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Fortuna KL, DiMilia PR, Lohman MC, Bruce ML, Zubritsky CD, Halaby MR, Walker RM, Brooks JM, Bartels SJ. Feasibility, Acceptability, and Preliminary Effectiveness of a Peer-Delivered and Technology Supported Self-Management Intervention for Older Adults with Serious Mental Illness. Psychiatr Q 2018; 89:293-305. [PMID: 28948424 PMCID: PMC5874159 DOI: 10.1007/s11126-017-9534-7] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
To assess the feasibility, acceptability, and preliminary effectiveness of a peer-delivered and technology supported integrated medical and psychiatric self-management intervention for older adults with serious mental illness. Ten older adults with serious mental illness (i.e., schizophrenia, schizoaffective disorder, bipolar disorder, or major depressive disorder) and medical comorbidity (i.e., cardiovascular disease, obesity, diabetes, chronic obstructive pulmonary disease, hypertension, and/or high cholesterol) aged 60 years and older received the PeerTECH intervention in their homes. Three certified peer specialists were trained to deliver PeerTECH. Data were collected at baseline, one-month, and three-month. The pilot study demonstrated that a three-month, peer-delivered and technology-supported integrated medical and psychiatric self-management intervention ("PeerTECH") was experienced by peer specialists and participants as feasible and acceptable. PeerTECH was associated with statistically significant improvements in psychiatric self-management. In addition, pre/post, non-statistically significant improvements were observed in self-efficacy for managing chronic health conditions, hope, quality of life, medical self-management skills, and empowerment. This pre/post pilot study demonstrated it is possible to train peers to use technology to deliver an integrated psychiatric and medical self-management intervention in a home-based setting to older adults with serious mental illness with fidelity. These findings provide preliminary evidence that a peer-delivered and technology-supported intervention designed to improve medical and psychiatric self-management is feasible, acceptable, and is potentially associated with improvements in psychiatric self-management, self-efficacy for managing chronic health conditions, hope, quality of life, medical self-management skills, and empowerment with older adults with serious mental illness and chronic health conditions.
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Affiliation(s)
- Karen L Fortuna
- Dartmouth Centers for Health and Aging, 46 Centerra Parkway, Suite 200, Lebanon, NH, 03766, USA.
- CDC Health Promotion Research Center at Dartmouth, Lebanon, NH, USA.
- Department of Psychiatry, Geisel School of Medicine at Dartmouth, Hanover, NH, USA.
| | - Peter R DiMilia
- Dartmouth Centers for Health and Aging, 46 Centerra Parkway, Suite 200, Lebanon, NH, 03766, USA
- The Dartmouth Institute for Health Policy & Clinical Practice, Lebanon, NH, USA
| | - Matthew C Lohman
- Dartmouth Centers for Health and Aging, 46 Centerra Parkway, Suite 200, Lebanon, NH, 03766, USA
- CDC Health Promotion Research Center at Dartmouth, Lebanon, NH, USA
- Department of Psychiatry, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - Martha L Bruce
- Department of Psychiatry, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
- The Dartmouth Institute for Health Policy & Clinical Practice, Lebanon, NH, USA
| | - Cynthia D Zubritsky
- Center for Mental Health Policy and Services Research, School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | | | | | - Jessica M Brooks
- Dartmouth Centers for Health and Aging, 46 Centerra Parkway, Suite 200, Lebanon, NH, 03766, USA
- Department of Psychiatry, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - Stephen J Bartels
- Dartmouth Centers for Health and Aging, 46 Centerra Parkway, Suite 200, Lebanon, NH, 03766, USA
- CDC Health Promotion Research Center at Dartmouth, Lebanon, NH, USA
- Department of Psychiatry, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
- The Dartmouth Institute for Health Policy & Clinical Practice, Lebanon, NH, USA
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Wu X, Deutschbauer AM, Kazakov AE, Wetmore KM, Cwick BA, Walker RM, Novichkov PS, Arkin AP, Chakraborty R. Draft Genome Sequences of Two Janthinobacteriumlividum Strains, Isolated from Pristine Groundwater Collected from the Oak Ridge Field Research Center. Genome Announc 2017; 5:e00582-17. [PMID: 28663297 PMCID: PMC5638281 DOI: 10.1128/genomea.00582-17] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 05/15/2017] [Indexed: 11/20/2022]
Abstract
We present here the draft genome sequences of two Janthinobacterium lividum strains, GW456P and GW458P, isolated from groundwater samples collected from a background site at the Oak Ridge Field Research Center. Production of a purple pigment by these two strains was observed when grown on diluted (1/10) LB agar plates.
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Affiliation(s)
- Xiaoqin Wu
- Earth and Environmental Sciences, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Adam M Deutschbauer
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Alexey E Kazakov
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Kelly M Wetmore
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
- Program in Comparative Biochemistry, University of California, Berkeley, California, USA
| | - Bryson A Cwick
- Earth and Environmental Sciences, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Robert M Walker
- Earth and Environmental Sciences, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Pavel S Novichkov
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Adam P Arkin
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
- Department of Bioengineering, University of California, Berkeley, California, USA
| | - Romy Chakraborty
- Earth and Environmental Sciences, Lawrence Berkeley National Laboratory, Berkeley, California, USA
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Abstract
Elderly subjects (N = 166) of varying socioeconomic backgrounds from two sites were given identical resuscitation information and were studied to determine the relationship between socioeconomic status and resuscitation preferences. Resuscitation preferences varied among the four hypothetical scenarios. Univariate analyses revealed that those who were older, male, non-Caucasian, less educated, and had less income desired more cardiopulmonary resuscitation (CPR) in the scenarios. Multivanate analysis limited significant variables to age, gender, race, and level of education. Thus there appears to be a strong relationship between socioeconomic status and desire for CPR. Future research should evaluate whether the sociodemographic variables represent proxy variables for underlying life values that may influence resuscitation preferences. Implications for CPR decision making and health policy are discussed.
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Affiliation(s)
| | - Robert M. Walker
- University of South Florida College of Medicine James
A. Haley Veteran's Hospital
| | - David R. Kramer
- University of South Florida College of Medicine James
A. Haley Veteran's Hospital
| | - Bruce E. Robinson
- University of South Florida College of Medicine James
A. Haley Veteran's Hospital
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Walker RM. Team response to internal disagreement about professional conduct. Virtual Mentor 2013; 15:493-497. [PMID: 23759154 DOI: 10.1001/virtualmentor.2013.15.6.ecas1-1306] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Affiliation(s)
- Robert M Walker
- Division of Ethics, Humanities, and Palliative Medicine at the University of South Florida Health Morsani College of Medicine in Tampa, Tampa, FL, USA
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Gopalakrishnan GS, Gardner DS, Dandrea J, Langley-Evans SC, Pearce S, Kurlak LO, Walker RM, Seetho IW, Keisler DH, Ramsay MM, Stephenson T, Symonds ME. Influence of maternal pre-pregnancy body composition and diet during early-mid pregnancy on cardiovascular function and nephron number in juvenile sheep. Br J Nutr 2006; 94:938-47. [PMID: 16351771 PMCID: PMC2656281 DOI: 10.1079/bjn20051559] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The prenatal diet can program an individual's cardiovascular system towards later higher resting blood pressure and kidney dysfunction, but the extent to which these programmed responses are directly determined by the timing of maternal nutritional manipulation is unknown. In the present study we examined whether maternal nutrient restriction targeted over the period of maximal placental growth, i.e. days 28-80 of gestation, resulted in altered blood pressure or kidney development in the juvenile offspring. This was undertaken in 6-month-old sheep born to mothers fed control (100-150 % of the recommended metabolisable energy (ME) intake for that stage of gestation) or nutrient-restricted (NR; 50 % ME; n 6) diets between days 28 and 80 of gestation. Controls were additionally grouped according to normal (>3, n 7) or low body condition score (LBCS; <2, n 6), thereby enabling us to examine the effect of maternal body composition on later cardiovascular function. From day 80 to term (approximately 147 d) all sheep were fed to 100 % ME. Offspring were weaned at 12 weeks and pasture-reared until 6 months of age when cardiovascular function was determined. Both LBCS and NR sheep tended to have lower resting systolic (control, 85 (se 2); LBCS, 77 (se 3); NR, 77 (se 3) mmHg) and diastolic blood pressure relative to controls. Total nephron count was markedly lower in both LBCS and NR relative to controls (LBCS, 59 (se 6); NR, 56 (se 12) %). Our data suggest that maternal body composition around conception is as important as the level of nutrient intake during early pregnancy in programming later cardiovascular health.
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Affiliation(s)
- G S Gopalakrishnan
- Centre for Reproduction and Early Life, Institute of Clinical Research, University Hospital, Nottingham NG7 2UH, UK
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Walker RM. Symposium on safe surgery. The metabolic response to operation and injury. The morbidity and mortality of surgical operations. Br J Surg 2005; 54:Suppl:428-31. [PMID: 6024923 DOI: 10.1002/bjs.1800541308] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Abstract
General anaesthesia in 12 pregnant ewes undergoing surgery for fetal physiological research was supplemented with an intravenous infusion of remifentanil. This allowed us to employ a lighter plane of surgical anaesthesia and to use intermittent positive pressure ventilation. Our aim was to improve fetomaternal outcome. We monitored maternal pulse, blood pressure, transcutaneous oxygen saturation and end-tidal carbon dioxide levels. Remifentanil doses of 0.75-2.0 microg/kg/min were needed and typically this allowed halothane concentrations of 1-1.5% to be used for maintenance of anaesthesia. Surgery lasted up to 2.5 h. All 12 ewes and their singleton fetuses survived the peri- and postoperative period in good condition.
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Affiliation(s)
- V L Webster
- University Department of Anaesthesia, Queen's Medical Centre, University Hospital, Nottingham, UK
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Gopalakrishnan GS, Gardner DS, Rhind SM, Rae MT, Kyle CE, Brooks AN, Walker RM, Ramsay MM, Keisler DH, Stephenson T, Symonds ME. Programming of adult cardiovascular function after early maternal undernutrition in sheep. Am J Physiol Regul Integr Comp Physiol 2004; 287:R12-20. [PMID: 14975924 DOI: 10.1152/ajpregu.00687.2003] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The prenatal nutritional environment influences the subsequent risk of hypertension in adulthood. Animal studies have used, generally, the rat as a model species to illustrate the association between maternal nutrient intake and blood pressure in the resulting adult offspring. No study to date has shown programming of adult cardiovascular function in the sheep through maternal dietary intervention. We therefore fed pregnant sheep to either 100% recommended intake from day 0 of gestation to term [ approximately 147 days gestational age (dGA); controls n = 8] or to 50% recommended intake from day 0 to 95 dGA and thereafter to 100% intake (NR; n = 9). Sheep lambed naturally, offspring were weaned at 16 wk, and the male offspring were reared on pasture until 3 yr of age. At this time, cardiovascular catheters were inserted under halothane anesthesia and sheep were allowed 2-4 days recovery. Basal cardiovascular status and pressor responses to infusion of norepinephrine, angiotensin II, and captopril were then assessed alongside basal plasma concentrations of glucose, cortisol, and leptin. NR sheep were of similar birth weight to controls but at 3 yr of age had higher blood pressure before, but not after, feeding. Peripheral sensitivity to vasoconstrictor infusion was similar between dietary groups, although a reflex bradycardia was not apparent in NR sheep during norepinephrine infusion. Circulating leptin correlated well with fat mass and increased more after vasoconstrictor infusion in NR sheep. In conclusion, early NR has been shown to program aspects of cardiovascular control and adipocyte function in adult sheep.
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Affiliation(s)
- G S Gopalakrishnan
- Academic Division of Child Health, School of Human Development, Univ. Hospital, Nottingham NG7 2UH, UK
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Hunter MG, Hudson N, Mitchell M, Walker RM, Webb R. Resumption of follicle growth in gilts after ovarian autografting. Anim Reprod Sci 2004; 80:317-28. [PMID: 15036507 DOI: 10.1016/s0378-4320(03)00159-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2002] [Revised: 05/23/2003] [Accepted: 06/20/2003] [Indexed: 11/18/2022]
Abstract
The aims of the study were to evaluate autografting of porcine ovarian tissue in terms of establishment of a blood supply, follicle survival and development, commencement of oestrous cycles and endocrine patterns in this polyovular species. Experiment 1, a preliminary study on four gilts, showed that ovarian tissue slices survived the grafting procedure and re-vascularised. In Experiment 2, a further six pre-pubertal gilts had both ovaries surgically removed and two thin cortical slices of each ovary were immediately reattached to each of the ovarian pedicles. Blood samples were taken at surgery and then weekly. Two gilts were slaughtered 2 weeks after surgery and ovarian tissue recovered. The remaining four gilts underwent daily checks for behavioural oestrus until slaughter 24 weeks after surgery. All four gilts showed standing heat at least once prior to slaughter. Plasma LH and FSH concentrations increased significantly (P<0.01) by 3 days after surgery, then fell gradually, but did not return to pre-surgery levels. Progesterone concentrations showed some evidence of cyclicity in all animals. In the grafted tissue, re-vascularisation of the tissue was apparent by 2 weeks post-grafting, although no preantral or antral follicles were observed. The tissue recovered after 24 weeks contained healthy preantral and antral follicles, luteal tissue and some large cystic follicles. It is unclear whether these cysts were the result of ovarian or hypothalamic/pituitary disturbance. In conclusion, the results of this study have shown that follicle growth and resumption of cyclicity can be achieved following ovarian autografting in pigs and indicate that this will be a useful model for investigating the mechanisms that control the early stages of follicular growth and ultimately ovulation rate in this multiovular species.
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Affiliation(s)
- M G Hunter
- School of Biosciences, University of Nottingham, Sutton Bonington, Leics LE12 5RD, UK.
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Abstract
Laboratory testing for drugs of abuse is often conducted in medical settings, with little consideration of the technical limitations and the potential for legal and social harm to the patient. We consider several technical problems associated with such testing, including the lack of chain-of-custody procedures, the possibility of false-positive results with screening immunoassays, and the infrequency of confirmatory testing. Important ethical issues arise because of the sensitive nature of drug test results, the ramifications of false-positive results, the limitations of confidentiality protection, and the practice of testing without the patient's knowledge. Taken together, these technical and ethical concerns suggest that drug testing policies in medical settings should specify which conditions require explicit informed consent, as well as create procedures for protecting this sensitive information.
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Affiliation(s)
- Elizabeth A Warner
- Department of Internal Medicine, Division of General Internal Medicine, University of South Florida, Tampa, Florida 33612, USA.
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Abstract
We have identified six circumstellar silicate grains within interplanetary dust particles (IDPs). Their extrasolar origins are demonstrated by their extremely anomalous oxygen isotopic compositions. Three 17O-rich grains appear to originate from red giant or asymptotic giant branch stars. One 16O-rich grain may be from a metal-poor star. Two 16O-poor grains have unknown stellar sources. One of the grains is forsterite, and two are amorphous silicate "GEMS" (glass with embedded metal and sulfides), which is consistent with astronomical identifications of crystalline and amorphous silicates in the outflows of evolved stars. These observations suggest cometary origins of these IDPs and underscore the perplexing absence of silicates among circumstellar dust grains from meteorites.
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Affiliation(s)
- Scott Messenger
- Laboratory for Space Sciences and Physics Department, Washington University, St. Louis, MO 63130, USA
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Turner PV, Albassam MA, Walker RM. The effects of overnight fasting, feeding, or sucrose supplementation prior to necropsy in rats. Contemp Top Lab Anim Sci 2001; 40:36-40. [PMID: 11451394] [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: 02/20/2023]
Abstract
This study was designed to investigate the acute effects on routine hematology, serum biochemistry, gastrointestinal contents and weight, and liver weight and morphology due to overnight sucrose feeding of rats prior to necropsy. Groups of rats (five males and five females/group) were fasted overnight, fed chow, or fed sucrose and were euthanized approximately 17 h later. At necropsy, blood was obtained for hematology and serum biochemistry profiling, and the livers and gastrointestinal tracts were weighed and examined. The livers also were evaluated microscopically. The blood glucose and urea nitrogen concentrations and liver weights of animals fed sucrose differed significantly from those of the other groups. Alterations were more striking in males than females. Marked histological changes were present in livers from animals fed sucrose prior to necropsy compared with fasted or chow-fed animals, and these changes were attributed to increased glycogen deposition in the sucrose-fed animals. Because of alterations in hepatic structure and function, we cannot recommend the practice of feeding sucrose to rats prior to necropsy for toxicology studies or any studies examining hepatic function.
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Affiliation(s)
- P V Turner
- Pfizer Global Research and Development - Sheridan Park Laboratories, Mississauga, Ontario, L5K 1B4, Canada
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Affiliation(s)
- D R Jones
- Department of Immunology, Queen's Medical Centre, Nottingham, UK
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Walker RM, Romano G, Davies AH, Theodorou NA, Springall RG, Carter SS. Pressure flow study data in a group of asymptomatic male control patients 45 years old or older. J Urol 2001; 165:683-7. [PMID: 11176458 DOI: 10.1097/00005392-200102000-00094] [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: 11/26/2022]
Abstract
PURPOSE The role of pressure flow studies in the routine evaluation of patients with benign prostatic hyperplasia remains a controversial issue in urological practice. There are little data on age matched asymptomatic control groups. We evaluated pressure flow findings in such a group. MATERIALS AND METHODS A total of 24 male patients 47 to 80 years old (mean age 62.5) attending a general surgical clinic were recruited for study after ethical committee approval. The volunteers had never sought medical attention for urinary symptoms and did not perceive themselves as having a urological problem. Volunteers were assessed by International Prostate Symptom Score (I-PSS) and Madsen symptom score, clinical examination, free uroflowmetry, post-void residual ultrasound, repeat pressure flow studies and transrectal ultrasonography. Pressure flow tracings were manually analyzed for standard urodynamic values and the degree of bladder outflow obstruction according to recognized International Continence Society, Abrams-Griffith nomogram, linear passive urethral resistance relation and urethral resistance factor classifications. RESULTS Median I-PSS was 2.0 (interquartile range 1.2 to 5.7). For I-PSS quality of life the median was 1.0 (interquartile range 0.75 to 2.0). On pressure flow studies 3 patients (13%) had unequivocal obstruction, 7 (29%) were in the equivocal area and 14 (58%) had no obstruction, while 15 (63%) had unstable contractions on medium fill cystometry. CONCLUSIONS The data show that a surprising number of apparently normal men are obstructed by commonly used criteria. This finding confirms asymptomatic obstruction, suggesting that obstruction may be less important in the development of symptoms than previously thought. Also, until the natural history of obstruction is more clearly defined surgery in obstructed asymptomatic patients is probably unwise.
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Affiliation(s)
- R M Walker
- Departments of Urology and Surgery, Charing Cross Hospital, London, United Kingdom
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Abstract
BACKGROUND In Oregon, physicians can prescribe lethal amounts of medication only if requested by competent, terminally ill patients. However, the possibility of extending the practice to patients who lack decisional capacity exists. This paper examines why the legal extension of physician-assisted suicide (PAS) to incapacitated patients is possible, and perhaps likely. METHODS The author reviews several pivotal court cases that have served to define the distinctions and legalities among "right-to-die" cases and the various forms of euthanasia and PAS. RESULTS Significant public support exists for legalizing PAS and voluntary euthanasia in the United States. The only defenses against sliding from PAS to voluntary euthanasia are adhering to traditional physician morality that stands against it and keeping the issue of voluntary euthanasia legally framed as homicide. However, if voluntary euthanasia evolves euphemistically as a medical choice issue, then the possibility of its legalization exists. CONCLUSIONS If courts allow PAS to be framed as a basic personal right akin to the right to refuse treatment, and if they rely on right-to-die case precedents, then they will likely extend PAS to voluntary euthanasia and nonvoluntary euthanasia. This would be done by extending the right to PAS to incapacitated patients, who may or may not have expressed a choice for PAS prior to incapacity.
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Affiliation(s)
- R M Walker
- Division of Medical Ethics and Humanities at the University of South Florida College of Medicine, Tampa 33612-4799, USA
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King LM, Kirby JD, Froman DP, Sonstegard TS, Harry DE, Darden JR, Marini PJ, Walker RM, Rhoads ML, Donoghue AM. Efficacy of sperm mobility assessment in commercial flocks and the relationships of sperm mobility and insemination dose with fertility in turkeys. Poult Sci 2000; 79:1797-802. [PMID: 11194043 DOI: 10.1093/ps/79.12.1797] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Our objectives were to evaluate: 1) the efficacy of the Sperm Mobility Test on commercial turkey farms, and 2) the influence of sperm mobility phenotype on fertility when insemination parameters are varied. In research flocks, differences in sperm mobility among toms are predictive of fertility. We wanted to test the efficacy of this sire selection test in practical, real-world situations, evaluating its usefulness in terms of assessing large numbers of toms, different strains of turkeys, and variable management practices. Utilizing field study results, controlled studies were then conducted to improve test parameters. For the field trials, semen from each of 405 breeder toms (11 strains or lines) was evaluated either in duplicate (n = 285) or in triplicate (n = 120). Sperm mobility was normally distributed among all toms tested, except for one strain. Because the sperm mobility indices for toms evaluated in these field trials were higher than those observed in research flocks, the Sperm Mobility Test was modified to increase the separation between high and low sperm mobility phenotypes by increasing the concentration of Accudenz. To determine the effects of sperm mobility and insemination dose on sustained fertility through time, hens from a research flock were inseminated twice before the onset of lay with sperm from toms classified as high-, average-, or low-mobility in concentrations of 25 to 400 million sperm per artificial insemination dose, and egg fertility was evaluated over a 5-wk period. Toms with the high-mobility sperm phenotype maintained higher fertility (P < 0.05) over the 5-wk period at all insemination doses compared with toms with low-mobility sperm. Toms with high-mobility sperm sired equal numbers of poults in a sperm competition study in which numbers favored low-mobility toms by 3:1. These results demonstrate that the Sperm Mobility Test can be used for on-farm evaluation of semen quality of toms in commercial flocks and that sperm mobility influences fertility and sire fitness.
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Affiliation(s)
- L M King
- Germplasm and Gamete Physiology Laboratory, Agricultural Research Service, USDA, Beltsville, Maryland 20705, USA
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Abstract
The in vitro activity of ABT773, a ketolide antimicrobial agent, was investigated and compared with those of seven other antibiotics. Type strains and 733 Gram-positive, Gram-negative and anaerobic isolates of clinical origin and four CHLAMYDIA: isolates were used. The activity of ABT773 was very similar to that of telithromycin, the other ketolide tested. The MIC(90) was < or = 0.5 mg/L for all bacteria examined except methicillin-resistant Staphylococcus aureus, Enterococcus faecalis, Enterococcus faecium, Haemophilus influenzae and BACTEROIDES: spp. The antichlamydial activity of ABT773 was greater than that of telithromycin, erythromycin and ciprofloxacin. Neither an increase in the size of the inoculm nor the addition of human serum had any marked affect on the in vitro activity of ABT773.
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Affiliation(s)
- J M Andrews
- Department of Medical Microbiology, City Hospital NHS Trust, Dudley Road, Birmingham B18 7QH, UK
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Abstract
Persistent hyperinsulinemic hypoglycemia of infancy (PHHI) is characterized by hyperinsulinism and profound hypoglycemia, with most children requiring pancreatic resection. The histological classification of PHHI is controversial. Most authors acknowledge the existence of focal areas of islet cell proliferation (adenomatosis) in 30%-50% of cases and a diffuse disorganisation of islet architecture, termed "nesidiodysplasia," in others. De Lonlay et al. reported that cases with adenomatosis are focal with normal remainder of pancreas and that focal and diffuse disease can be differentiated intraoperatively, on the basis of increased beta-cell nuclear size found only in the diffusely abnormal pancreas. We have examined pancreatic histology in a blinded controlled study of PHHI patients. Pancreatic tissue was obtained at autopsy from 60 normal subjects (age 17 weeks gestation to 76 years) and from surgical specimens of 31 PHHI patients. Sections from PHHI subjects (n = 294 blocks) and control sections were stained with hematoxylin and eosin, insulin, glucagon, somatostatin, NSE, cytokeratin 19, and vimentin. Three sections from each PHHI patient were randomly chosen for further analysis. Age-matched control (n = 34) and PHHI sections (n = 66) were examined, with the identity of subjects concealed. A diagnosis of normal histology, adenomatosis, or diffuse nesidiodysplasia was recorded for each section. The presence of large beta-cell nuclei (>19 microm), ductuloinsular complexes, and centroacinar cell proliferation was noted. Of a total of 65 subjects examined (34 control and 31 PHHI), 37 subjects were identified as normal on both sections examined. All the control cases were correctly identified as normal and none had large beta-cell nuclei or centroacinar cell proliferation. Of 31 PHHI patients, 28 were identified as abnormal, either on the basis of abnormal architecture and/or abnormally large beta-cell nuclei. Three patients were identified as normal in both sections. Fifteen of 31 patients had diffuse nesidiodysplasia only. Of 13 patients with areas of adenomatosis, 2 had resection of a nodule with adenomatosis present in most of the tissue removed at surgery. Nine patients had a diagnosis of adenomatosis in one section and a diagnosis of diffuse nesidiodysplasia in the other sections from nonadjacent pancreas. Only 2 of 31 PHHI cases had adenomatosis on one section examined and normal pancreas on the other section examined. Large beta-cell nuclei were variably found in PHHI sections. Only 5 of 15 patients with diffuse nesidiodysplasia had large nuclei in both sections examined. Centroacinar cell proliferation was identified in 12 PHHI subjects, 6 with adenomatosis and diffuse nesidiodysplasia and 6 with diffuse changes only. It was patchy in distribution within sections and present in only one section in 7 of the 12 subjects. In summary, we have shown that a blinded observer could differentiate control and PHHI pancreatic tissue. Only 2 of 31 patients (6%) had focal adenomatosis with normal nonadjacent pancreas, the majority (24 of 31) had diffuse nesidiodysplasia affecting the remainder of their pancreas, with 38% (9 of 24) also having areas of adenomatosis. Large beta-cell nuclei did not reliably identify those with diffuse disease in this study. There was evidence of significant ductal and centroacinar proliferation in 39% of PHHI cases, which was not observed in any of the controls. We have shown that PHHI subjects have a spectrum of pancreatic histological abnormalities, from no abnormality to diffuse subtle changes to florid adenomatosis. Patients could not be segregated into subtypes for different operative intervention despite the availability of full immunohistochemical staining.
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Affiliation(s)
- M M Jack
- Department of Paediatric Endocrinology, Mater Children's Hospital, Annerley Road, South Brisbane, Queensland, Australia 4101
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Paola F, Walker RM. Is it ethical to withdraw low-burden interventions in chronically ill patients? JAMA 2000; 284:1380; author reply 1381-2. [PMID: 10989391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
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Affiliation(s)
- W D Doty
- Sacred Heart Regional Heart Institute, Pensacola, Florida, USA
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Paola FA, Walker RM. Deactivating the implantable cardioverter-defibrillator: a biofixture analysis. South Med J 2000; 93:20-3. [PMID: 10653059] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Automatic implantable cardioverter-defibrillators (ICDs) are becoming increasingly common, as is refusal of resuscitative efforts at the end of life, both by patients and surrogate decision-makers. While it is clear that a terminally ill patient who lacks decisional capacity may, through a surrogate, refuse cardiopulmonary resuscitation (CPR), is it appropriate for physicians to infer from such a refusal that the patient's ICD should be deactivated? A proper answer to this question requires consideration of the nature of consent to a do-not-resuscitate (DNR) order, the context in which permission is given for the writing of the DNR order, and the ontologic status of implantable devices in general and ICDs in particular. We introduce the concept of "biofixtures" and suggest that a biofixture analysis is a novel way of approaching the difficult ethical issues that may confound the care of patients with implantable devices.
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Affiliation(s)
- F A Paola
- Department of Internal Medicine, University of South Florida College of Medicine, Tampa 33612-4799, USA
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Affiliation(s)
- R M Walker
- Submarine & Underwater Medicine Unit, HMAS Penguin, Mosman, NSW
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King LM, Song J, Wojcinski ZW, Baker KW, Walker RM. Absence of correlation between telomerase activity and hepatic neoplasia in B6C3F1 mice. Toxicol Lett 1999; 106:247-54. [PMID: 10403669 DOI: 10.1016/s0378-4274(99)00073-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Telomeres are the physical ends of eukaryotic chromosomes, which maintain chromosome stability and are progressively shortened with aging in somatic cells. The enzyme telomerase elongates telometric DNA and while not usually detectable in human somatic cells is expressed in most human tumors. The present study was conducted to determine if telomerase activity is a marker for spontaneous hepatic neoplastic changes in B6C3F1 mice, a strain frequently used in rodent carcinogenicity studies. Telomerase activity was generally higher in microscopically normal liver tissue from 8-week-old compared to aged mice (110-week-old); however, telomerase activity was not consistently increased in hepatocellular adenomas and carcinomas. It is proposed that, while elevated telomerase activity may modulate human tumor development, modulation of telomerase activity is not a feature of hepatic tumors in B6C3F1 mice and therefore is unlikely to have utility as a molecular marker for hepatic neoplasia in this mouse strain.
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Affiliation(s)
- L M King
- Parke Davis Research Institute, Mississauga, Canada.
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Abstract
BACKGROUND: Physicians who treat patients approaching the end of life often face moral, ethical, and legal issues involving shared decision making, futility, the right to refuse medical treatment, euthanasia, and physician-assisted suicide. METHODS: The author examines cases that involve these issues and also reviews the ethical principles that guide current medical practice. Issues such as end-of-life ethical questions, the right to life-sustaining therapy, medical futility, the distinction between killing and allowing to die, and physician-assisted suicide are discussed. RESULTS: The principal problem involves the appropriate use of technology at the end of life. While developments in technology have enhanced our ability to prolong life, issues have also arisen regarding the resulting quality of life, the sometimes marginal benefits to our patients, and the burdens that this technology imposes on patients, families, and society. CONCLUSIONS: Legal and ethical issues continue to confront patients, courts, and physicians. A better understanding of these issues and an awareness of the availability of effective palliative care will help physicians, patients, and families adequately address the end-of-life issues that are an intrinsic part of medical care.
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Affiliation(s)
- RM Walker
- Division of Medical Ethics and Humanities, University of South Florida College of Medicine, Tampa, Florida 33612-4799, USA
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Manca D, Walker RM, Krishna G, Graziano MJ, Kropko ML. Probabilistic approach to the establishment of maximal content limits of impurities in drug formulations: the case of parenteral diphenylhydantoic acid. Regul Toxicol Pharmacol 1999; 29:1-14. [PMID: 10051414 DOI: 10.1006/rtph.1998.1275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Diphenylhydantoic acid (DPHA) is a degradation product in parenteral formulations of the anticonvulsant phenytoin and the prodrug fosphenytoin. DPHA has also been reported to be a minor metabolite of phenytoin. Levels found in the urine of various species, including humans, after oral or intravenous (iv) phenytoin ranged from undetected to a few percent of administered dose. In the present analysis, the toxicologic profile of DPHA was integrated with exposure data in order to characterize its safety under recommended clinical regimens of fosphenytoin administration. In preclinical safety studies, DPHA was without effect in the Ames assay and at concentrations up to 3000 microg/plate in the presence or absence of metabolic activation, and in the in vitro micronucleus test with acute and 2-week repeated dose studies in Wistar rats at iv doses up to 15 mg/kg. In 4-week studies conducted in rats and dogs receiving fosphenytoin containing DPHA levels up to 1.1%, and in an in vitro structural chromosome aberration test with DPHA levels up to 2.0%, all findings were consistent with known effects of phenytoin (such as CNS signs and increased liver weight), and none were attributed to DPHA. Reports in the literature indicate that in murine in vivo and in vitro models, DPHA has much lower potential for reproductive toxicity than phenytoin. A no-observed-effect level (NOEL) of 15 mg/kg established from the 2-week study in rats was used with probabilistic techniques to estimate tolerable daily doses (TDDs) of DPHA. In this approach, interspecies correction was performed by allometrically scaling the NOEL based on a distributional power of body weight while intraindividual variability was accounted for by selecting the lower percentiles of the population-based distribution of TDDs. The results indicate that a DPHA content limit of 3.0% in an administered dose of fosphenytoin is unlikely to cause adverse effects in patients.
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Affiliation(s)
- D Manca
- Pathology and Experimental Toxicology, Parke-Davis Pharmaceutical Research Division, Warner-Lambert Co., Mississauga, Ontario, Canada.
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Paola FA, Malik TK, Walker RM. Poison pen letters, due process, and medical schools' policies toward anonymous correspondence that disparages medical school faculty. Acad Med 1998; 73:534-537. [PMID: 9609868 DOI: 10.1097/00001888-199805000-00023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
PURPOSE To learn more about the frequency of and response to poison pen letters (anonymous correspondence that disparages faculty members) in academic medicine. METHOD The authors surveyed all 143 deans of medical schools that are members of the AAMC about their practices and policies regarding the handling of poison pen letters. RESULTS Of the deans surveyed, 119 (83%) responded. Sixty-seven deans (56%) reported having received poison pen letters during their tenure. Of those, 16 (24%) reported that they had discarded the letters based solely on the anonymity of the authors. The remaining 51 deans (76%) reported that they had either sequestered, investigated, or placed the letters into the faculty members' files, or that they had based their decisions to discard the letters on factors other than the authors' anonymity. Only one dean reported having a written policy for handling such correspondence. CONCLUSION This survey of AAMC schools indicates that poison pen letters are not uncommon. The authors recommend a policy by which anonymous letters that disparage current or prospective faculty members would be categorically discarded.
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Affiliation(s)
- F A Paola
- Division of Medical Ethics and Humanities, University of South Florida, College of Medicine, Tampa 33612-4799, USA.
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Walker RM, Patel A, St Clair Carter S. Is there a clinically significant change in pressure-flow study values after urethral instrumentation in patients with lower urinary tract symptoms? Br J Urol 1998; 81:206-10. [PMID: 9488059 DOI: 10.1046/j.1464-410x.1998.00531.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE To determine the effect of urethral instrumentation on pressure-flow study values and subsequent grading of bladder outflow obstruction (BOO) in men with lower urinary tract symptoms (LUTS) using suprapubic intravesical pressure monitoring. PATIENTS AND METHODS Seventy-two men with LUTS underwent pressure-flow study using suprapubic intravesical pressure monitoring. The urethra was then instrumented successively with a 12 F catheter and a 17 F cystoscope, and a further pressure-flow study recorded after each procedure. Standard pressure-flow variables were measured for the three recordings. The presence and degree of obstruction were determined using commonly recognized grading systems, i.e. the Abrams-Griffiths nomogram. the linear passive urethral resistance ratio (LPURR) and the urethral resistance algorithm (URA). RESULTS There were statistically significant differences in the detrusor pressure at maximum flow and detrusor opening pressure between the uninstrumented and instrumented studies (12 F and 17 F) but no difference in peak flow rates between the groups or in the Abrams-Griffiths number or URA value between studies. Using the LPURR, there was a tendency to a lower obstruction class after urethral instrumentation, ranking as 17 F > 12 F > no instrumentation. CONCLUSIONS The changes seen after urethral instrumentation represent no more than the biological intra-individual variation normally seen in pressure-flow studies and do not lead to a clinically significant change in obstruction class.
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Affiliation(s)
- R M Walker
- Department of Urology, Charing Cross Hospital, London, UK
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Walker RM, Di Pasquale B, Hubregtse M, St Clair Carter S. Pressure-flow studies in the diagnosis of bladder outlet obstruction: a study comparing suprapubic and transurethral techniques. Br J Urol 1997; 79:693-7. [PMID: 9158503 DOI: 10.1046/j.1464-410x.1997.00143.x] [Citation(s) in RCA: 19] [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] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE To compare suprapubic and transurethral methods of measuring intravesical pressure in a group of men undergoing investigation for lower urinary tract symptoms (LUTS), to identify which urodynamic variables are affected by the presence of an urethral catheter during the voiding phase, and consequently whether there is any change in the grading of bladder outflow obstruction (BOO) using the commonly recognised grading systems. PATIENTS AND METHODS Thirty-five men with LUTS underwent both suprapubic and transurethral pressure-flow studies during a single session. Standard pressure flow variables were measured in all patients with both methods, enabling calculation of obstruction using the commonly used grading systems, i.e. the Abrams-Griffith number, linear passive urethral resistance ratio (LPURR) and urethral resistance algorithm (URA). RESULTS There were statistically significant differences between the methods in the mean values of maximum flow rate and the detrusor pressure at that maximum: 60% of men were in the same LPURR class with either method. Using the transurethral method, 26% of patients increased the LPURR class by one and 6% by two classes. Using the Abrams-Griffiths nomogram, 17% moved from a classification of equivocal to obstructed and 3% from unobstructed to equivocal. Using the criterion of a value of URA > 29, 57% were obstructed using the suprapubic and 74% using the transurethral method. CONCLUSION According to the method used, there were differences in the classification of obstruction between the suprapubic and transurethral routes; transurethral studies tended to indicate greater obstruction. The interpretation of urodynamic studies should take into account the technique used and where the route is transurethral, the smallest catheter available should be used.
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Affiliation(s)
- R M Walker
- Department of Urology, Charing Cross Hospital, London, UK
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Hofstra AH, King LM, Walker RM. Early effects of CI-924 on hepatic peroxisome proliferation, microsomal enzyme induction, PCNA, and apoptosis in B6C3F1 mice and Wistar rats. Arch Toxicol 1997; 71:250-7. [PMID: 9101042 DOI: 10.1007/s002040050384] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The lipid lowering agent 5,5'[[1,1'-biphenyl]-2,5-diylbis(oxy)]bis[2,2-dimethylpentanoic acid] (CI-924) is a peroxisome proliferator in rats and mice, but increased the incidence of hepatic tumors in mice only. Male and female B6C3F1 mice and albino Wistar rats were treated with CI-924 at doses of 0, 25 and 75 mg/kg for 1, 3, 7 and 28 days. Our aim was to identify species differences potentially related to tumorigenicity and to establish the time course of early events related to or associated with peroxisome proliferation. After 24 h of exposure to CI-924 in the diet there were increases in carnitine acyl transferase and CYP4A1 activity in mice at 25 and 75 mg/kg. In rats, carnitine acyl transferase activity was increased after 24 h and CYP4A1 activity increased after 3 days at 75 mg/kg. Acyl CoA oxidase activity was increased at both doses in male and female rats and mice by 3 days. In general the changes in enzyme activity were of greater magnitude in rats. In contrast to the rapid peroxisome proliferation, increases in the amount of PCNA were observed in CI-924 treated rats and mice at later times after administration and only at 75 mg/kg. PCNA was increased to a similar extent in both rats and mice, while apoptosis was decreased at both doses of CI-924 after 3 days in female rats, 7 days in male rats, and was largely unchanged in mice. It was concluded that the sequence of peroxisome proliferation was generally similar in rats and mice. Early changes in cell proliferation and programmed cell death were not directly correlated with subsequent CI-924-induced hepatotumorigenicity.
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Affiliation(s)
- A H Hofstra
- Parke Davis Research Institute, Mississauga, Ontario, Canada
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Schonwetter RS, Walker RM, Solomon M, Indurkhya A, Robinson BE. Life values, resuscitation preferences, and the applicability of living wills in an older population. J Am Geriatr Soc 1996; 44:954-8. [PMID: 8708307 DOI: 10.1111/j.1532-5415.1996.tb01867.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [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: 02/01/2023]
Abstract
OBJECTIVES To determine whether life values are related to resuscitation preferences and living will completion in an older population and to assess beliefs about the applicability of living wills. DESIGN Individual structured interviews. SETTING An independent retirement community. PARTICIPANTS One hundred thirty-two subjects older than 63 years of age. MEASUREMENTS Resuscitation preferences were elicited in five hypothetical scenarios. Subjects with living wills were asked whether their living will would play a role in the scenarios. Subjects rated the importance of 13 life value statements. RESULTS The percentage of subjects desiring CPR in each scenario was as follows: current condition (66%); acute illness (33%); terminal disease (8%); functional impairment (8%); and dementia (7%). The percentage of those with a living will who thought their living wills would play a role in the scenarios was as follows: acute illness (84%); terminal disease (93%); functional impairment with intact cognition (66%); and dementia (91%). Factor analysis of the life value statements revealed five meaningful factors: quality of life; capacity/autonomy; family relations; physical comfort; and treatment philosophy. Multiple correlations were found between four of five life value factors and hypothetical resuscitation preferences or the presence of a living will. CONCLUSION Subjects misinterpreted the applicability of living wills in nonterminal illness scenarios. A relationship between life values and resuscitation preferences was noted, which emphasizes the importance of eliciting and including life values when discussing advance directives.
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Affiliation(s)
- R S Schonwetter
- Division of Geriatric Medicine, University of South Florida College of Medicine, Tampa 33612, USA
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Walker RM, Wojcinski ZW, Hofstra AH, King LM, Rogers JE, Baker KW, Chang PK, Smith GS. Hepatotumorigenicity and peroxisome proliferation induced by the hypolipidemic CI-924 in a two-year study in male and female B6C3F1 mice. Toxicol Pathol 1996; 24:265-72. [PMID: 8736381 DOI: 10.1177/019262339602400301] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The hepatic tumorigenicity of CI-924 (5,5'-(1,1'-biphenyl)-2,5-diylbis(oxy)(2,2-dimethylpentanoic acid)), a hypolipidemic agent, was evaluated in 50 B6C3F1 mice/sex/dose given drug in the diet at 0, 5, 25, and 75 mg/kg/day for 2 yr. Peroxisomal and drugmetabolizing enzyme determinations, as well as ultrastructural evaluations, were conducted in subsets of these same groups, because drugs of this class cause peroxisome proliferation and hepatic tumors in rodents. CI-924 elicited dose-dependent increases in the incidence of hepatocellular adenomas and carcinomas in both sexes that were statistically significant at 75 mg/kg. Stereologic evaluation revealed significant increases in hepatocellular peroxisome volume ratio, due to increased numbers of peroxisomes, in females at all doses and males at 75 mg/kg. Peroxisomal enzyme activity measurements revealed no change in catalase, but dose-dependent increases in carnitine acetyltransferase and cyanide-insensitive beta-oxidation in both sexes. Peroxisome proliferation, determined biochemically or ultrastructurally, was twice as great in females compared to males. Total cytochrome P-450 was increased in both sexes given 75 mg/kg. There were dose-dependent decreases in glutathione S-transferase in males and increased glutathione peroxidase in both sexes at 25 and 75 mg/kg. In conclusion, this study demonstrated that while CI-924 induced hepatic tumors in male and female B6C3F1 mice the associated peroxisome proliferation, while moderate in females, was only weak in the males after 2 yr of exposure.
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Affiliation(s)
- R M Walker
- Parke-Davis Research Institute, Mississauga, Ontario, Canada.
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Abstract
This study reported a lower than expected prevalence of advance directives among hospice patients. The presence of an advance directive was related to certain sociodemographic factors, diagnosis, and previous physician-patient advance directive discussions. Barriers that precluded the completion of an advance directive primarily involved a lack of physician-patient advance directive discussions or a lack of patient understanding. This study confirmed the importance of physician-patient discussion toward completion of an advance directive. Improving physician-patient communication about this issue should increase the prevalence of advance directive completion among hospice patients.
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Hofstra AH, King LM, Walker RM. Peroxisome proliferation and microsomal enzyme induction by the hypolipidemic CI-924 in rats and mice: relationship to tumorgenicity. Fundam Appl Toxicol 1995; 27:277-86. [PMID: 8529824 DOI: 10.1006/faat.1995.1134] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
CI-924 (5'5'-[1,1'-biphenyl]-2,5-diylbis(oxy)]bis [2,2-dimethyl-pentanoic acid]), a lipid lowering agent, was previously shown to be hepatotumorigenic in male and female B6C3F1 mice but not in male and female albino Wistar rats. To determine if the difference between the species in tumorigenic response correlated with the extent of peroxisome proliferation or microsomal changes the effects of CI-924 on liver were characterized in rats and mice. CI-924 doses of 0, 25, 75, and 150 mg/kg were administered in the diet for 4 weeks to B6C3F1 mice and albino Wistar rats. Peroxisomal beta-oxidation activity was significantly increased in all groups at doses of 25 mg/kg or higher and was induced up to 25 times in male rats. Peroxisomal carnitine acyltransferase and acyl-CoA oxidase activities were also increased, with the greatest induction observed in male rats. Catalase activity quadrupled in rats and doubled in mice. Serum liver enzyme activities were unchanged with the exception of 5'nucleotidase which was elevated in mice and decreased in male, but not female, rats. Glutathione S-transferase decreased in the males of both species and glutathione peroxidase increased in the mice. Cytochrome P450 4A1 increased in both species at doses of 25 mg/kg or greater and correlated with increased lauric acid hydroxylation. The high degree of peroxisome proliferation in male rats was unexpected in light of the lack of tumorgenicity demonstrated in a previous 2-year study and these results indicate that early peroxisome proliferation alone is not always a good predictor of hepatocarcinogenicity.
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Affiliation(s)
- A H Hofstra
- Parke Davis Research Institute, Mississauga, Ontario, Canada
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Symon P, Walker RM. A Consumer Perspective on Performance Indicators: The Local Housing Authority Reports to Tenants Regimes in England and Wales. ACTA ACUST UNITED AC 1995. [DOI: 10.1068/c130195] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Performance indicators were formally introduced into local authority housing management in England and Wales by Section 167(1) of the 1989 Local Government and Housing Act, which required local housing authorities to circulate annual Reports to Tenants (RTTs) containing information on performance indicators. In this paper, the background to the new regime is discussed, noting the absence of a consumer perspective on performance indicators in much of the research literature. There is an examination of the appropriateness of the concepts of client, customer, consumer, and citizen as descriptions of tenants. The reaction of tenants in England and Wales to the first year of RTTs is then discussed. The impact on tenants was minimal, and consumers did not use the information in the reports in the way central government might have hoped. The value to tenants of the growing number of RTTs regimes is questioned. The paper concludes with a criticism of the concept of tenants as consumers in the context of RTTs regimes, and points to the inherent conflicts within these regimes.
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Affiliation(s)
- P Symon
- Centre for Urban and Regional Studies, School of Public Policy, University of Birmingham, Edgbaston, Birmingham B15 2TT, England
| | - R M Walker
- Centre for Housing Management and Development, Department of City and Regional Planning, University of Wales College of Cardiff, PO Box 906, Cardiff CF1 3YN, Wales Received 21 April 1994; revised 15 August 1994
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Walker RM, Schonwetter RS, Kramer DR, Robinson BE. Living wills and resuscitation preferences in an elderly population. Arch Intern Med 1995; 155:171-175. [PMID: 7811126] [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 Living wills are considered clear and convincing evidence of a person's preferences for end-of-life treatment. Unfortunately, living wills often use vague language that forces physicians and others to infer specific treatment choices, like the choice to forgo cardiopulmonary resuscitation (CPR). To test the validity of such inferences we examined the relationship between living will completion and CPR preference. We also examined whether CPR choices were fixed or could be influenced by detailed information on CPR. METHODS We interviewed 102 retired elderly persons, many of whom had living wills. We obtained CPR preferences in five hypothetical scenarios before and after providing CPR information. We then analyzed differences in desire for CPR between the group of subjects with living wills and the group without. RESULTS In each scenario there were subjects in both groups who desired CPR. The group with living wills desired less CPR in scenarios involving functional impairment and cognitive impairment, but not in scenarios involving current health, severe illness, and terminal illness. After receiving CPR information, both groups changed their preferences such that intergroup differences were no longer seen. CONCLUSIONS Preferences for CPR among subjects with living wills are not homogeneous, but distributed across the clinical scenarios. Therefore, one cannot infer CPR preference from the mere presence of a living will. Cardiopulmonary resuscitation information can influence preferences even among persons with living wills, implying that preferences are neither fixed nor always based on adequate information. Physicians should view vaguely worded documents as unreliable expressions of treatment preference that should not supplant informed discussion.
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Affiliation(s)
- R M Walker
- Division of Medical Ethics and Humanities, University of South Florida College of Medicine, Tampa
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Abstract
Effects of cycle ergometer conditioning (heart rate 143 +/- 2 beats/min, 25 min/session, 3 sessions/wk) during the second and third trimesters of pregnancy were studied in 18 healthy previously sedentary women. A nonexercising control group (n = 9) was also studied. Graded exercise tests were conducted for both groups at approximately 17, 27, and 37 wk of gestation and at 20 wk postpartum. Both groups exhibited augmented ventilatory responses to exercise throughout pregnancy. Significant aerobic conditioning effects observed in the exercised group between entry and third trimester of pregnancy testing included a 17% increase in oxygen pulse at peak exercise, reduction in the respiratory exchange ratio during standard submaximal exercise, and an increase in work rate at the onset of blood lactate accumulation. Onset of blood lactate accumulation did not change significantly in the control group. Respiratory exchange ratio at peak exercise was higher in postpartum tests compared with those conducted in late gestation in both groups. Peak postexercise lactate levels were also significantly lower in second and third trimesters of pregnancy testing compared with postpartum in the control group. This effect appeared to be prevented by physical conditioning in the exercised group. The study results support the hypothesis that moderate aerobic conditioning increases maximal aerobic power and the capacity for sustained submaximal exercise. Chronic exercise also appeared to help to preserve anaerobic working capacity in late gestation.
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Affiliation(s)
- L A Wolfe
- School of Physical and Health Education, Queen's University, Kingston, Ontario, Canada
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Abstract
Morphological changes in mitochondria are observed early in the course of acetaminophen (AA)-induced hepatotoxicity, and mitochondrial dysfunction has been observed both in vivo and in vitro following exposure to AA. This study examined the early effects of AA exposure in vivo on mitochondrial respiration and evaluated the effectiveness of N-acetyl-L-cysteine (NAC) in protecting against respiratory dysfunction. Mitochondria were isolated from the livers of fasted, male CD-1 mice 0, 0.5, 1, 1.5 or 2 h after administration of a hepatotoxic dose of AA (750 mg/kg). Glutamate- and succinate-supported mitochondrial respiration were subsequently assessed by polarographic measurement of state 3 (ADP-stimulated) and state 4 (resting) rates of oxygen consumption and determination of the corresponding respiratory control ratios (RCR: state 3/state 4) and ADP:O ratios. Hepatotoxicity was assessed histologically and by measuring plasma alanine aminotransferase (ALT) activity. The earliest sign of mitochondrial dysfunction observed in this study was a significant decrease in the ADP:O ratio for the oxidation of glutamate 1 h post-dosing. At 1.5 and 2 h post-dosing the RCRs for both glutamate- and succinate-supported respiration were significantly decreased. All of the respiratory parameters measured in this study were significantly decreased, with the exception of succinate-supported state 4 respiration which was significantly increased, 2 h after AA administration. Thus, inhibition of mitochondrial respiration preceded overt hepatic necrosis, indicated by an elevation of ALT activity, which was not observed until 3 and 4 h post-dosing. In addition, mitochondrial respiratory dysfunction correlated with morphological alterations.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- P J Donnelly
- Department of Pharmacology and Toxicology, Faculty of Medicine, Queen's University, Kingston, Ontario, Canada
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Clemett SJ, Maechling CR, Zare RN, Swan PD, Walker RM. Identification of Complex Aromatic Molecules in Individual Interplanetary Dust Particles. Science 1993; 262:721-5. [PMID: 17812337 DOI: 10.1126/science.262.5134.721] [Citation(s) in RCA: 264] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Seventeen stratospherically collected particles-eight of which are classified as interplanetary dust particles (IDPs), seven of which are classified as probable terrestrial contaminants, and two of which have uncertain origins-were studied with a microprobe two-step laser mass spectrometer. Many polycyclic aromatic hydrocarbons(PAHs) and their alkylated derivatives were identified in two of the eight IDPs. The PAHs observed include a high-mass envelope not found in meteorites or terrestrial contaminants and prominent odd-mass peaks suggestive of nitrogen-containing functional groups attached to aromatic chromophores. In addition, the complexity of the IDP mass spectra has no precedence in previous studies of meteorite samples or their acid residues. Extensive checks were performed to demonstrate that the PAH signals are not caused by terrestrial contaminants.
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Houston BJ, Macallum GE, Walker RM, Albassam MA, Gough A, Smith GS. Toxicity of CI-949, a novel anti-allergy agent. Fundam Appl Toxicol 1993; 21:376-83. [PMID: 8258391 DOI: 10.1006/faat.1993.1110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The toxicity of CI-949, an effective inhibitor of allergic mediator release in pharmacology models, was evaluated in rodents and dogs. Median lethal doses at 24-hr postdose ranged from 343 to 453 mg/kg in mice and 806 to 2058 mg/kg in rats. Delayed toxicity was observed at 300 mg/kg and greater in mice and at 500 mg/kg and greater in rats. Mortality and clinical intolerance occurred in rats at 200 and 400 mg/kg in the subacute studies, and at 100 and 150 mg/kg in the 13-week study. In rats, dose-dependent lymphoid tissue atrophy and depletion or necrosis of lymphocytes in lymphoid tissues were seen in deaths and moribund terminations. Although doses up to 60 mg/kg administrated for 2 weeks to dogs were well tolerated, 60 and 120 mg/kg in the 13-week dog study were poorly tolerated. Cutaneous sores, mucocutaneous purulent discharge, emesis, diarrhea, and weight loss were identified at these lethal doses. Histopathologic changes in dogs included myocardial, vascular and soft tissue inflammation, and gastric ulceration at 60 and 120 mg/kg, and thymic atrophy at 20 mg/kg and greater. Doses of 10 and 50 mg/kg were no-effect doses in 13-week repeated dose studies in dogs and rats, respectively. These results were used to support initial human clinical trials of CI-949.
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Affiliation(s)
- B J Houston
- Parke-Davis Research Institute, Mississauga, Ontario, Canada
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Abstract
Sprague-Dawley rats were exposed for 6 h daily to 0.8 ppm of ozone and 14.4 ppm of nitrogen dioxide. Approximately 7 to 10 wk after the initiation of exposure, animals began to demonstrate respiratory insufficiency and severe weight loss. About half of the rats died between Days 55 and 78 of exposure; no overt ill effects were observed in animals exposed to filtered air, to ozone alone, or to nitrogen dioxide. Biochemical findings in animals exposed to ozone and nitrogen dioxide included increased lung content of DNA, protein, collagen, and elastin, which was about 300% higher than the control values. The collagen-specific crosslink hydroxy-pyridinium, a biomarker for mature collagen in the lung, was decreased by about 40%. These results are consistent with extensive breakdown and remodeling of the lung parenchyma and its associated vasculature. Histopathologic evaluation showed severe fibrosis, alveolar collapse, honeycombing, macrophage and mast cell accumulation, vascular smooth muscle hypertrophy, and other indications of severe progressive interstitial pulmonary fibrosis and end-stage lung disease. This unique animal model of progressive pulmonary fibrosis resembles the final stages of human idiopathic pulmonary fibrosis and should facilitate studying underlying mechanisms and potential therapy of progressive pulmonary fibrosis.
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Affiliation(s)
- J A Last
- Department of Internal Medicine, School of Medicine, University of California, Davis 95616-8542
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Abstract
OBJECTIVE To assess the relationship between cardiopulmonary resuscitation (CPR) information and desire for CPR in an elderly population and to determine the influence of outcome data on desire for CPR in older persons. DESIGN An interventional study utilizing an educational program. SETTING Elderly independent retirement community. PARTICIPANTS One hundred two persons, all more than 62 years old, who were neither demented nor depressed. INTERVENTION Participants received an educational intervention consisting of descriptive CPR information and quantitative information about CPR outcomes. CPR information, survival estimates, and preferences were recorded prior to and after the intervention. MEASUREMENTS AND MAIN RESULTS Subjects exhibited a high level of basic knowledge about CPR, which did not change with the intervention. While subjects consistently overestimated their chances of survival post CPR, these estimates decreased toward more realistic levels after the intervention (p < 0.001). CPR preferences changed in three of five hypothetical clinical scenarios after the intervention (p < 0.05). Those who were more realistic in their estimates of CPR survival desired less CPR in the hypothetical scenarios (p < 0.01). A trend in our data suggest that quantitative outcome information may have a greater influence on CPR preferences than has descriptive information (p = 0.07). CONCLUSIONS CPR preferences changed after an educational intervention. An improved understanding of quantitative outcome data appears to influence the desire for CPR and therefore should be included in CPR discussions with older patients.
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Affiliation(s)
- R S Schonwetter
- Division of Geriatric Medicine, University of South Florida College of Medicine, Tampa 33612-4799
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Schonwetter RS, Walker RM. Advance directives for medical care. J Fla Med Assoc 1992; 79:181-5. [PMID: 1573383] [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] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- R S Schonwetter
- Division of Geriatric Medicine, University of South Florida College of Medicine
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Walker RM. DNR in the OR. Resuscitation as an operative risk. JAMA 1991; 266:2407-12. [PMID: 1717723] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Should do-not-resuscitate (DNR) orders be routinely rescinded when terminally ill patients undergo palliative surgery? If so, patients will be forced to balance the benefits of palliative surgery against the risks of unwanted resuscitation. If physicians are required to honor intraoperative DNR orders, they may feel unacceptably restrained from correcting adverse effects for which they feel responsible. This dilemma has been overlooked by DNR policies. This article argues for the permissibility of honoring intraoperative DNR orders. The patient's right to refuse treatment outweighs physicians' concerns about professional scrutiny over intraoperative deaths. Physicians' moral concerns about hastening patient death are important but may be assuaged by (1) emphasizing patients' acceptance of operative mortality risk; (2) viewing matters as analogous to surgery on Jehovah's Witnesses who refuse lifesaving transfusion; (3) viewing the patient's intraoperative death as a double effect, that is, an unintended negative effect that is linked to the performance of a good act (palliation); and (4) distinguishing this from assisted suicide.
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Affiliation(s)
- R M Walker
- Department of Internal Medicine, University of South Florida College of Medicine, Tampa 33612-4799
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Abstract
OBJECTIVE To understand the kinds of clinical situations physicians and nurses regard as "ethics problems." DESIGN The authors prospectively studied physicians' and nurses' perceptions of ethics problems using paired interviews. Individual interviews were conducted with physicians and nurses as they cared for the same patients during a six-week period. Each was asked whether any ethics problems had arisen in the care of his or her patients and, if so, to give a brief description of each problem. SETTING Three general medical services in a 497-bed community teaching hospital. PARTICIPANTS 13 physicians (mostly family medicine residents) and 42 nurses caring for 142 patients. MAIN RESULTS The physicians and nurses thought ethics problems were present in 75 of the 142 patients cases. Physicians and nurses identified ethics problems with similar frequencies; however, they often identified ethics problems in different patient cases or identified different ethics problems in the same case. Physicians and nurses described a variety of problem types. Physicians identified more problems related to quality of life, inappropriate hospital admissions, and cost of care; nurses identified more problems related to patient preferences, family wishes, pain management, implementing treatments, and discharge planning. A fourth of the ethics problems identified by physicians and nurses involved interstaff conflicts. CONCLUSIONS The physicians and nurses studied considered a broad range of clinical situations to be "ethics problems," and they perceived them to occur frequently. Systematic differences were found between physicians' and nurses' perceptions of ethics problems, and many ethics problems generated interstaff conflicts. Incorporating this kind of information into clinical ethics education programs, and into hospital policies, may represent a useful approach toward improving physician-nurse interaction.
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Affiliation(s)
- R M Walker
- Department of Internal Medicine, University of South Florida College of Medicine, Tampa 33612-4799
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