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O'Connor D, Peterson C, Whitfield J. Telehealth. What does it offer for public health care? AUSTRALIAN FAMILY PHYSICIAN 2000; 29:403-4. [PMID: 10835774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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Michaels AJ, Michaels CE, Smith JS, Moon CH, Peterson C, Long WB. Outcome from injury: general health, work status, and satisfaction 12 months after trauma. THE JOURNAL OF TRAUMA 2000; 48:841-8; discussion 848-50. [PMID: 10823527 DOI: 10.1097/00005373-200005000-00007] [Citation(s) in RCA: 256] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE We evaluated outcomes 12 months after trauma in terms of general health, satisfaction, and work status. METHODS Two hundred forty-seven patients without severe neurotrauma were evaluated by interview during admission and by mailed self-report 6 and 12 months after trauma. Data were obtained from the Trauma Registry, interviews, and survey instruments. Baseline assessment was obtained with the Short Form 36 (SF36) and the Sickness Impact Profile (SIP) work scale. Outcome measures were the SF36, SIP work scale, Brief Symptom Inventory (BSI) depression scale, the Civilian Mississippi Scale for Posttraumatic Stress Disorder (PTSD), and a satisfaction questionnaire. Three regressions were determined for outcome. The dependent variables were general health and work status (linear) and satisfaction (logistic). Each regression controlled for baseline status and mental health, Injury Severity Score (ISS), and 12-month SF36 physical function before evaluating the effect of outcome mental health. RESULTS Follow-up data were available for 75% of the patients at 6 months and 51% at 12 months. The mean age of patients was 37.2 +/- 0.9 years (+/-SEM), and 73% were male. Their average ISS was 13.9 +/- 0.6. Seventy percent of injuries were blunt force, 13.5 % were penetrating, and 16.5 % were burn injuries (mean total body surface area, 13.3 +/- 1.5%). Sixty-four percent of the patients had returned to work at 12 months. Follow-up SF36 mental health was associated with the dependent outcome in each regression. After controlling for baseline status and mental health, ISS, and outcome SF36 physical function, outcome mental health was associated with outcome SF36 general health (p < 0.001), SIP work status (p = 0.017), and satisfaction with recovery (p = 0.005). Outcome SF36 mental health was related to baseline mental health, 12-month PTSD and BSI depression scores, and increased drug and alcohol use. CONCLUSIONS Twelve months after trauma, patients' work status, general health, and overall satisfaction with recovery are dependent on outcome mental health. This dependency persists despite measured baseline status, ISS, or physical recovery. The mental disease after trauma is attributable to poor mental health, the development of symptoms of PTSD and depression, and increased substance abuse. Trauma centers that fail to recognize, assess, and treat these injury-related mental health outcomes are not fully assisting their patients to return to optimal function.
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Abstract
The common cold has been estimated to cost the United States > $3.5 billion per year. Despite several randomized clinical trials, the effect of treating colds with zinc gluconate remains uncertain due to conflicting results. We conducted a meta-analysis of published randomized clinical trials on the use of zinc gluconate lozenges in colds using the random effects model of DerSimonians and Laird. Ten clinical trials of cold treatment with zinc gluconate were identified. After excluding two studies that used nasal inoculum of rhinovirus, eight trials were combined and analyzed. The summary odds ratio for the presence of "any cold symptoms" at 7 d was 0.52 (95% confidence interval, 0.25-1.2). We conclude that despite numerous randomized trials, the evidence for effectiveness of zinc lozenges in reducing the duration of common colds is still lacking.
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Thomas SH, Orf J, Peterson C, Wedel SK. Frequency and costs of laboratory and radiograph repetition in trauma patients undergoing interfacility transfer. Am J Emerg Med 2000; 18:156-8. [PMID: 10750920 DOI: 10.1016/s0735-6757(00)90008-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Receiving trauma centers often duplicate laboratory and radiograph testing performed by referring institutions. Our objective was to quantify frequency and costs of this practice. In this prospective study of 104 consecutive interfacility-transported adult trauma patients flown by an emergency medical service to an urban level I center, flight crew noted which labs and radiographs were done at referring hospitals, which tests were sent with patients, and which were repeated on trauma center arrival. Overall, results from 246 of 283 (86.9%) laboratory tests and 241 of 249 (96.8%) radiographs done at referring hospitals were sent with patients. Repetition of laboratory tests at the receiving hospital was frequent regardless of whether initial results were sent (P = .6 by chi2), and radiograph repetition was unrelated to whether sent films were originals or copies (P = .2 by chi2). For these 104 patients, the receiving hospital charged $66,463 for repetition of work-up done at referring facilities.
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Thilaganathan B, Sairam S, Ballard T, Peterson C, Meredith R. Effectiveness of prenatal chromosomal analysis using multicolor fluorescent in situ hybridisation. BJOG 2000; 107:262-6. [PMID: 10688511 DOI: 10.1111/j.1471-0528.2000.tb11698.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To evaluate the clinical effectiveness of multicolour fluorescent in situ hybridisation (FISH) analysis in routine prenatal diagnosis. DESIGN Prospective study. SAMPLE 3,203 amniotic fluid samples. METHODS Unique DNA (chromosomes 13 and 21) and alpha satellite centromeric-specific (chromosomes X, Y and 18) probes were used in two mixes to permit the simultaneous analysis of several chromosomes. The performance of multicolour FISH and conventional cytogenetic analysis was compared. RESULTS Conventional cytogenetic analysis identified 111 chromosomal abnormalities, of which 94 were potentially detectable by the FISH technique and 97 would be typically associated with neonatal phenotypic abnormalities. Multicolour FISH analysis detected 84% (93/111) of all chromosome abnormalities and 99% (93/94) of abnormalities where there was a specific probe. The sensitivity of multicolour FISH analysis was 95% (92/97) for chromosomal abnormalities likely to result in an abnormal postnatal outcome. Multiple ultrasound abnormalities were detected in all five cases of clinically relevant chromosomal abnormalities missed by multicolour FISH. FISH results were available within 48 hours and the sample failure rate was 0 x 1% (3/3,202). CONCLUSION Multicolour FISH analysis is a sensitive and reliable technique for the rapid prenatal diagnosis of chromosomal abnormalities. Examining only five chromosomes allowed 95% of clinically relevant chromosomal abnormalities to be diagnosed correctly. As routine antenatal screening is targeted at the major autosomal trisomies and sex chromosome aneuploidies, multicolour FISH analysis may potentially replace conventional cytogenetic analysis in routine prenatal diagnosis.
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Knaust E, Porwit-MacDonald A, Gruber A, Xu D, Peterson C. Heterogeneity of isolated mononuclear cells from patients with acute myeloid leukemia affects cellular accumulation and efflux of daunorubicin. Haematologica 2000; 85:124-32. [PMID: 10681718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
BACKGROUND AND OBJECTIVE Pharmacologic studies on blasts from patients with leukemia are generally performed on density gradient isolated blood or bone marrow cells. Thereby, cellular drug accumulation and efflux are determined as mean values of the entire cell population. The objective of the present study was to characterize the heterogeneity in the accumulation and efflux of daunorubicin in various subpopulations of mononuclear cells isolated from patients with acute myeloid leukemia (AML). DESIGN AND METHODS Mononuclear cells from 33 patients with AML were isolated from peripheral blood by density gradient centrifugation on Lymphoprep (1. 077 g/mL). Cellular accumulation of fluorescent daunorubicin was determined by flow cytometry after incubation of the cells at +37C for 1 hour. Thereafter, the cells were washed and reincubated in drug-free medium. Kinetics of drug efflux were determined by frequent determination of cellular fluorescence during 30 min. Daunorubicin accumulation and efflux were compared in the total isolated mononuclear cell population and in the various blast cell populations gated on FSC/SSC according to the results of immunophenotyping. RESULTS In 8 of these 33 (24%) patient samples, two distinct blast cell populations could be identified. In 7 out of 8 these cases the more immature blasts had a lower drug accumulation and in 6 out of the 8 cases also a higher efflux rate than the differentiating cell population. Cyclosporin A increased daunorubicin accumulation and reduced efflux in the immature blast population. In the differentiating cell population cyclosporin A increased both the accumulation and the efflux. In patients with a single blast cell population, the gated blast cells had a significantly lower drug accumulation but also a lower drug efflux rate than the total cell population. INTERPRETATION AND CONCLUSIONS The results imply that drug transport studies on cells isolated from patients with AML give somewhat different results depending on the cell population studied. Some, but not all, of these differences in daunorubicin accumulation and efflux as well as in the effect of cyclo-sporin A can be explained by a heterogenous expression of the mdr1-gene. The observed heterogeneity may be of special relevance with regard to drug resistance. The presence of even a small resistant cell clone may jeopardize the effect of the chemotherapy due to expansion resulting in relapse of disease.
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Peterson C, Kordich J, Milligan L, Bodor E, Siner A, Nagy K, Paquin CE. Mutations in RAD3, MSH2, and RAD52 affect the rate of gene amplification in the yeast Saccharomyces cerevisiae. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2000; 36:325-334. [PMID: 11152565 DOI: 10.1002/1098-2280(2000)36:4<325::aid-em8>3.0.co;2-b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We report here the use of the ADH4:CUP1 amplification detection system to identify five high amplification rate (HAR) strains of Saccharomyces cerevisiae that display 40- to 600-fold higher amplification rates than those of parental strains. We have identified a mutation in RAD3 DNA repair helicase gene in HAR strain B9-40 that results in a 40-fold increase in amplification rate. RAD3 is the functional homolog of the human XPD gene, suggesting that this model system will provide important candidates for genes that affect gene amplification in human cells. Isolation of the HAR strains has allowed us to test whether RAD52, which is essential for recombinational repair of DNA double-strand breaks, is also essential for amplification. Deletion of RAD52 in HAR strains B3-10 and B11-60 decreases amplification approximately 100-fold. In contrast, deletion of MSH2, which increases recombination between sequences with limited similarity, increases the amplification rate about 10-fold. These results suggest that recombination is an important step in amplification.
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Abstract
Recent theoretical discussions of optimism as an inherent aspect of human nature converge with empirical investigations of optimism as an individual difference to show that optimism can be a highly beneficial psychological characteristic linked to good mood, perseverance, achievement, and physical health. Questions remain about optimism as a research topic and more generally as a societal value. Is the meaning of optimism richer than its current conceptualization in cognitive terms? Are optimism and pessimism mutually exclusive? What is the relationship between optimism and reality, and what are the costs of optimistic beliefs that prove to be wrong? How can optimism be cultivated? How does optimism play itself out across different cultures? Optimism promises to be one of the important topics of interest to positive social science, as long as it is approached in an even-handed way.
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Peterson C. Nursing international. Am J Nurs 2000; 100:65-6. [PMID: 10705842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
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Halldén G, Nopp A, Ihre E, Peterson C, Lundahl J. Conditions in blood sampling procedures that extend the ex vivo stability of eosinophil activity markers in peripheral blood from allergic patients and healthy controls. Ann Allergy Asthma Immunol 1999; 83:413-21. [PMID: 10582722 DOI: 10.1016/s1081-1206(10)62839-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Serum-ECP, EG2-epitope on intracellular ECP and surface expression of CD9 and CD11b in peripheral blood eosinophils (PBE) are considered to be markers that mirror clinical parameters in allergic inflammation. OBJECTIVE The aim was to investigate the impact of the blood sampling procedure on PBE markers and to identify optimal conditions for extended pre-analysis storage. METHODS Blood, from healthy individuals and patients with allergic rhinitis/asthma, was collected in tubes with EDTA, citrate, or without anti-coagulant. The expression of EG2-epitope, CD9, and CD11b were analyzed in eosinophils and neutrophils after 1, 5, and 24 hours of storage at +4 degrees C, according to the FOG-method and flow cytometry. In vitro stimulation with fMLP/PMA was used for metabolic activity analysis and CD11b mobilization. Following a 1-hour clotting period at +20 to 22 degrees C, samples were stored at +4 degrees C and serum-ECP levels were measured. RESULTS The EG2-epitope, serum-ECP, and CD9 were stable in samples from both healthy controls and allergic patients at all storage conditions. The EG2-epitope, serum-ECP and PBE count were significantly increased in the patient group, whereas no differences were observed in the expression of CD9 or CD11b. Both granulocytes and monocytes retained their metabolic activity for 24 hours. Neutrophils in citrate-blood increased their ability to respond to fMLP, as compared with EDTA-blood. CONCLUSION In vitro analysis of selected activity markers and functional tests could be performed on granulocytes from both healthy individuals and allergic patients after 24 hours storage at +4 degrees C. The anticoagulant citrate seems to be preferable to EDTA when monocytes or CD11b expression are analyzed.
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Peterson C. Linked for better health. HEALTHPLAN 1999; 40:48-53. [PMID: 11067350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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137
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Abstract
Long-term recall of medical emergencies (including both injury and hospital treatment) by 2- to 13-year-olds was assessed 2 years after injury. Event identity was important: Children recalled injury details better than hospital treatment. Ninety-six children were interviewed 3 times prior to the 2-year recall; amount recalled decreased only for hospital treatment details, although accuracy of recall decreased for both injury and treatment. Twenty-one children were interviewed only twice prior to the 2-year interview. An extra interview 1 year after their injury had little effect on how much older children recalled about both injury and treatment or how much younger children recalled about injury details, but it helped younger children recall the less memorable hospital event. The extra interview also helped all children maintain accuracy when recalling hospital details but was unnecessary for the more memorable injury event. Implications for children's testimony are discussed.
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Michaels AJ, Michaels CE, Zimmerman MA, Smith JS, Moon CH, Peterson C. Posttraumatic stress disorder in injured adults: etiology by path analysis. THE JOURNAL OF TRAUMA 1999; 47:867-73. [PMID: 10568714 DOI: 10.1097/00005373-199911000-00009] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Posttraumatic Stress Disorder (PTSD) impairs outcome from injury. We present a path analysis of factors related to the development of PTSD in injured adults. METHODS A prospective cohort of 250 patients without severe neurotrauma was evaluated by interview during admission and by mailed self-report 6 months later. Data were gathered from the trauma registry (age, injury mechanism, and Injury Severity Score), social history (gender, income, education, and social support), and survey instruments. Baseline assessment used the Michigan Critical Events Perception Scale (peritraumatic dissociation and subjective threat to life), the Life Experience Survey (stressful exposure history), and the SF36 (general and mental health). PTSD at 6 months was identified with the civilian Mississippi Scale for PTSD. Data are listed as mean +/- SEM or percent (%). Path analysis was conducted by linear regression and significant (p<0.05) variables are shown. Factors are listed with the standardized beta. A negative beta suggests a protective effect. RESULTS The 176 patients (72%) who completed the 6-month follow-up were 37.7+/-0.88 years old; 75% were men; and blunt (70%), penetrating (13.5%), and burn (16.4%) mechanisms caused the injuries. Assault was involved in 14.5% of the cases. Average income was $44,300+/-2,700/yr, education was 13.0+/-0.15 years, and Injury Severity Score was 13.9+/-0.50. A total of 42.3% of the patients developed PTSD. The 39.7% of the variance in PTSD explained by the model was due to intentional injury (beta = 0.27), male gender (beta = -0.21), age (beta = -0.20), peritraumatic dissociation (beta = 0.174), baseline mental health (beta = -0.21), and prior life-threatening illness (beta = -0.29). Peritraumatic dissociation was due to the patient's sense of threat to life (beta = -0.47), and threat was related to Injury Severity Score (beta = 0.2), assault(beta = 0.14), education (beta = -0.15), and age (beta = -0.19). Baseline SF36 mental health was related to social support (beta = 0.27) and income (beta = 0.21). Income was contingent on education (beta = 0.21). CONCLUSION PTSD occurred in 42.3% of injured adults 6 months after trauma and was related to assault, dissociation, female gender, youth, poor mental health, and prior illness. By modeling PTSD, we may learn more of the etiology, risk stratification, and potentials for the treatment of this common and important morbidity of injury.
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Peterson C, Dowden C, Tobin J. Interviewing preschoolers: comparisons of yes/no and wh- questions. LAW AND HUMAN BEHAVIOR 1999; 23:539-55. [PMID: 10487148 DOI: 10.1023/a:1022396112719] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
This study investigated the influence of question format on preschool-aged children's errors, their response accuracy, and their tendency to say "I don't know" when given non-misleading questions in a neutral, unbiased context. Children (3 to 5 years old) participated in a craft-making session that included a staged "accident" with two experimenters differing in gender and appearance; the environment also had several distinctive features. One week later children were interviewed about actions, participants, and environment; questions were yes/no format with the veridical response "yes" ("yes" questions), yes/no format with the veridical response "no" ("no" questions), and specific wh- format questions. Question format substantially influenced children's responses: they were most likely to make errors if asked "no" questions, and were unlikely to answer either yes/no question with "I don't know." In contrast, children spontaneously and frequently said "I don't know" to wh- questions about content they did not recall (environment), but not about content that was well recalled (actions). Implications of question format for reliability of eyewitness testimony by preschoolers are discussed.
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Lönnerholm G, Frost BM, Larsson R, Liliemark E, Nygren P, Peterson C. In vitro cytotoxic drug activity and in vivo pharmacokinetics in childhood acute myeloid leukemia. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1999; 457:429-35. [PMID: 10500819 DOI: 10.1007/978-1-4615-4811-9_46] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Since May 1996 all Nordic countries have been participating in a study of childhood acute myeloid leukemia (AML). The aim is to correlate the in vitro sensitivity of leukemic cells and individual plasma concentrations of cytotoxic drugs with clinical effect. Blast cells from bone marrow and/or peripheral blood are tested against a panel of cytotoxic agents using the fluorometric microculture cytotoxicity assay (FMCA). Plasma concentrations of cytotoxic drugs are analysed during induction therapy. Bone marrow samples from the participating centres generally reached the analysing laboratory within 24 hours. 61 out of 71 (86%) samples were successfully analysed, 47 de novo AML and 14 relapses. Relapsing patients tended to have a more resistant test profile than newly diagnosed patients. Steady state plasma levels of doxorubicin, etoposide and 6-thioguanine nucleotide varied about 10-fold between patients. The intra-individual variation was much less, suggesting that dose adjustment based on pharmacokinetic data might be useful in the future.
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Xu D, Areström I, Virtala R, Pisa P, Peterson C, Gruber A. High levels of lung resistance related protein mRNA in leukaemic cells from patients with acute myelogenous leukaemia are associated with inferior response to chemotherapy and prior treatment with mitoxantrone. Br J Haematol 1999; 106:627-33. [PMID: 10468850 DOI: 10.1046/j.1365-2141.1999.01611.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Expression of the mdr1 (multidrug resistance), mrp (multidrug resistance associated protein), and lrp (lung resistance related protein) genes is associated with transport related MDR (multidrug resistance). We quantified mRNA levels of these genes using competitive reverse transcription polymerase chain reaction (RT-PCR) in 128 samples of leukaemic cells from 92 patients with acute myelogenous leukaemia (AML). There was a wide variation between the samples in mRNA levels of all three genes. The mean mdr1 mRNA level was 1.3 transcripts per cell (range undetectable to 15.8), the mean mrp level was 7.9 (range 0.1-36.2) and mean lrp 3.9 (range 0.1-29). Lrp mRNA levels were higher in samples drawn at diagnosis from the 15 patients with resistant disease than from the 37 with chemosensitive disease (4.9 SD 3.1 v 2.9 SD 2.3, P = 0.016). Neither mdr1 nor mrp mRNA levels were predictive for response to chemotherapy. In samples from patients who had received chemotherapy, those that had received mitoxantrone (n = 24) had higher lrp mRNA levels (mean 4.8, SD 2.5) than those that had not (n = 20, mean 2.8, SD 2.4, P = 0.012). In conclusion, the results indicate that lrp expression is associated with inferior response to chemotherapy in AML and that lrp expression increases after exposure to mitoxantrone.
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Venge P, Byström J, Carlson M, Hâkansson L, Karawacjzyk M, Peterson C, Sevéus L, Trulson A. Eosinophil cationic protein (ECP): molecular and biological properties and the use of ECP as a marker of eosinophil activation in disease. Clin Exp Allergy 1999; 29:1172-86. [PMID: 10469025 DOI: 10.1046/j.1365-2222.1999.00542.x] [Citation(s) in RCA: 217] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Lotfi K, Månsson E, Spasokoukotskaja T, Pettersson B, Liliemark J, Peterson C, Eriksson S, Albertioni F. Biochemical pharmacology and resistance to 2-chloro-2'-arabino-fluoro-2'-deoxyadenosine, a novel analogue of cladribine in human leukemic cells. Clin Cancer Res 1999; 5:2438-44. [PMID: 10499616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
The objective of the present study was to investigate the biochemical pharmacology of 2-chloro-2'-arabino-fluoro-2'-deoxyadenosine (CAFdA)--a fluorinated analogue of cladribine [2-chloro-2'-deoxyadenosine, Leustatin (CdA)] with improved acid and metabolic stability--in human leukemic cell lines and in mononuclear cells isolated from patients with chronic lymphocytic leukemia (CLL) and acute myelocytic leukemia (AML). We have also made and characterized two cell lines that are not sensitive to the growth inhibitory and cytotoxic effects of CAFdA. Incubation of cells isolated from the blood of CLL and AML patients with various concentrations of CdA or of CAFdA accumulated CdA and CAFdA nucleotides in a dose-dependent manner. A significantly higher rate of phosphorylation to monophosphates was observed for CAFdA than for CdA in cells from CLL patients (n = 14; P = 0.04). The differences in the phosphorylation were even more pronounced for the respective triphosphates in both CLL (n = 14; P = 0.001) and AML (n = 4; P = 0.04) cells. Retention of CAFdA 5'-triphosphate (CAFdATP) was also longer than that for CdA 5'-triphosphate (CdATP) in cells from leukemic patients. The relative efficacy of CAFdA as a substrate for purified recombinant deoxycytidine kinase (dCK), the key enzyme in the activation of nucleoside analogues, was very high and exceeded that of CdA as well as the natural substrate, deoxycytidine, by a factor of 2 and 8, respectively. The Km for CAFdA with dCK was also lower than that for CdA, as measured in crude extracts from the human acute lymphoblastic leukemia cell line CCRF-CEM and the promyelocytic leukemia cell line HL60. Acquired resistance to CAFdA in HL60 and in CCRF-CEM cell lines was directly correlated to the decreased activity of the nucleoside phosphorylating enzyme, dCK. Resistant cells also showed a considerable degree of cross-resistance to analogues that were activated by dCK. These observations demonstrated that dCK phosphorylates CAFdA more efficiently than CdA. Furthermore, CAFdATP is apparently more stable than CdATP and the mechanisms of resistance to CAFdA are similar to those leading to CdA resistance. These results encourage studies on the clinical effect of CAFdA in lymphoproliferative diseases.
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MESH Headings
- Adenine Nucleotides
- Antineoplastic Agents/pharmacokinetics
- Antineoplastic Agents/pharmacology
- Arabinonucleosides/pharmacology
- Cladribine/metabolism
- Cladribine/pharmacokinetics
- Cladribine/pharmacology
- Clofarabine
- Deoxycytidine Kinase/metabolism
- Drug Resistance, Neoplasm
- Drug Screening Assays, Antitumor
- HL-60 Cells
- Humans
- Leukemia/drug therapy
- Leukemia/enzymology
- Leukemia/metabolism
- Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy
- Leukemia, Myeloid, Acute/drug therapy
- Leukemia, T-Cell/drug therapy
- Leukemia, T-Cell/enzymology
- Leukemia, T-Cell/metabolism
- Phosphorylation
- Recombinant Proteins/metabolism
- Tumor Cells, Cultured
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Buchholz U, Moolenaar R, Peterson C, Mascola L. Varicella outbreaks after vaccine licensure: should they make you chicken? Pediatrics 1999; 104:561-3. [PMID: 10469786 DOI: 10.1542/peds.104.3.561] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
In 1998, 3 years after vaccine licensure, child care centers (CCC) in Los Angeles County continued to report varicella outbreaks. We investigated outbreaks at 2 CCCs to determine the cause for them, such as low vaccination coverage levels or unexpected low vaccine effectiveness. We collected information on past history of varicella, illness during the outbreak, and prior varicella vaccination among CCC attendees. We found that CCC "H" had a vaccination coverage of 87% (34/39) compared with 30% (6/20) in CCC "L." The overall attack rate was lower in CCC "H" (31%) than in "L" (61%; P value =.03). Vaccine effectiveness for any varicella was 71% in "H" and 100% in "L." Vaccinated children with varicella had milder disease than unvaccinated. In conclusion, we found varicella outbreaks in CCCs with both high and low vaccination coverage. Vaccine effectiveness was within the range predicted by the literature. Vaccination led to a lower attack rate in the highly vaccinated CCC and appeared to protect from severe disease.
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Michaels AJ, Michaels CE, Moon CH, Smith JS, Zimmerman MA, Taheri PA, Peterson C. Posttraumatic stress disorder after injury: impact on general health outcome and early risk assessment. THE JOURNAL OF TRAUMA 1999; 47:460-6; discussion 466-7. [PMID: 10498298 DOI: 10.1097/00005373-199909000-00005] [Citation(s) in RCA: 145] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To evaluate prospectively components of general health outcome after trauma and to report on the further validation of the Michigan Critical Events Perception Scale (MCEPS), an instrument that predicts increased risk for posttraumatic stress disorder (PTSD). METHODS Adults without neurologic injury admitted to a Level I trauma center in 1997 were interviewed during hospitalization. Baseline data included demographics, injury mechanism, Injury Severity Score, the Short Form 36 (SF36), and the MCEPS, which measures peri-traumatic dissociation (the sense of depersonalization or derealization during an injury event). Surveys sent by mail and completed 6 months later included the SF36 and civilian Mississippi Scale for PTSD. RESULTS A total of 140 patients were interviewed; the 70% (n = 100 patients) who completed the 6-month assessment form the study group. Injuries were categorized as 71% blunt, 13% penetrating, and 16% burn. Mean Injury Severity Score was 13.7+/-0.52. PTSD at 6 months occurred in 42% of the patients and was directly related to MCEPS dissociation (p = 0.001; odds ratio = 3.1; 95% confidence interval, 1.6, 5.9). A stepwise linear regression explains 40% of the variance in 6-month SF36 general health outcome (adjusted R2 = 0.402). The model controls for individual factors related to dissociation, PTSD, and general health outcome. Development of PTSD was independently and inversely related to general health outcome as measured by the SF36 at 6 months (p < 0.001, beta = -0.404). The R2 change of 0.132 for PTSD (vs. 0.082 for 6-month physical function) illustrates that PTSD contributes more to the patient's perceived general health at 6 months than the degree of physical function or injury severity. CONCLUSIONS Within hours of injury, the MCEPS identifies patients who are three times more likely to develop PTSD. PTSD compromises self-reported general health outcome in injured adults independent of baseline status, Injury Severity Score, or degree of physical recovery. These data suggest that psychological morbidity is an important part of the patient's perceived general health.
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Holst H, Ohlsson M, Peterson C, Edenbrandt L. A confident decision support system for interpreting electrocardiograms. CLINICAL PHYSIOLOGY (OXFORD, ENGLAND) 1999; 19:410-8. [PMID: 10516892 DOI: 10.1046/j.1365-2281.1999.00195.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Computer-aided interpretation of electrocardiograms (ECGs) is widespread but many physicians hesitate to rely on the computer, because the advice is presented without information about the confidence of the advice. The purpose of this work was to develop a method to validate the advice of a computer by estimating the error of an artificial neural network output. A total of 1249 ECGs, recorded with computerized electrocardiographs, on patients who had undergone diagnostic cardiac catheterization were studied. The material consisted of two groups, 414 patients with and 835 without anterior myocardial infarction. The material was randomly divided into three data sets. The first set was used to train an artificial neural network for the diagnosis of anterior infarction. The second data set was used to calculate the error of the network outputs. The last data set was used to test the network performance and to estimate the error of the network outputs. The performance of the neural network, measured as the area under the receiver operating characteristic (ROC) curve, was 0.887 (0.845-0.922). The 25% test ECGs with the lowest error estimates had an area under the ROC curve as high as 0.995 (0.982-1.000), i.e. almost all of these ECGs were correctly classified. Neural networks can therefore be trained to diagnose myocardial infarction and to signal when the advice is given with great confidence or when it should be considered more carefully. This method increases the possibility that artificial neural networks will be accepted as reliable decision support systems in clinical practice.
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147
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Carlson M, Raab Y, Peterson C, Hällgren R, Venge P. Increased intraluminal release of eosinophil granule proteins EPO, ECP, EPX, and cytokines in ulcerative colitis and proctitis in segmental perfusion. Am J Gastroenterol 1999; 94:1876-83. [PMID: 10406252 DOI: 10.1111/j.1572-0241.1999.01223.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE The role of the eosinophil granulocyte in bowel mucosa in inflammatory bowel disease still remains obscure. The present study was performed in order to elucidate the local eosinophil activity and activating cytokines in the inflamed lesions of colon and rectum in patients with ulcerative colitis and proctitis. METHODS The activity of intestinal eosinophils with respect to the release of granule proteins was studied in 18 patients (10 with colitis and 8 with isolated proctitis) and 18 healthy controls, using intraluminal segmental perfusion of the sigmoid colon and rectum. The released amounts of eosinophil granule proteins: eosinophil cationic protein (ECP), eosinophil peroxidase (EPO), and eosinophil protein X (EPX) to perfusion fluid were determined by radioimmunoassays. The intraluminal release of possible eosinophil priming cytokines granulocyte/macrophage-colony stimulating factor (GM-CSF) and interleukin 8 (IL-8), were analyzed by immunoassays. RESULTS The mucosal release of ECP, EPO, and EPX was increased 10- to 20-fold in patients with colitis and proctitis compared with controls. The intraluminal release of GM-CSF and IL-8, was several-fold enhanced in patients with colitis and proctitis. We also found a correlation between all three eosinophil granule proteins and the levels of IL-8/GM-CSF in the sigmoidal segments of patients with colitis. CONCLUSIONS We conclude that the increased release of ECP, EPO, and EPX to colorectal perfusion fluid indicate eosinophil involvement in the local disease in patients with colitis and proctitis. IL-8 and GM-CSF may play a role in eosinophil accumulation and priming in colitis.
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148
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Piacentini GL, Peterson C, Peroni DG, Bodini A, Boner AL. Allergen avoidance at high altitude and urinary eosinophil protein X. J Allergy Clin Immunol 1999; 104:243-4. [PMID: 10400871 DOI: 10.1016/s0091-6749(99)70145-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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149
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Xu D, Gruber A, Björkholm M, Peterson C, Pisa P. Suppression of telomerase reverse transcriptase (hTERT) expression in differentiated HL-60 cells: regulatory mechanisms. Br J Cancer 1999; 80:1156-61. [PMID: 10376966 PMCID: PMC2362380 DOI: 10.1038/sj.bjc.6690480] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Telomerase activity, associated with cellular immortalization and tumorigenesis, is suppressed during terminal differentiation of HL-60 promyelocytic leukaemic cells. However, it is poorly understood how telomerase activity is regulated in differentiated HL-60 cells. In the present study, we demonstrate that the down-regulation of telomerase reverse transcriptase (hTERT) expression, the catalytic subunit, occurs prior to the suppression of telomerase activity in differentiated HL-60 cells. In contrast, the expression of telomerase RNA template (hTR) and telomerase associated protein (TP1) is not reduced. This down-regulation of hTERT expression is achieved through inhibition of gene transcription, in which process new protein synthesis is required. Moreover, the rapid down-regulation of hTERT expression followed by the inhibition of telomerase activity is a specific component of the differentiation programme and not simply a consequence of cell cycle arrest. Serum-deprivation of HL-60 cells causes cell cycle arrest without differentiation and this does not result in a significant reduction in hTERT mRNA levels within the first 24 h. Our findings suggest that hTERT expression is stringently controlled at transcriptional level in HL-60 cells. The downregulation of hTERT expression in the HL-60 cell differentiation model may represent a general regulatory mechanism through which telomerase becomes repressed during development and differentiation of human somatic cells.
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150
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Heilborn JD, Ståhle-Bäckdahl M, Albertioni F, Vassilaki I, Peterson C, Stephansson E. Low-dose oral pulse methotrexate as monotherapy in elderly patients with bullous pemphigoid. J Am Acad Dermatol 1999; 40:741-9. [PMID: 10321603 DOI: 10.1016/s0190-9622(99)70156-8] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Prednisone alone or in combination with an immunosuppressive drug is usually effective in controlling bullous pemphigoid. However, corticosteroids often cause potentially hazardous side effects, especially in elderly patients. OBJECTIVE Our purpose was to evaluate low-dose treatment with methotrexate in elderly patients with generalized bullous pemphigoid. METHODS Oral methotrexate, at an initial dosage of 5 mg/wk, was given to 11 consecutive patients older than 70 years of age who were not responding to potent topical steroids. If the response was insufficient, the methotrexate dose was increased by 2.5 mg/wk to a maximum of 12.5 mg/wk. RESULTS All patients responded with a marked and rapid decrease in disease activity. The disease was controlled in the majority of patients (8 of 11) with 5 to 7.5 mg of methotrexate per week. Three patients required a weekly dose of 10 to 12.5 mg. At 24 months of follow-up 7 patients were in complete remission and did not require methotrexate. CONCLUSION Our study suggests that low-dose oral pulse methotrexate constitutes an effective therapeutic alternative in elderly patients with generalized bullous pemphigoid.
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