertility-specific questions. Thirty-eight women also were asked to complete standardized scales of anxiety and optimism. MAIN OUTCOME MEASURE(S) Women's report of the maximum level of lifetime risk of ovarian cancer they were willing to tolerate in order to undergo fertility treatment. RESULT(S) Seventy-nine percent were willing to accept an increased risk of ovarian cancer. Only 24% understood that treatment for ovarian cancer usually was not curative. CONCLUSION(S) A majority of patients were willing to tolerate a modest increase in their lifetime risk of ovarian cancer because of fertility treatment, most basing their estimate of acceptable risk on limited awareness of the issue.
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Affiliation(s)
- B Rosen
- Toronto Hospital, University of Toronto, Ontario, Canada.
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Deber RB, Kraetschmer N, Irvine J. What role do patients wish to play in treatment decision making? Arch Intern Med 1996; 156:1414-1420. [PMID: 8678709] [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] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
BACKGROUND Although current ideology suggests patients should be active participants in decision making about their care, the literature suggests that patients wish to be informed but not involved. OBJECTIVE To test the hypothesis that most patients want their physicians to take the responsibility for problem solving (PS, identifying the one right answer), but that many want to be involved in decision-making (DM, selecting the most desired bundle of outcomes) tasks. METHODS Survey responses from 300 patients undergoing angiogram at a Toronto, Ontario, hospital were analyzed (response rate, 72%). Survey items included scales to measure desire for information and participation, including Autonomy Preference Index, the Krantz Health Opinion Survey, and the Deber-Kraetschmer Problem-Solving Decision-Making Scale measured on a scale from, 1 (doctor only) to 5 (patient only). RESULTS Patients had a relatively high desire for information. On the Problem-Solving Decision-Making Scale, they overwhelmingly wished the PS tasks to be performed by or shared with the physician (98.4% of the 12 PS scores are between 1 and 3), but wanted to be involved in DM (78% of the 6 DM scores are between 3 and 5). Preference for handing over control to the physician was significantly greater for the vignette involving potential mortality (chest pain) than for the vignettes involving mainly morbidity (urinary problems) or quality of life (fertility). CONCLUSIONS Although patients do not wish to be involved in PS tasks, few wish to hand over DM control to their physician. These findings suggest 2 major roles for clinicians--assisting patients in PS to structure choices and supporting them in making often difficult decisions.
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Affiliation(s)
- R B Deber
- Department of Health Administration, University of Toronto, Ontario
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