726
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Abstract
The original 11 factors reported for the 29-item Depression Coping Questionnaire (DCQ) unnecessarily limits its potential usefulness as a clinically interpretable self-report measure. Therefore, the goal of this study was to reduce the number of DCQ factors to equal the number of core dimensions of depression coping addressed by the measure. Study participants (N = 668) completed the original 29-item DCQ and the Center for Epidemiological Studies-Depression (CES-D) scale. The total sample was then split into two equal randomized subsamples. Using a factor loading value cutoff of .40, an initial LISREL exploratory factor analysis produced a 22-item, three-dimension model of positive (10 items), negative (8 items), and substance/sexual (4 items) depression coping behaviors. Because both the negative and substance/sexual dimensions addressed detrimental dimensions of depression coping, these factors were intercorrelated, however, the negative dimension accounted for greater variance. Consequently, given the stated goal of this study the model was then restricted to two core dimensions of positive and negative depression coping. Using the second split-half subsample, a LISREL confirmatory factor analysis produced a 17-item, two-factor model. One negative item (daydreaming) failed to maintain a loading value of .40 or higher and was deleted. The Goodness-of-Fit index for the 17-item, two-factor DCQ was .87 and the Root Mean Square Residual was .08. DCQ alpha coefficients were acceptable at .82 (positive) and .74 (negative). Significant CES-D subgroup differences and correlations were observed.
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727
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Means LJ, Ferrari L, Mancuso TJ, Davidson P, Hackel A, Deshpande JK, Davis P, Brown R, Bailey A, Coté C. The pediatric sedation unit: a mechanism for safe pediatric sedation. Pediatrics 1999; 103:199-201. [PMID: 9988635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
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728
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Primhak RA, Smith CM, Yong SC, Wach R, Kurian M, Brown R, Efthimiou J. The bronchoprotective effect of inhaled salmeterol in preschool children: a dose-ranging study. Eur Respir J 1999; 13:78-81. [PMID: 10836327 DOI: 10.1183/09031936.99.13107899] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The optimal dose of salmeterol in infants and preschool children is not known. The aim of this study was to assess the bronchoprotective effect of different doses of salmeterol using methacholine-induced wheeze in children aged <4 yrs. Children <4 yrs old with a history of recurrent wheeze underwent two methacholine challenges within 7 days. One hour before each challenge they were pretreated in double-blind fashion using a metered-dose inhaler and Babyhaler spacer. Placebo was given before one challenge, and either 25, 50 or 100 microg of salmeterol before the other. Both the dose and treatment order were random. The provocative concentration of methacholine causing wheeze (PCwheeze) was measured on each occasion. Studies were terminated when wheeze occurred or arterial oxygen saturation (Sa,o2) fell below 91%. Of the 42 children enrolled, 33 completed the study. Two subjects refused the challenge test, two failed to return and five developed upper respiratory tract infections or wheeze between the two tests. The mean (range) age of the population was 27 (8-46) months. Ratios of PCwheeze between treatment and placebo challenges were calculated for each dosage group. The treatment/placebo ratios (95% confidence intervals) were 1.2 (0.6-2.4) for 25 microg, 2.5 (1.4-4.6) for 50 microg (p<0.01), and 4.0 (2.1-7.4) (p<0.001) for 100 microg doses. In recurrently wheezy children aged <4 yrs a single dose of salmeterol between 25 and 100 microg has a dose-dependent effect on methacholine-induced wheeze, and this is significantly different from placebo at 50 and 100 microg. This study suggests that the Babyhaler effectively delivers salmeterol to children <4 yrs of age and that doses between 50-100 microg are efficacious.
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729
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Shingleton BJ, Crandall A, Johnstone M, Robin A, Brown R. Medical treatment patterns of ASCRS members for primary open-angle glaucoma--1998 survey. J Cataract Refract Surg 1999; 25:118-27. [PMID: 9888087 DOI: 10.1016/s0886-3350(99)80021-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
A survey of medical treatment patterns for primary open-angle glaucoma (POAG) was mailed to all United States members of the American Society of Cataract and Refractive Surgery (ASCRS) in March 1998; 21.2% responded. Demographic information pertinent to glaucoma care was also obtained. The use of diagnostic ancillary tests, as well as the sequential order of preferred therapy, in 3 hypothetical patient populations was analyzed: patients with mild, moderate, and advanced POAG. Preferred medical therapy was cross-tabulated with number of years in practice, fellowship training in glaucoma, and geographic location.
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730
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Bonnier B, Brown R, Pommiers E. Self-organization in the static pair annihilation process. ACTA ACUST UNITED AC 1999. [DOI: 10.1088/0305-4470/28/18/008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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731
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Wright PM, Brown R, Lau M, Fisher DM. A pharmacodynamic explanation for the rapid onset/offset of rapacuronium bromide. Anesthesiology 1999; 90:16-23. [PMID: 9915308 DOI: 10.1097/00000542-199901000-00005] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Nondepolarizing muscle relaxants differ in their time course at the laryngeal adductors and the adductor pollicis, a result of differences in equilibration delays between plasma and effect sites, the sensitivity of each muscle to the relaxant, and the steepness of the concentration-effect relation at each muscle (the Hill factor). To determine whether similar differences exist for rapacuronium, a muscle relaxant with rapid onset and offset, the authors determined its pharmacodynamic characteristics. METHODS The twitch tensions of the adductor pollicis and the laryngeal adductors (via a tracheal tube cuff positioned at the vocal cords) were measured in 10 volunteers who were anesthetized with propofoL Rapacuronium, 1.5 mg/kg, was given and blood samples were collected. A semiparametric effect compartment pharmacodynamic model was fit to values for rapacuronium plasma concentrations and twitch tension of the adductor pollicis and laryngeal adductors. RESULTS Equilibration between the rapacuronium plasma concentration and both effect sites was rapid (typical values for the rate constant for equilibration between plasma and the effect site are 0.405 per min for the adductor pollicis and 0.630 per min for the laryngeal adductors) and was more rapid at the laryngeal adductors than at the adductor pollicis (ratio, 1.59+/-0.16; mean +/- SD). The steady state rapacuronium plasma concentration that depressed twitch tension by 50% and the Hill factor were similar for the two muscles. CONCLUSIONS The rapid onset and offset of rapacuronium can be explained by the rapid equilibration between concentrations in plasma and at the effect site. Unlike the finding for other nondepolarizing muscle relaxants, the laryngeal muscles are not resistant to rapacuronium.
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732
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Schrag A, Ben-Shlomo Y, Brown R, Marsden CD, Quinn N. Young-onset Parkinson's disease revisited--clinical features, natural history, and mortality. Mov Disord 1998; 13:885-94. [PMID: 9827611 DOI: 10.1002/mds.870130605] [Citation(s) in RCA: 225] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The authors report on clinical features and mortality rates in a group of 149 patients with apparent idiopathic parkinsonism starting before the age of 40 years. Ten had juvenile parkinsonism (JP; onset before age 21 years) and 139 had young-onset Parkinson's disease (YOPD; onset at age 21 to 40 years). Included were 60 patients originally reported 10 years ago. Fifty percent of the JP group had a positive family history of parkinsonism in a first-degree relative, and clinical presentation was heterogeneous. Mortality risk was threefold that of the normal population. In the YOPD group, the mortality risk was double that of the normal population. Poor initial response to L-dopa was a risk factor for early death. In two previously reported patients, the diagnosis had been changed to multiple system atrophy and Machado-Joseph disease. After a median disease duration of 18 years, cognitive impairment was found in only 19% of YOPD patients (13% of those younger than 60 years and 43% of those 60 years or older). Age was the most important factor for development of dementia, but female sex and positive family history of parkinsonism also had more modest predictive value. After a disease duration of 10 years or less, only 5% of patients were experiencing falls and 30% freezing, but all patients had developed L-dopa-related fluctuations and dyskinesias. The authors conclude that the mortality rate in parkinsonism starting before the age of 40 is increased in comparison to the normal population and is similar to the general Parkinson's disease population. Intellectual function and postural reflexes are usually well preserved for many years despite a long history of parkinsonism and the early and frequent occurrence of treatment complications, provided the patients remain biologically and chronologically young.
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733
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Brown R, Di Luzio L, Gomes C, Nicolaides KH. The umbilical artery pulsatility index in the first trimester: is there an association with increased nuchal translucency or chromosomal abnormality? ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 1998; 12:244-247. [PMID: 9819854 DOI: 10.1046/j.1469-0705.1998.12040244.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
OBJECTIVE The aim of this study was to examine the possible association between umbilical artery pulsatility index (PI) at 10-14 weeks of gestation and either increased fetal nuchal translucency (NT) or fetal chromosomal abnormality. DESIGN This was a prospective study of women undergoing chorionic villus sampling (CVS). SUBJECTS A total of 458 women undergoing CVS were studied; in 418 cases the karyotype was normal and in 19 cases fetal trisomy 21 was identified. METHODS Data from the women with a normal fetal karyotype and in whom the NT was also normal were used to calculate reference anges for the umbilical artery PI. Associations were sought between umbilical artery PI and increased NT and between the PI and fetal trisomy 21. RESULTS We found no association between umbilical artery PI and NT, nor was there a difference in the PI between chromosomally normal pregnancies and those with fetal trisomy 21. CONCLUSION The results suggest that fetoplacental vascular resistance per se does not contribute to increased NT and that measurement of the umbilical artery PI does not contribute to the first-trimester detection of fetal trisomy 21.
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734
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Brown R, Taylor FC, Cohen H, Ramsey M, Miller DL, Gaminara L. Setting up a nurse-led anticoagulant clinic. PROFESSIONAL NURSE (LONDON, ENGLAND) 1998; 14:21-3. [PMID: 9866613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
People on anticoagulation therapy need regular monitoring. With appropriate training, nurse specialists can improve patient care in anticoagulant clinics.
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735
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Kissinger P, Brown R, Reed K, Salifou J, Drake A, Farley TA, Martin DH. Effectiveness of patient delivered partner medication for preventing recurrent Chlamydia trachomatis. Sex Transm Infect 1998; 74:331-3. [PMID: 10195027 PMCID: PMC1758141 DOI: 10.1136/sti.74.5.331] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
OBJECTIVE To determine if providing Chlamydia trachomatis infected women with medication to deliver to their sex partner(s) could reduce recurrent chlamydia infections compared with the standard partner referral method. STUDY DESIGN A observational cohort study of 178 women, 14-39 years old attending a family planning clinic, diagnosed and treated for C trachomatis between October 1993 and December 1994 was conducted (43 received patient delivered partner medication (PDPM) and 135 received partner referral cards). Women were retested before or at their annual visit. RESULTS The mean time of follow up was 17.7 months (SD 7.7). The PDPM group (n = 43) was similar to partner referral group (n = 135) for age, race, contraceptive method, history of an STD, and follow up time. The annual recurrent infection rate was lower among the PDPM group compared with the partner referral group (11.5% v 25.5%, p < 0.05). After adjusting for age in logistic regression, women in the PDPM group were less likely than women in the partner referral group to have an incident C trachomatis infection (OR 0.37, 95% CI 0.15-0.97, p < 0.05). CONCLUSION These findings suggest that patient delivered partner medication can protect women from recurrent C trachomatis infection compared with the standard partner referral approach. Prospective studies with larger sample sizes are under way.
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736
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Taha Z, Brown R, Wright D. A neural network approach to markerless measurement of human motion. BIOMEDICAL SCIENCES INSTRUMENTATION 1998; 33:441-6. [PMID: 9731400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Most automatic motion analysis system operates by tracking markers across a field of view. The markers are usually attached to the skin at the joints. For some applications such as measuring the motion of elderly and the disabled persons, this approach can be uncomfortable which ultimately can affect the motion itself. The protocol of some markers can also be a problem for example active markers using infra-red LEDs must continuously be in the field of view of the detectors at all times. This will impose restriction in the motion. Therefore a marker free method is an attractive proposition. Such an approach would allow the subject to move freely thus exhibiting a more natural movement. We have developed a PC based system which uses frames from the video or photographic capture of a motion in the frontal and sagital plane. Key frames are selected and co-ordinate positions of the joints are identified. Joint angles are calculated from these positions based on a multiple link model of the human figure. The angles are then used as training data for a fully connected neural network. The neural network generates a model of the captured motion which is used to reproduce closely the actual motion.
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737
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Hill DA, Seaton RA, Cameron FM, McLellan A, Brown R, France AJ. Severe sepsis caused by Mobiluncus curtisii subsp. curtisii in a previously healthy female: case report and review. J Infect 1998; 37:194-6. [PMID: 9821100 DOI: 10.1016/s0163-4453(98)80180-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
We present the case of a 54-year-old female with life-threatening septicaemia due to Mobiluncus curtisii subsp. curtisii. Her admission was complicated by septic shock, renal failure, disseminated intravascular coagulation, the adult respiratory distress syndrome and spontaneous splenic rupture. The patient survived with full intensive care support and intravenous ceftriaxone. Extra-genital infection with Mobiluncus species is rarely diagnosed and has been confined to breast abscesses and non-life-threatening bacteraemia. A review of extra-genital infections with Mobiluncus species is presented.
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738
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Pridham K, Brown R, Sondel S, Green C, Wedel NY, Lai HC. Transition time to full nipple feeding for premature infants with a history of lung disease. J Obstet Gynecol Neonatal Nurs 1998; 27:533-45. [PMID: 9773365 DOI: 10.1111/j.1552-6909.1998.tb02620.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
OBJECTIVE To (a) explore the contribution of infant, environmental, and historical factors to the number of days from initiation to achievement of full nipple feeding (transition time) for premature infants with a history of lung disease; (b) examine differences in the contribution of infant and environmental factors to transition time made by historical era, either earlier (in the 1980s) or later (in the 1990s); and (c) compare, within eras, the contribution to transition time of infant and environmental factors for infants with each lung diagnosis, respiratory distress syndrome (RDS) without bronchopulmonary dysplasia (BPD) or BPD. DESIGN Data were collected at two midwestern hospitals from the records of premature infants with a diagnosis of either RDS without BPD or BPD. The influence on transition time of infant, environmental and historical factors was assessed with the Cox proportional hazards model. This analytic model, a form of regression analysis, also was used to explore how era influenced the contribution to transition time of infant and environmental factors. Finally, the contribution to transition time of infant and environmental factors was examined within diagnostic group for each era. SAMPLE The hospital records audited were for infants who were 32 weeks gestational age or less with weight appropriate for gestational age. The number in each diagnostic group for each era was (a) BPD--Early, n = 35; (b) RDS--Early, n = 21; (c) BPD--Late, n = 21; and (d) RDS--Late, n = 15). RESULTS All three types of factors (infant, environmental, and historical) contributed significantly (p < .05) to shortening or lengthening transition time. A diagnosis of BPD lengthened transition time only in the early era. Across both eras, the number of days on tube feedings significantly lengthened transition time, and the older the infant in postconceptional age (PCA) at initiation of nipple feeding, the shorter the transition time. CONCLUSION The contribution of infant, environmental, and historical factors to transition time confirmed the basic structure of the theoretical model of transition time for premature infants with a history of lung disease. The influence of era on the contributions to transition time of infant and environmental factors suggests that care policy and practice have shortened the transition time. Although the current findings support the basic structure of the theoretical model for infants with either RDS or BPD, the marginally significant (p < .10) shortening effect of PCA on transition time for infants with BPD in both eras suggests that advancement to full nipple feeding may be limited by neurodevelopmental capacities, including respiratory control. How these capacities can be supported for advancement to full nipple feeding is a challenge for nursing practice and research.
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739
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McDonald AC, Brown R. Induction of p53-dependent and p53-independent cellular responses by topoisomerase 1 inhibitors. Br J Cancer 1998; 78:745-51. [PMID: 9743293 PMCID: PMC2062955 DOI: 10.1038/bjc.1998.571] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
We have previously shown that loss of p53 function in A2780 human ovarian adenocarcinoma cells confers increased clonogenic resistance to several DNA-damaging agents, but not to taxol or camptothecin. We have now extended these studies, comparing wild-type p53-expressing A2780 cells with isogenic derivatives transfected with a dominant negative mutant (143; val to ala) p53. We show that, as well as retaining equivalent clonogenic sensitivity to camptothecin, mutant p53 transfectants of A2780 cells do not acquire significantly increased resistance to the camptothecin analogues topotecan and SN-38, the active metabolite of CPT-11. Compared with vector-alone transfectants they are, however, relatively (2.2-fold) resistant to GI 147211, a further camptothecin analogue undergoing clinical trial. Treatment of A2780 with camptothecin and each analogue produces an increase, maximal at 24-48 h after drug exposure, of cells in the G2/M phase of the cell cycle and a decrease in both G1 and S-phase cells. The G2 arrest is independent of p53 function for camptothecin and the three analogues. All four compounds can induce apoptosis in A2780, which is reduced in mutant p53 transfectants, as measured using the terminal DNA transferase-mediated b-d UTP nick end labelling (TUNEL) assay. Thus, although p53-dependent apoptosis is induced by camptothecin, topotecan and SN-38 in this human ovarian carcinoma cell line, these drugs induce p53-independent death, as measured by clonogenic assay.
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740
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Daniels JT, Occleston NL, Crowston JG, Cordeiro MF, Alexander RA, Wilkins M, Porter R, Brown R, Khaw PT. Understanding and controlling the scarring response: the contribution of histology and microscopy. Microsc Res Tech 1998; 42:317-33. [PMID: 9766427 DOI: 10.1002/(sici)1097-0029(19980901)42:5<317::aid-jemt3>3.0.co;2-m] [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: 11/05/2022]
Abstract
In response to injury, the body usually initiates a full and swift wound healing response resulting in reconstructed, repaired tissue. In certain instances, due to a variety of factors, this may not happen, an example being chronic granulating venous leg ulcers. At the other extreme, the wound may heal excessively, producing disabling hypertrophic scarring such as can occur following large, deep burn injuries. Our group is interested in the surgical treatment of the eye disease glaucoma. As will be explained, the successful surgical treatment of this disease depends on a reduced scarring response at the end of wound healing. The purpose of this article is to give an overview of our microscopic and histological experimental work which has furthered our understanding of tissue repair, particularly the scarring response and its potential modification for successful glaucoma surgery.
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741
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Sing M, Brown R, Hill SC. The consequences of paying Medicare managed care plans their costs. INQUIRY : A JOURNAL OF MEDICAL CARE ORGANIZATION, PROVISION AND FINANCING 1998; 35:210-22. [PMID: 9719788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
This study examines 1993 Medicare expenditures for enrollees in 63 managed care plans that were reimbursed on a cost basis. We find that government spending for enrollees in cost-reimbursed plans in 1993 was substantially greater than it would have been had these enrollees instead received care in traditional fee-for-service Medicare or in a Medicare risk plan. The increase was due entirely to the much higher expenditures for Part B services under cost reimbursement. The findings suggest that Medicare cost reimbursement of health plans should be eliminated or significantly modified.
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742
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Brown R. East Germans succeed. Nature 1998; 394:613. [PMID: 9716123 DOI: 10.1038/29161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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743
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Smith H, Gooding S, Brown R, Frew A. Evaluation of readability and accuracy of information leaflets in general practice for patients with asthma. BMJ (CLINICAL RESEARCH ED.) 1998; 317:264-5. [PMID: 9677221 PMCID: PMC28620 DOI: 10.1136/bmj.317.7153.264] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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744
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Garcia-Sanchez F, Pizzorno G, Fu SQ, Nanakorn T, Krause DS, Liang J, Adams E, Leffert JJ, Yin LH, Cooperberg MR, Hanania E, Wang WL, Won JH, Peng XY, Cote R, Brown R, Burtness B, Giles R, Crystal R, Deisseroth AB. Cytosine deaminase adenoviral vector and 5-fluorocytosine selectively reduce breast cancer cells 1 million-fold when they contaminate hematopoietic cells: a potential purging method for autologous transplantation. Blood 1998; 92:672-82. [PMID: 9657770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Ad.CMV-CD is a replication incompetent adenoviral vector carrying a cytomegalovirus (CMV)-driven transcription unit of the cytosine deaminase (CD) gene. The CD transcription unit in this vector catalyzes the deamination of the nontoxic pro-drug, 5-fluorocytosine (5-FC), thus converting it to the cytotoxic drug 5-fluorouracil (5-FU). This adenoviral vector prodrug activation system has been proposed for use in selectively sensitizing breast cancer cells, which may contaminate collections of autologous stem cells products from breast cancer patients, to the toxic effects of 5-FC, without damaging the reconstitutive capability of the normal hematopoietic cells. This system could conceivably kill even the nondividing breast cancer cells, because the levels of 5-FU generated by this system are 10 to 30 times that associated with systemic administration of 5-FU. The incorporation of 5-FU into mRNA at these high levels is sufficient to disrupt mRNA processing and protein synthesis so that even nondividing cells die of protein starvation. To test if the CD adenoviral vector sensitizes breast cancer cells to 5-FC, we exposed primary explants of normal human mammary epithelial cells (HMECs) and the established breast cancer cell (BCC) lines MCF-7 and MDA-MB-453 to the Ad.CMV-CD for 90 minutes. This produced a 100-fold sensitization of these epithelial cells to the effects of 48 hours of exposure to 5-FC. We next tested the selectivity of this system for BCC. When peripheral blood mononuclear cells (PBMCs), collected from cancer patients during the recovery phase from conventional dose chemotherapy-induced myelosuppression, were exposed to the Ad.CMV-CD for 90 minutes in serum-free conditions, little or no detectable conversion of 5-FC into 5-FU was seen even after 48 hours of exposure to high doses of 5-FC. In contrast, 70% of 5-FC was converted into the cytotoxic agent 5-FU when MCF-7 breast cancer cells (BCCs) were exposed to the same Ad.CMV-CD vector followed by 5-FC for 48 hours. All of the BCC lines tested were shown to be sensitive to infection by adenoviral vectors when exposed to a recombinant adenoviral vector containing the reporter gene betagalactosidase (Ad.CMV-betagal). In contrast, less than 1% of the CD34-selected cells and their more immature subsets, such as the CD34+CD38- or CD34(+)CD33- subpopulations, were positive for infection by the Ad.CMV-betagal vector, as judged by fluorescence-activated cell sorting (FACS) analysis, when exposed to the adenoviral vector under conditions that did not commit the early hematopoietic precursor cells to maturation. When artificial mixtures of hematopoietic cells and BCCs were exposed for 90 minutes to the Ad.CMV-CD vector and to 5-FC for 10 days or more, a greater than 1 million fold reduction in the number of BCCs, as measured by colony-limiting dilution assays, was observed. To test if the conditions were damaging for the hematopoietic reconstituting cells, marrow cells collected from 5-FU-treated male donor mice were incubated with the cytosine deaminase adenoviral vector and then exposed to 5-FC either for 4 days in vitro before transplantation or for 14 days immediately after transplantation in vivo. There was no significant decrease in the reconstituting capability of the male marrow cells, as measured by their persistence in female irradiated recipients for up to 6 months after transplantation. These observations suggest that adenovirus-mediated gene transfer of the Escherichia coli cytosine deaminase gene followed by exposure to the nontoxic pro-drug 5-FC may be a potential strategy to selectively reduce the level of contaminating BCCs in collections of hematopoietic cells used for autografts in breast cancer patients.
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745
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Khoury H, Adkins D, Zehnbauer B, Goodnough L, Brown R, Safdar S, DiPersio JF. Essential thrombocythemia after allogeneic bone marrow transplantation for chronic myelogenous leukemia. Bone Marrow Transplant 1998; 22:107-9. [PMID: 9678805 DOI: 10.1038/sj.bmt.1701292] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Allogeneic transplant recipients are at high risk of developing secondary malignancies as a late complication of therapy. We report a case of essential thrombocythemia occurring 8 years following bone marrow transplantation (BMT) for chronic myelogenous leukemia.
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746
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Dehal SA, Kaplan MA, Brown R, Robinson TM, Chatwani A. Clinically inapparent tuboovarian actinomycosis in a woman with an IUD. A case report. THE JOURNAL OF REPRODUCTIVE MEDICINE 1998; 43:595-7. [PMID: 9693412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND The consequences and management of asymptomatic Actinomyces-like organisms detected on cervical cytologic smears continue to be controversial. CASE A unilateral tuboovarian actinomycotic abscess was discovered in a woman who had undergone a hysterectomy for uterine leiomyomas. She had had an intrauterine device in place for many years without any symptoms of pelvic inflammatory disease. CONCLUSION Ascending infection of the upper genital tract by Actinomyces may be clinically inapparent. When Actinomyces-like organisms aer detected on cervical cytologic smears, removal of an intrauterine device should be considered.
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747
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Sebire NJ, Snijders RJM, Brown R, Southall T, Nicolaides KH. Detection of sex chromosome abnormalities by nuchal translucency screening at 10–14 weeks. Prenat Diagn 1998. [DOI: 10.1002/(sici)1097-0223(199806)18:6<581::aid-pd301>3.0.co;2-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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748
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Sebire NJ, Snijders RJ, Brown R, Southall T, Nicolaides KH. Detection of sex chromosome abnormalities by nuchal translucency screening at 10-14 weeks. Prenat Diagn 1998; 18:581-4. [PMID: 9664603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
At 10-14 weeks of gestation more than 80 per cent of fetuses affected by trisomy 21 can be detected by a screening programme based on a combination of maternal age and fetal nuchal translucency thickness (NT). The screen positive group in such a programme also identifies fetuses with sex chromosome abnormalities. In this ongoing multicentre screening study, involving 61,972 singleton pregnancies, 53 cases of sex chromosome abnormalities were identified. The fetal NT was above the 95th centile in 87.9 per cent of the 33 cases with 45,XO, and in 40 per cent of the 20 cases with 47,XXX, 47,XYY or 47,XXX. However, it was estimated that at 12 weeks of gestation our population would contain 42 cases with 45,XO and 104 cases with 47,XXY, 47,XYY or 47,XXX. Since the rate of intra-uterine lethality, between 12 and 40 weeks of gestation, is about 65 per cent for 45,XO and four per cent for 47,XXY, 47,XYY or 47,XXX, the respective number of livebirths with these chromosomal abnormalities would have been 15 and 100, respectively, without prenatal diagnosis. Assuming that all intra-uterine deaths are from those with increased NT, screening for trisomy 21 by maternal age and fetal NT would have identified only 20 per cent of potential livebirths in the 45,XO group and nine per cent of those with 47,XXY, 47,XYY or 47,XXX.
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749
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Jones NA, Turner J, McIlwrath AJ, Brown R, Dive C. Cisplatin- and paclitaxel-induced apoptosis of ovarian carcinoma cells and the relationship between bax and bak up-regulation and the functional status of p53. Mol Pharmacol 1998; 53:819-26. [PMID: 9584207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
We investigated the roles of p53 and Bcl-2 homologues in the induction of apoptosis by cisplatin and paclitaxel in wild-type p53-expressing human ovarian carcinoma cells and cisplatin-resistant derivatives that have lost p53 function. Cisplatin induced apoptosis in parental A2780 but not in cisplatin-resistant A2780/cp70 cells, whereas paclitaxel induced apoptosis in both cell lines. Immunoprecipitation of p53 using antibodies specific for p53 conformation (pAb 1620 and pAb 240) showed that there were no relative changes in p53 conformation before and after cisplatin treatment in either cell line. A2780/cp70 cells have lost p53 function, yet they have wild-type p53 gene sequence. However, A2780/cp70 cells constitutively express more p53 in a form detected by pAb 240, an antibody that also detects mutant conformations of p53 that are transcriptionally inactive. There were no changes in levels of Bcl-2, Bcl-XL, or 24-kDa Bax over 72 hr after exposure to cisplatin or paclitaxel, but each agent led to up-regulation of Bak and 21-kDa Bax in A2780 cells. Paclitaxel, but not cisplatin, increased Bak and 21-kDa Bax levels in A2780/cp70 cells. These data suggest that apoptosis in A2780 and A2780/cp70 is associated with an increased level of Bak and 21 kDa Bax after drug-induced damage and that functional p53 may be required for this effect after cisplatin but not after paclitaxel.
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750
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Shaw G, Brown R, Bromiley P. Strategic stories: how 3M is rewriting business planning. HARVARD BUSINESS REVIEW 1998; 76:41-50. [PMID: 10179653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Virtually all business plans are written as a list of bullet points. Despite the skill or knowledge of their authors, these plans usually aren't anything more than lists of "good things to do." For example: Increase sales by 10%. Reduce distribution costs by 5%. Develop a synergistic vision for traditional products. Rarely do these lists reflect deep thought or inspire commitment. Worse, they don't specify critical relationships between the points, and they can't demonstrate how the goals will be achieved. 3M executive Gordon Shaw began looking for a more coherent and compelling way to present business plans. He found it in the form of strategic stories. Telling stories was already a habit of mind at 3M. Stories about the advent of Post-it Notes and the invention of masking tape help define 3M's identity. They're part of the way people at 3M explain themselves to their customers and to one another. Shaw and his coauthors examine how business plans can be transformed into strategic narratives. By painting a picture of the market, the competition, and the strategy needed to beat the competition, these narratives can fill in the spaces around the bullet points for those who will approve and those who will implement the strategy. When people can locate themselves in the story, their sense of commitment and involvement is enhanced. By conveying a powerful impression of the process of winning, narrative plans can mobilize an entire organization.
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