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Cheitlin MD, Gerstenblith G, Hazzard WR, Pasternak R, Fried LP, Rich MW, Krumholz HM, Peterson E, Reves JG, McKay C, Saksena S, Shen WK, Akhtar M, Brass LM, Biller J. Database Conference January 27-30, 2000, Washington D.C.--Do existing databases answer clinical questions about geriatric cardiovascular disease and stroke? THE AMERICAN JOURNAL OF GERIATRIC CARDIOLOGY 2001; 10:207-23. [PMID: 11455241 DOI: 10.1111/j.1076-7460.2003.00696.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
EXECUTIVE SUMMARY: Most randomized, controlled trials evaluating the effectiveness of pharmaceutical, surgical, and device interventions for the prevention and treatment of cardiovascular disease have excluded patients over 75 years of age. Consequently, the use of these therapies in the older population is based on extrapolation of safety and effectiveness data obtained from younger patients. However, there are many registries and observational databases that contain large amounts of data on patients 75 years of age and older, as well as on younger patients. Although conclusions from such data are limited, it is possible to define the characteristics of patients who did well and those who did poorly. The goal of this conference was to convene the principal investigators of these databases, and others in the field of geriatric cardiology, to address questions relating to the safety and effectiveness of treatment interventions for several cardiovascular conditions in the elderly. Seven committees discussed the following topics: (I) Risk Factor Modification in the Elderly; (II) Chronic Heart Failure; (III) Chronic Coronary Artery Disease: Role of Revascularization; (IV) Acute Myocardial Infarction; (V) Valve Surgery in the Elderly; (VI) Electrophysiology, Pacemaker, and Automatic Internal Cardioverter Defibrillators Databases; (VII) Carotid Endarterectomy in the Elderly. The chairs of these committees were asked to invite principal investigators of key databases in each of these areas to discuss and prepare a written statement concerning the available safety and efficacy data regarding interventions for these conditions and to identify and prioritize areas for future study. The ultimate goal is to stimulate further collaborative outcomes research in the elderly so as to place the treatment of cardiovascular disease on a more scientific basis.
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Samali A, Robertson JD, Peterson E, Manero F, van Zeijl L, Paul C, Cotgreave IA, Arrigo AP, Orrenius S. Hsp27 protects mitochondria of thermotolerant cells against apoptotic stimuli. Cell Stress Chaperones 2001; 6:49-58. [PMID: 11525243 PMCID: PMC434383 DOI: 10.1379/1466-1268(2001)006<0049:hpmotc>2.0.co;2] [Citation(s) in RCA: 134] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Enhanced cell survival and resistance to apoptosis during thermotolerance correlates with an increased expression of heat shock proteins (Hsps). Here we present additional evidence in support of the hypothesis that the induction of Hsp27 and Hsp72 during acquired thermotolerance in Jurkat T-lymphocytes prevents apoptosis. In thermotolerant cells, Hsp27 was shown to associate with the mitochondrial fraction, and inhibition of Hsp27 induction during thermotolerance in cells transfected with hsp27 antisense potentiated mitochondrial cytochrome c release after exposure to various apoptotic stimuli, despite the presence of elevated levels of Hsp72. Caspase activation and apoptosis were inhibited under these conditions. In vitro studies revealed that recombinant Hsp72 more efficiently blocked cytochrome c-mediated caspase activation than did recombinant Hsp27. A model is presented for the inhibition of apoptosis during thermotolerance in which Hsp27 preferentially blocks mitochondrial cytochrome c release, whereas Hsp72 interferes with apoptosomal caspase activation.
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Abstract
Asymmetries in the surface temperature of the fingertips of the right and left hands were gathered on four independent samples of children ranging in age from 4 to 8 years (N = 398) while watching film clips in order to determine if the direction or magnitude of asymmetry was related to behavioral signs of fear or inhibition. The left index finger was cooler than the right index finger for all four groups. The right ring finger was cooler than the left ring finger for two of the four groups, and of similar temperature for the other two groups. There was no relation between direction of asymmetry and behavior and only a modest relation between a large temperature asymmetry between the index fingers and behavioral signs of very high fear or inhibition. There was no relation between asymmetry and fear or inhibition across all children, suggesting the utility of examining extreme scores.
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Rojas K, Serrano de la Peña L, Gallardo T, Simmons A, Nyce K, McGrath R, Considine E, Vasko AJ, Peterson E, Grady D, Cox R, Andrew LJ, Lovett M, Overhauser J, Williams CJ. Physical map and characterization of transcripts in the candidate interval for familial chondrocalcinosis at chromosome 5p15.1. Genomics 1999; 62:177-83. [PMID: 10610710 DOI: 10.1006/geno.1999.5997] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The gene for familial chondrocalcinosis (MIM 118600; gene symbol CCAL2) has been localized to a 0.8-cM interval on the short arm of chromosome 5, between the polymorphic microsatellite markers D5S416 and D5S2114. We have undertaken the physical and transcript mapping of this interval, as well as regions telomeric to the interval, in an attempt to define ultimately the gene for this disorder. The physical map is composed of YAC, BAC, PAC, and cosmid resources and spans a physical distance of approximately 0.3 Mb. Using cDNA selection, we have identified eight novel transcripts in and around the interval; two of the selected transcripts reside in the candidate interval. We have also more precisely placed several expressed sequence tags (ESTs) that were previously mapped by radiation hybrid analysis and were reported to reside in or near the candidate interval. Two of the ESTs analyzed overlap with the selected cDNAs that reside in the candidate interval. All of the selected cDNAs are expressed partial transcripts, as determined by Northern blot analysis, and using RT-PCR analysis, we have determined that the cDNAs that reside in the candidate interval are expressed in cartilage and synovium, tissues that are presumably relevant to the chondrocalcinosis phenotype.
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80
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Joseph CL, Foxman B, Leickly FE, Peterson E, Ownby D. Sensitivity and specificity of asthma definitions and symptoms used in a survey of childhood asthma. J Asthma 1999; 36:565-73. [PMID: 10524539 DOI: 10.3109/02770909909087293] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
We compared the ability of definitions/symptoms of asthma to identify urban, elementary schoolchildren with physician-diagnosed asthma and bronchial hyperresponsiveness (BHR) post-exercise challenge. Definitions of asthma from the literature were compared, including American Thoracic Society (ATS) and British Medical Research Council (BMRC) definitions. Modified ATS had the highest sensitivity (77%), whereas BMRC had the highest specificity (99%). The most sensitive symptom was "wheeze with cold" (89%). The most specific symptoms were "medication required," and "breathing normal between attacks" (95%). Definitions and symptoms were poor predictors of BHR. Researchers can use these estimates in selecting and defining specific populations of children with asthma.
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81
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Devlin JW, Boleski G, Mlynarek M, Nerenz DR, Peterson E, Jankowski M, Horst HM, Zarowitz BJ. Motor Activity Assessment Scale: a valid and reliable sedation scale for use with mechanically ventilated patients in an adult surgical intensive care unit. Crit Care Med 1999; 27:1271-5. [PMID: 10446819 DOI: 10.1097/00003246-199907000-00008] [Citation(s) in RCA: 281] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To establish the validity and reliability of a new sedation scale, the Motor Activity Assessment Scale (MAAS). DESIGN Prospective, psychometric evaluation. SETTING Sixteen-bed surgical intensive care unit (SICU) of a 937-bed tertiary care, university-affiliated teaching hospital. PATIENTS Twenty-five randomly selected, adult, mechanically ventilated, nonneurosurgical patients who were admitted to the SICU > or = 12 hrs after surgery and were not receiving neuromuscular blockers. INTERVENTION Four hundred assessments (eight per patient) were completed consecutively but independently, in pairs, at standardized times (both day and night) by two nurses who were preselected for each assessment from a pool of 32 pretrained SICU nurses. MEASUREMENTS AND MAIN RESULTS To estimate validity, paired assessments (four/patient) compared the MAAS result with the subjective assessment using a 10-cm visual analog sedation scale, the percent change in blood pressure and heart rate from the previous 4-hr baselines, and the number of recent agitation-related sequelae. To estimate reliability, paired assessments (four/patient) measured correlation between assessments of the same type (e.g., MAAS-MAAS). Generalized estimating equations, which accounted for the four repeated measures in each patient, supported MAAS validity by finding a linear trend between MAAS and the visual analog scale (p < .001), blood pressure (p < .001), heart rate (p < .001), and agitation-related sequelae (p < .001) end points. The MAAS (kappa = 0.83 [95% confidence interval, 0.72 to 0.94]) was found to be more reliable than subjective assessment using the visual analog scale (intraclass correlation coefficient = 0.32 [95% confidence interval, 0.05 to 0.55]). CONCLUSIONS The MAAS is a valid and reliable sedation scale for use with mechanically ventilated patients in the SICU. Further studies are warranted regarding the effect of MAAS implementation in our SICU on patient outcomes, such as quality of sedation and length of mechanical ventilation, as well as the use of the MAAS in other patient populations (e.g., medical).
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Kagan J, Snidman N, Zentner M, Peterson E. Infant temperament and anxious symptoms in school age children. Dev Psychopathol 1999; 11:209-24. [PMID: 16506531 DOI: 10.1017/s0954579499002023] [Citation(s) in RCA: 186] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A group of 164 children from different infant temperament categories were seen at 7 years of age for a laboratory battery that included behavioral and physiological measurements. The major results indicated that children who had been classified as high reactive infants at 4 months of age, compared with infants classified as low reactive, (a) were more vulnerable to the development of anxious symptoms at age 7 years, (b) were more subdued in their interactions with a female examiner, (c) made fewer errors on a task requiring inhibition of a reflex, and (d) were more reflective. Further, the high reactives who developed anxious symptoms differed from the high reactives without anxious symptoms with respect to fearful behavior in the second year and, at age 7 years, higher diastolic blood pressure, a narrower facial skeleton, and greater magnitude of cooling of the temperature of the fingertips to cognitive challenge. Finally, variation in magnitude of interference to fearful or aggressive pictures on a modified Stroop procedure failed to differentiate anxious from nonanxious or high from low reactive children.
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83
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Ramanan SV, Brink PR, Varadaraj K, Peterson E, Schirrmacher K, Banach K. A three-state model for connexin37 gating kinetics. Biophys J 1999; 76:2520-9. [PMID: 10233068 PMCID: PMC1300223 DOI: 10.1016/s0006-3495(99)77406-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
The gating behavior of human connexin 37 (hCx37) is unaffected by the nature of the bathing monovalent (for Na, K, Rb). It is modified by [Mg] in the millimolar range. For fitting the kinetics, we propose a simple extension to three states of the canonical 2-state model of the hemichannel. The extra closed state allows for some immobilization of a hemichannel at high transjunctional voltages. The model is reasonably efficient at fitting data at various voltage protocols. Interpreting the fits of the data at different [Mg] is consistent with a binding site for Mg.
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84
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Higgins RSD, Khanna S, Simmonetti V, Drost C, Peterson E, Stark A, Czerska B, Philbin E, Silverman N. MALIGNANT NEOPLASMS IN CARDIAC TRANSPLANT RECIPIENTS. Transplantation 1999. [DOI: 10.1097/00007890-199904150-00423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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85
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Samali A, Nordgren H, Zhivotovsky B, Peterson E, Orrenius S. A comparative study of apoptosis and necrosis in HepG2 cells: oxidant-induced caspase inactivation leads to necrosis. Biochem Biophys Res Commun 1999; 255:6-11. [PMID: 10082646 DOI: 10.1006/bbrc.1998.0139] [Citation(s) in RCA: 147] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Apoptosis and necrosis are two distinct forms of cell death that can occur in response to various agents. In the present study the HepG2 cell line was used for a comparative study of CD95-mediated apoptosis and menadione-induced necrosis. Apoptosis coincided with the release of cytochrome c from mitochondria, activation of caspases, cleavage of cellular proteins, and also involved nuclear condensation and DNA fragmentation. Necrosis was not accompanied by DNA fragmentation, caspase activation or cleavage of caspase target proteins, despite cytochrome c release from mitochondria. In fact, the addition of menadione to cells undergoing CD95-mediated apoptosis blocked their caspase activity. Inhibition of caspases coincided with an accumulation of reactive oxygen species (ROS) and ATP depletion. In order to determine the predominance of either of these events in the inhibition of caspase, cells were either co-incubated with antioxidant enzymes or their ATP level was manipulated to maintain it at a relatively high level during the experiments. Co-incubation with catalase, but not Cu/Zn superoxide dismutase, substantially reduced the levels of ROS and reversed the inhibitory effect of menadione on caspase activity. In contrast, increasing cellular ATP level had little effect on restoring caspase activity. These data suggest that menadione inhibits caspase activity by the generation of hydrogen peroxide through redox cycling and that caspase inactivation by this mechanism may prevent cell death by apoptosis in this oxidative-stress model.
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86
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Silagyi-Rebovich J, Brooks G, Peterson E. Efficacy of an assessment instrument to measure affective and cognitive learning domains of students enrolled in food or nutrition courses. J Hum Nutr Diet 1998. [DOI: 10.1046/j.1365-277x.1998.00122.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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87
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Peterson E, Solomon D. Maintaining healthy boundaries in professional relationships: a balancing act. HOME CARE PROVIDER 1998; 3:314-8. [PMID: 10030211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
For most people, the term boundary brings to mind an image of some physical barrier that keeps something in or out, such as a fence or a wall. These examples are physical, but boundaries also can be emotional or interpersonal. Just as physical boundaries keep some things in and others out, so do emotional ones. Emotional or interpersonal boundaries are the necessary space between people that allows a sense of individuality and separateness. This sense of uniqueness is essential for the development of a healthy person and ultimately the development of a professional identity.
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88
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Higgins RS, Paone G, Borzak S, Jacobsen G, Peterson E, Silverman NA. Effect of payer status on outcomes of coronary artery bypass surgery in blacks. Circulation 1998; 98:II46-9; discussion II49-50. [PMID: 9852879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
BACKGROUND Black patients with coronary artery disease have a higher mortality rate than white Americans. They also have a higher prevalence of hypertension, diabetes mellitus, and renal disease, which may have an effect on mortality rates. The deleterious effect of these comorbidities may be exacerbated by impaired access to secondary prevention strategies and longitudinal care. Therefore, the presence or absence of comprehensive care as indicated by payer status may then affect survival on surgically treated patients. In this study we examined the role of cardiovascular risk factors and insurance carrier status on early outcomes of coronary artery bypass grafting (CABG) surgery in blacks versus white Americans. METHODS AND RESULTS From January 1990 to December 1996, 2776 patients (2003 men, 773 women; mean age 63 +/- 10 years), underwent isolated CABG in a multispecialty practice serving a major metropolitan population. There were 494 (17.8%) black patients and 2282 (82.2%) white patients. The proportion of black patients in each payer category was 17.8% commercial, 14.1% managed care, 52.9% Medicaid, and 19.5% Medicare. The effect of preoperative risk factors, including status of operation (elective, urgent, or emergent), sex, race, redo CABG, presence of renal disease, diabetes mellitus, congestive heart failure, myocardial infarction, the completeness of revascularization, age, and left ventricular ejection fraction were analyzed with the chi 2 test for categorical variables and the Student t test for age and ejection fraction. A multiple logistic regression analysis was performed to assess the effect of all variables on mortality rates simultaneously. Black patients had a higher incidence of diabetes mellitus, hypertension, and renal disease than white patients (P < 0.001). Overall, 30-day mortality rate was 2.5% (58 of 2282) in white patients versus 5.5% (25 of 494) for black patients (P < 0.003). Multivariate analysis showed that only emergency surgery status (OR 3.59, P < 0.01), redo CABG (OR 3.78, P < 0.001), hypertension (OR 2.32, P < 0.03), history of congestive heart failure (OR 2.1, P < 0.004), older age (OR 1.07, P < 0.001), and low ejection fraction (OR 0.98, P < 0.003) correlated with mortality rates. Race and payer status were not significant predictors of death. CONCLUSIONS These data on CABG surgery in black patients suggest that early death is due to associated risk factors and not due to race or insurance payer status.
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Tennstedt S, Howland J, Lachman M, Peterson E, Kasten L, Jette A. A randomized, controlled trial of a group intervention to reduce fear of falling and associated activity restriction in older adults. J Gerontol B Psychol Sci Soc Sci 1998; 53:P384-92. [PMID: 9826971 DOI: 10.1093/geronb/53b.6.p384] [Citation(s) in RCA: 298] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
A randomized, single-blind controlled trial was conducted to test the efficacy of a community-based group intervention to reduce fear of falling and associated restrictions in activity levels among older adults. A sample of 434 persons age 60+ years, who reported fear of falling and associated activity restriction, was recruited from 40 senior housing sites in the Boston metropolitan area. Data were collected at baseline, and at 6-week, 6-month, and 12-month follow-ups. Compared with contact control subjects, intervention subjects reported increased levels of intended activity (p < .05) and greater mobility control (p < .05) immediately after the intervention. Effects at 12 months included improved social function (p < .05) and mobility range (p < .05). The intervention had immediate but modest beneficial effects that diminished over time in the setting with no booster intervention.
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90
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Brink PR, Peterson E, Banach K, Walcott B. Electrophysiological evidence for reduced water flow from lacrimal gland acinar epithelium of NZB/NFW F1 mice. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1998; 438:209-19. [PMID: 9634889 DOI: 10.1007/978-1-4615-5359-5_31] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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91
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Bentinger M, Grünler J, Peterson E, Swiezewska E, Dallner G. Phosphorylation of farnesol in rat liver microsomes: properties of farnesol kinase and farnesyl phosphate kinase. Arch Biochem Biophys 1998; 353:191-8. [PMID: 9606952 DOI: 10.1006/abbi.1998.0611] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
As farnesol may serve as a nonsterol endogenous regulator of the mevalonate pathway, the possibility that a kinase specific for its phosphorylation is present in the rat liver was investigated. In the 10,000 g supernatant of rat liver, farnesyl monophosphate was synthesized in the presence of ATP. The Km value for farnesol was 2.3 microM. Various detergents inhibited the activity of the enzyme. The farnesol kinase was present in rough and in smooth I microsomes, but not in smooth II microsomes, mitochondria, peroxisomes, Golgi, or plasma membranes. The enzyme was associated with the inner, luminal surface of the vesicles. Further analyses have demonstrated that an enzymatic mechanism exists which catalyzes the phosphorylation of farnesyl-P to farnesyl-PP. Activity of the farnesyl phosphate kinase resulted in the phosphorylation of the monophosphate by CTP but not by ATP, GTP, or UTP. This enzyme is activated by low concentrations of detergents. Treatment with proteases and chemical probes indicate that this second phosphorylation reaction probably takes place on the outer, cytoplasmic surface of microsomal vesicles. These results demonstrate that rat liver microsomes contain two enzymes for the consecutive phosphorylation of farnesol to farnesyl-PP.
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93
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Peterson E. Do PTCA Mortality Outcomes Need to Be Risk-adjusted? Results From the National Cardiovascular Network (NCN). J Am Coll Cardiol 1998. [DOI: 10.1016/s0735-1097(97)84462-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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94
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Peterson E, Thompson L. Negotiation Teamwork: The Impact of Information Distribution and Accountability on Performance Depends on the Relationship among Team Members. ORGANIZATIONAL BEHAVIOR AND HUMAN DECISION PROCESSES 1997; 72:364-83. [PMID: 9606171 DOI: 10.1006/obhd.1997.2747] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We examined how the distribution of information among team members and accountability pressures affected the quality of negotiated settlements reached among teams of friends negotiating against teams of strangers. The main conclusions of the experiment may be summarized by the following findings: (1) Teams of strangers reaped a greater share of the joint profit than did teams of friends when teammates were accountable to a supervisor as opposed to negotiating strictly on their own behalf. (2) Teams of strangers also reaped a marginally greater share of the joint profit than did teams of friends when teammates possessed unique, as opposed to common, information about their own team's preferences. (3) Not surprisingly, teams of friends were more cohesive than were teams of strangers; however, teams of friends were also more concerned about maintaining their relationship than were teams of strangers. (4) Teams of friends felt least cohesive when they were accountable to a supervisor, whereas teams of strangers felt most cohesive when they were accountable. Similarly, friends indicated greater relationship concerns when having to deal with distributed information, whereas information distribution had no effect on the relationship concerns of strangers. (5) For teams of strangers, greater team cohesiveness was positively correlated with better performance. (6) Moreover, when teams of strangers felt more cohesive than their opponents, they earned more than teams of strangers who felt less cohesive. Copyright 1997 Academic Press.
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Brink PR, Cronin K, Banach K, Peterson E, Westphale EM, Seul KH, Ramanan SV, Beyer EC. Evidence for heteromeric gap junction channels formed from rat connexin43 and human connexin37. Am J Physiol Cell Physiol 1997; 273:C1386-96. [PMID: 9357785 DOI: 10.1152/ajpcell.1997.273.4.c1386] [Citation(s) in RCA: 139] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Homomeric gap junction channels are composed solely of one connexin type, whereas heterotypic forms contain two homomeric hemichannels but the six identical connexins of each are different from each other. A heteromeric gap junction channel is one that contains different connexins within either or both hemichannels. The existence of heteromeric forms has been suggested, and many cell types are known to coexpress connexins. To determine if coexpressed connexins would form heteromers, we cotransfected rat connexin43 (rCx43) and human connexin37 (hCx37) into a cell line normally devoid of any connexin expression and used dual whole cell patch clamp to compare the observed gap junction channel activity with that seen in cells transfected only with rCx43 or hCx37. We also cocultured cells transfected with hCx37 or rCx43, in which one population was tagged with a fluorescent marker to monitor heterotypic channel activity. The cotransfected cells possessed channel types unlike the homotypic forms of rCx43 or hCx37 or the heterotypic forms. In addition, the noninstantaneous transjunctional conductance-transjunctional voltage (Gj/Vj) relationship for cotransfected cell pairs showed a large range of variability that was unlike that of the homotypic or heterotypic form. The heterotypic cell pairs displayed asymmetric voltage dependence. The results from the heteromeric cell pairs are inconsistent with summed behavior of two independent homotypic populations or mixed populations of homotypic and heterotypic channels types. The Gj/Vj data imply that the connexin-to-connexin interactions are significantly altered in cotransfected cell pairs relative to the homotypic and heterotypic forms. Heteromeric channels are a population of channels whose characteristics could well impact differently from their homotypic counterparts with regard to multicellular coordinated responses.
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Lachman ME, Jette A, Tennstedt S, Howland J, Harris BA, Peterson E. A cognitive-behavioural model for promoting regular physical activity in older adults. PSYCHOL HEALTH MED 1997. [DOI: 10.1080/13548509708400583] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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97
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Peterson E, Horz F, Chang S. Modification of amino acids at shock pressures of 3.5 to 32 GPa. GEOCHIMICA ET COSMOCHIMICA ACTA 1997; 61:3937-3950. [PMID: 11541218 DOI: 10.1016/s0016-7037(97)00192-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Amino acids were subjected to shock impact over a pressure range of 3.5 to 32 GPa both within and without meteoritic mineral matrices. The extent of amino acid destruction, racemization, and conversion to secondary amino acids was examined. Abundances of parent compounds decreased by a factor of 10(3) over this pressure range. Racemization also occurred, but some residual optical activity remained in the amino acids surviving shocks up to 32 GPa. Secondary amino acids formed in the high peak pressure range; those identified were beta-alanine, glycine, alanine, gamma-aminobutyric acid, and beta-aminoisobutyric acid. At 30 GPa, the abundances of these daughter compounds exceeded those of the remaining initial amino acids. As the concomitant effects of high mechanical stress and temperature accompanying shocks cannot be separated in this work, their relative contribution to the observed transformations cannot be estimated. The survival of amino acids in shock experiments suggests that, after formation or emplacement of amino acids in carbonaceous chondrite parent bodies, these objects never experienced impact velocities greater than 5 km/s, which suffices to generate 30 GPa for typical silicate/silicate impacts. These results also provide guidelines for choosing appropriate capture media for interplanetary dust particles on Earth-orbiting platforms.
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Schirrmacher K, Ramanan SV, Cronin K, Peterson E, Brink PR. Voltage sensitivity of gap junction currents in rat osteoblast-like cells. BIOCHIMICA ET BIOPHYSICA ACTA 1997; 1327:89-96. [PMID: 9247170 DOI: 10.1016/s0005-2736(97)00048-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The dependence of macroscopic gap junctional conductance (g(j)) upon transjunctional voltage (Vj) was examined in 39 paired osteoblast-like (OB) cells from primary cultures using the double whole cell patch clamp technique. OB cells were derived from calvarial explants of new-born rats. Instantaneous current-voltage (Ij-Vj) relationships of OB cell pairs (n = 6) were linear in the entire voltage range (-150 < Vj < 150 mV) examined. The steady-state Ij-Vj relationship was non-linear for V > or = +/-60 mV. The curve for the normalised steady-state junctional conductance-voltage relationship (Gss/G0-Vj) was bell-shaped, and was fitted with a two-state Boltzmann equation with a minimum conductance (Gmin) of 0.2-0.3, and a half deactivation voltage (Vo) of +/-83 mV. In two recordings unitary gap junction channel activity was observable. The linear I-V relationships revealed a single channel conductance of approximately 100 pS. Application of parathyroid hormone (10(-8) M) had no effect on the voltage dependence nor the magnitude of macroscopic currents (n = 7).
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Zarnoth P, Sniezek JA, Dovidio JF, Gaertner SL, Validzic A, Matoka K, Johnson B, Frazier S, Mitchell TR, Thompson L, Peterson E, Cronk R. How Do Logical Inference Rules Help Construct Social Mental Models? JOURNAL OF EXPERIMENTAL SOCIAL PSYCHOLOGY 1997; 33:367-400. [PMID: 9237884 DOI: 10.1006/jesp.1997.1325] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Starting from recent approaches in mental model research, it is argued that (1) logical inference rules are used in order to construct mental cliques from learned sentiment relations, and (2) social context cues (operationalized as primes) play a crucial role in activating such rules. Transitivity and antitransitivity are taken as examples, and are shown as core constituents of such models. In a first experiment, priming was achieved by announcing the sorting of fictitious persons in either two or three cliques. Thirty-one subjects studied eight sets of sentiment relations among these persons that either did or did not satisfy their primed clique expectations. They showed longer study times and more requests for additional information in the case of inconsistent fits between prime and set. Their sorting solutions also showed clear priming effects. A second experiment (n = 30) showed that when undergoing a recognition test after seeing the relation sets, subjects tended to confuse model-consistent distractors with information they had actually seen. In a third experiment (n = 30) the results from Experiment 1 were replicated using more realistic learning materials.
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Dellinger D, Peterson E. Giving peace a push. Interview by Judith Gips. THE BIRTH GAZETTE 1997; 13:39-43. [PMID: 9250063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Lifelong peace and justice activists Dave Dellinger and Elizabeth Peterson have been inspirations to many, including myself, over the last fifty or more years. Dave's collection of essays, Revolutionary Nonviolence, spanning thirty years of committed and loving resistance to injustice in all its forms, is an illuminating glimpse into how things could be if more of us shared such willingness to examine our assumptions and our privileges. Here they tell us of birthing their five children, three at home. They have eleven grandchildren and two great-grandchildren.
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