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81.
82.
Detection of recombinant human erythropoietin abuse in athletes utilizing markers of altered erythropoiesis 总被引:11,自引:0,他引:11
Parisotto R Wu M Ashenden MJ Emslie KR Gore CJ Howe C Kazlauskas R Sharpe K Trout GJ Xie M 《Haematologica》2001,86(2):128-137
BACKGROUND AND OBJECTIVES: The detection of recombinant human erythropoietin (r-HuEPO) abuse by athletes remains problematic. The main aim of this study was to demonstrate that the five indirect markers of altered erythropoiesis identified in our earlier work were reliable evidence of current or recently discontinued r-HuEPO use. A subsidiary aim was to refine weightings of the five markers in the initial model using a much larger data set than in the pilot study. A final aim was to verify that the hematologic response to r-HuEPO did not differ between Caucasian and Asiatic subjects. DESIGN AND METHODS: Recreational athletes resident in Sydney, Australia (Sydney, n = 49; 16 women, 33 men) or Beijing, China (Beijing, n=24; 12 women, 12 men) were randomly assigned to r-HuEPO or placebo groups prior to a 25 day administration phase. Injections of r-HuEPO (or saline) were administered double-blind at a dose of 50 IU/kg three times per week, with oral iron (105 mg) or placebo supplements taken daily by all subjects. Blood profiles were monitored during and for 4 weeks after drug administration for hematocrit (Hct), reticulocyte hematocrit (RetHct), percent macrocytes (%Macro), serum erythropoietin (EPO) and soluble transferrin receptor (sTfr), since we had previously shown that these five variables were indicative of r-HuEPO use. RESULTS. The changes in Hct, RetHct, %Macro, EPO and sTfr in the Sydney trial were qualitatively very similar to the changes noted in our previous administration trial involving recreational athletes of similar genetic origin. Statistical models developed from Fisher's discriminant analysis were able to categorize the user and placebo groups correctly. The same hematologic response was demonstrated in Beijing athletes also administered r-HuEPO. INTERPRETATION AND CONCLUSIONS: This paper confirms that r-HuEPO administration causes a predictable and reproducible hematologic response. These markers are disturbed both during and for several weeks following r-HuEPO administration. This work establishes an indirect blood test which offers a useful means of detecting and deterring r-HuEPO abuse. Ethnicity did not influence the markers identified as being able to detect athletes who abuse r-HuEPO. 相似文献
83.
B. Douglas Smith Barbara J. Bambach Milada S. Vala James P. Barber Cheryl Enger Robert A. Brodsky Philip J. Burke Steven D. Gore & Richard J. Jones 《British journal of haematology》1998,102(4):1042-1049
Despite extensive investigation into mechanisms of drug resistance in acute myeloid leukaemia (AML), the aetiology of therapeutic resistance is unclear. We found that five leukaemia cell lines (K562, HL-60, CEM, CEM induced to overexpress bcl-2, and REH) displayed parallel sensitivity to four antileukaemia drugs with different mechanisms of action, with K562 generally being the least sensitive and REH being the most sensitive. The amount of spontaneous apoptosis in the cell lines after serum-free culture paralleled their drug sensitivity: K562 cells displayed the least apoptosis at 24 h (2.50 ± 0.24%) and REH the most (24.47 ± 8.22%). The extent of spontaneous apoptosis of leukaemic blasts from 39 patients with newly diagnosed de novo AML also correlated with the success of the intensive, infusional cytarabine-based induction therapy. There was a median of 19.5% (range 3.6–64%) apoptotic AML cells after 24 h of serum-free culture in patients who entered a complete remission compared with 4.2% (1.8–7.0%) apoptotic AML cells in patients who did not achieve a complete remission ( P = 0.0007). Thus, inhibited apoptosis was associated with both in vitro and in vivo pan-resistance to antileukaemic chemotherapy. The cause of inhibited apoptosis in AML is probably a function of interactions among multiple signals that influence apoptosis. Assessment of spontaneous apoptosis may serve as an important prognostic factor for AML. 相似文献
84.
A variety of methods for risk stratification after acute myocardial infarction have been successfully employed, however, little attention has been focused on patients who have received reperfusion therapy. The present report examines the utility of dipyridamole thallium scintigraphy in the prediction of late cardiac death or recurrent myocardial infarction in patients who have received thrombolytic therapy. Prospectively, 71 patients who presented with myocardial infarction and were treated with recombinant tissue plasminogen activator (and frequently percutaneous transluminal coronary angioplasty) were enrolled in the study. The primary end points during the follow-up period of nearly 2 years were recurrent infarction or death, which occurred in 10 patients. Although cardiac events were significantly related to either the performance of late myocardial revascularization or the presence of a residual coronary artery stenosis at discharge, no scintigraphic variable was found to be predictive of myocardial infarction or death. Thus, this report is the first to suggest limitation of scintigraphic techniques with regard to prognostic value in myocardial infarction survivors treated with reperfusion techniques. This selected population may have physiologic differences as compared with post-infarction studies performed before the advent of thrombolytic agents. Caution is therefore advised in extrapolating results of earlier reports to the ever increasing percentage of patients receiving recannalization therapy. 相似文献
85.
McCormick D Gurwitz JH Lessard D Yarzebski J Gore JM Goldberg RJ 《Archives of internal medicine》1999,159(6):561-567
BACKGROUND: For patients who have had a previous myocardial infarction (MI), the use of aspirin, beta-blockers, and lipid-lowering agents reduces the risk of recurrent MI and death. OBJECTIVE: To examine trends in and determinants of receipt of these 3 medications before hospitalization for recurrent acute MI (AMI). METHODS: The study population consisted of 1710 patients with a previous history of MI hospitalized with a validated recurrent AMI in all hospitals in Worcester, Mass, during 1986, 1988, 1990, 1991, 1993, and 1995. Logistic regression analyses were used to assess the effect of demographic, clinical, and temporal factors on the receipt of aspirin, beta-blockers, and lipid-lowering medications before hospital admission for recurrent AMI. RESULTS: More than 47% of patients in each study year were not receiving each medication before admission, although significant increases in use were noted over time for aspirin (from 13.5% to 52.6%), beta-blockers (from 33.2% to 44.4%), and lipid-lowering medications (from 0.8% to 11.7%). In multivariate analyses, advancing age was associated with not receiving aspirin (odds ratio [OR], 0.67; 95% confidence interval [CI], 0.51-0.89), lipid-lowering medications (OR, 0.14; 95% CI, 0.08-0.25), and beta-blockers (OR, 0.75; 95% CI, 0.57-1.00), although this effect was of borderline significance for beta-blockers. Being a woman was associated with not receiving aspirin (OR, 0.78; 95% CI, 0.62-0.98) but was positively associated with receiving lipid-lowering medications (OR, 1.59; 95% CI, 1.04-2.43). Coexisting medical conditions and concurrent use of other cardiovascular medications were also associated with receipt of each medication. CONCLUSION: Despite encouraging increases over time, the low absolute levels of receipt of medications shown to be efficacious in the long-term treatment of patients after an MI, and their variation by age and sex, suggest that substantial opportunities may exist to prevent recurrent AMIs through the increased use of aspirin, beta-blockers, and lipid-lowering medications. 相似文献
86.
Anti-M is usually a naturally occurring cold-reactive immunoglobulin M (IgM) antibody, often with an immunoglobulin G (IgG) component, and is seldom implicated in delayed haemolytic transfusion reactions (DHTR). However, cases have been reported. In the majority, a DHTR is not suspected until further blood is requested and a new antibody is detected on pretransfusion testing. We describe the case of a young man receiving therapy with interleukin-2 (IL-2) and interferon-alpha (IFN-alpha) for metastatic renal cell cancer who developed a clinically suspected DHTR that was confirmed serologically to be caused by anti-M, reactive at 37 degrees C. We discuss the possible role of his biochemotherapy in the development of the DHTR. 相似文献
87.
88.
Acute diarrhea is commonly caused by an infection. Severe acute diarrhea warrants immediate medical evaluation and hospitalization. Indications for stool studies include fever; bloody diarrhea; recent travel to an endemic area; recent antibiotics; immunosuppression; and occupational risks, such as food handlers. Noninfectious causes include inflammatory bowel disease, radiation enteritis, and intestinal ischemia. Management of severe acute diarrhea includes intravenous fluid rehydration and empiric antibiotics. Use of antidiarrheal agents is controversial when invasive pathogens are suspected. 相似文献
89.
Jobe AH Newnham JP Willet KE Moss TJ Gore Ervin M Padbury JF Sly P Ikegami M 《American journal of respiratory and critical care medicine》2000,162(5):1656-1661
Antenatal exposure to glucocorticoids, amnionitis, intraamniotic interleukin (IL)-1alpha, or endotoxin can improve postnatal lung function after preterm delivery. The relationship between early lung maturation and the dose and duration of a proinflammatory stimulus has not been evaluated. The effects of proinflammatory stimuli on fetal plasma cortisol also have not been evaluated. We hypothesized that intraamniotic endotoxin would induce early lung maturation in fetal sheep without increasing fetal cortisol. Intraamniotic injections of 1, 4, 20, or 100 mg of Escherichia coli 055:beta5 endotoxin caused 2-fold increases in compliance, 4- to 5-fold increases in lung gas volumes, and 20-fold increases in alveolar saturated phosphatidylcholine (Sat PC) when given 7 d before preterm delivery at 125 d gestation. Animals treated with 20 mg endotoxin for treatment to delivery intervals of 5 h to 15 d had no significant elevations in cord plasma cortisol levels. Increases in Sat PC in lung tissue and alveolar washes were detected 2 d after endotoxin treatment and lung function improved 4 d after endotoxin treatment. Two doses of endotoxin given 3 and 7 d or 7 and 15 d before treatment resulted in lung maturation responses equivalent to single dose comparison groups without elevations in cortisol. Early lung maturation induced by intraamniotic endotoxin in fetal sheep occurred without an increase in fetal plasma cortisol, indicating that endotoxin promoted lung maturation by a mechanism independent of cortisol. 相似文献
90.
Isabel Gauthier Michael J. Tarr Jill Moylan Adam W. Anderson Pawel Skudlarski John C. Gore 《Cognitive neuropsychology》2013,30(1-3):143-164
Functional magnetic resonance imaging was used to compare brain activation associated with basic-level (e.g. bird) and subordinate-level (e.g. eagle) processing for both visual and semantic judgements. We localised the putative face area for 11 subjects, who also performed visual matching judgements for pictures and aurally presented words. The middle fusiform and occipital gyri were recruited for subordinate minus basic visual judgements, reflecting additional perceptual processing. When the face area was localised individually for each subject, analyses in the middle fusiform gyri revealed that subordinate-level processing activated the individuals face area. We propose that what is unique about the way faces engage this region is the focal spatial distribution of the activation rather than the recruitment of the face per se. Eight subjects also performed semantic judgements on aurally presented basic- and subordinate-level words. The parahippocampal gyri were more activated for subordinate-level than basic-level semantic judgements. Finally, the left posterior inferior temporal gyrus was activated for subordinate-level judgements, both visual and semantic, as well as during passive viewing of faces. 相似文献