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1.
We studied the relation between the plasma concentration of brain natriuretic peptide (BNP) and echocardiographic findings to determine the sensitivity of BNP as an indicator of left-ventricular dysfunction in elderly patients with various cardiovascular diseases. The plasma concentration of BNP was positively correlated with left-ventricular end-diastolic and end-systolic dimensions (LVEDD and LVESD, respectively) and inversely correlated with the left-ventricular ejection fraction (LVEF) in patients with prior myocardial infarction, dilated cardiomyopathy, and valvular heart disease. The plasma concentration of BNP decreased significantly in association with an increase in LVEF and decreases in LVEDD and LVESD in patients with congestive heart failure following therapy. These observations indicate that the plasma concentration of BNP is a sensitive marker of impaired left-ventricular function in elderly patients with various cardiovascular diseases and may be useful for evaluating the improvement in left-ventricular function and the efficacy of therapy in patients with congestive heart failure.  相似文献   

2.
Left-ventricular angiography was performed in 28 patients after measuring ascending aortic and left ventricular pressures and during isometric exercise (hand grip, 0.3-0.4 kg/cm2 for 3 min). In 13 patients coronary blood flow was measured at rest and during hand-grip exercise by means of the argon method. Eight patients without heart disease served as controls. In 14 patients with coronary heart disease abnormal left-ventricular kinetics, demonstrated already at rest, got worse during hand-grip exercise. In five patients with normal left-ventricular angiograms at rest hypokinesia and dyskinesia occurred during isometric exercise. The coronary artery supplying the abnormal ventricular wall had a 50-75% decrease in diameter. One patients with isolated 25% stenosis had normal left-ventricular kinetics both at rest and on hand-grip exercise. In all patients coronary blood flow rose by 60-90% during isometric exercise. It iducing a significant rise in myocardial oxygen demand and increased coronary blood flow.  相似文献   

3.
Incidence and clinical significance of cardiopulmonary complications of acute cerebral lesions are still unclear. Neurogenic pulmonary edema (NPE) is characterized as an acute, protein-rich lung edema occurring shortly after cerebral lesions associated with an acute rise of intracranial pressure. NPE is infrequently diagnosed, usually in association with head trauma. Pathophysiological mechanisms include a rise of the pulmonary vascular hydrostatic pressure either due to sympathetic innervation with pulmonary vasoconstriction or increased left-atrial pressure following systemic arterial hypertension or an increase in pulmonary capillary permeability. In contrast to NPE, cardiac complications are frequently observed, most consistently in patients with subarachnoid hemorrhage. Typical ECG changes are repolarization abnormalities, similar to those observed in coronary heart disease, and cardiac arrhythmias. The CK-MB may be slightly elevated; echocardiographic findings show a depressed left-ventricular function. Pathological examination reveals myofibrillar necrosis. Cardiac complications are explained with overactivity of the sympathetic innervation and high levels of circulating catecholamines. For adequate treatment, close cardiac monitoring is required in all patients with acute cerebral lesions.  相似文献   

4.
According to the principles of probabilistic analysis, sensitivity and specificity of a diagnostic test are fixed values. Nevertheless, most authors consider them to be inconstant values, specially when applied to the diagnosis of coronary heart disease by exercise stress test. In this paper, we review the basic concepts on sensitivity and specificity of diagnostic tests and try to explain their supposed variability, when related to exercise test, as a function of undue comparison between ST-segment response and the findings of cinecoronariography. Based on the essential difference between coronary heart disease and ischemic heart disease, we demonstrate why such an equivocal comparison can lead to false results of sensitivity and specificity of exercise tests relative to coronary heart disease. As a result, their alleged variability depends most on the prevalence of ischemia throughout the spectrum of coronary heart disease in the studied population. As a matter of fact, unless one can rely on a method as a gold standard for the diagnosis of ischemic heart disease, the real sensitivity and specificity of exercise stress test should be considered as unknown values.  相似文献   

5.
BACKGROUND: In most previous epidemiological studies on the prevalence of chronic heart failure (CHF) the disorder has been defined on clinical criteria. In a cross-sectional survey of 2000 men and women aged 25-74, randomly sampled from one geographical area, we assessed left-ventricular systolic function by echocardiography. METHODS: 1640 (83%) of those invited took part. They completed a questionnaire on current medication, history, and symptoms of breathlessness. Blood pressure was measured and electrocardiography (ECG) and echocardiography were done. Left-ventricular ejection fraction was measurable in 1467 (89.5%) participants by the biplane Simpson's rate method. FINDINGS: The mean left-ventricular ejection fraction was 47.3%. The prevalence of definite left-ventricular systolic dysfunction (defined as a left-ventricular ejection fraction < or = 30%) was 2.9% overall (43 participants); it increased with age and was higher in men than in women (4.0 vs 2.0%). The left-ventricular systolic dysfunction was symptomatic in 1.5% of participants and asymptomatic in 1.4%, 83% of participants with left-ventricular systolic dysfunction had evidence of ischaemic heart disease (IHD) from history or ECG criteria compared with 21% of those without this abnormality (p < 0.001). Hypertension was also more common in those with left-ventricular systolic dysfunction (72 vs 38%, p < 0.001), but there was no difference between those with and without left-ventricular systolic dysfunction in the rate of hypertension without IHD. INTERPRETATION: Left-ventricular systolic dysfunction was at least twice as common as symptomatic heart failure defined by clinical criteria. The main risk factors are IHD and hypertension in the presence of IHD; screening of such high-risk groups for left-ventricular systolic dysfunction should be considered.  相似文献   

6.
In a 4 1/2 year period fetal, echocardiographic studies were performed on 1600 fetuses. In 55 with arrhythmia, 44 had supraventricular ectopic beats, resolved in all, and none had heart disease. Sustained arrhythmias occurred in 11 fetuses. Atrial flutter was present in 3 all with heart disease (Ebstein disease, right atrial tumour and WPW diagnosed after birth). Another 3 fetuses had supraventricular tachycardia (SVT), all with a normal heart. In the bradycardia group, 2 had complete heart block (CHB) associated with AVSD; 2 sinus bradycardia and one had non conducted atrial ectopic beats. Digoxin was the first choice drug for tachyarrhythmia therapy; association with Verapamil, Flecainide, Quinidine and Procainamide was used in 4 of the 6. One fetus with CHB received Orciprenaline with no results. Atrial flutter resolved or improved; in SVT 2 fetuses converted to sinus rhythm and one died in utero. All fetuses with CHB died in cardiac failure. Mortality was 27% (3 cases) in utero and global 36%. In our experience most fetal arrhythmias (90%) were transitory ectopic beats or non lasting bradycardia in normal heart and did not trigger other kinds of arrhythmias. In sustained arrhythmias, heart failure and heart disease had a negative effect on prognosis.  相似文献   

7.
Clinical reports indicate that cyclosporine is able to induce heart failure without rejection after heart transplantation. This supposition is supported by ex vivo animal studies, yet ex vivo studies do not account for the potential of counter-regulatory mechanisms, and the clinical observations seem rare in comparison with the number of patients treated with cyclosporine. We hypothesized that cyclosporine administration to rats would fail to exhibit any effect on myocardial contractility in vivo notwithstanding a negative influence ex vivo. Transthoracic echocardiographic examinations (two-dimensional targeted M-mode tracings) were done in a blinded fashion before and after 1-week treatment of rats (10 or 20 mg/kg/day cyclosporine i.p. vs. vehicle). After excision of the hearts, contractility and changes in coronary tone were determined ex vivo during flow-constant perfusion. Neither cyclosporine nor vehicle treatment resulted in changes of echocardiographic parameters (left ventricular diameter, fractional shortening). The heart rate was significantly increased in the high-dose cyclosporine group. This group showed a significant 38% reduction of contractility during the subsequent perfusion ex vivo, whereas low-dose cyclosporine or vehicle had no effect on myocardial performance. Vasoconstriction did not account for this impairment, because coronary tone was unaltered. Cyclosporine, given in doses used in animal studies, impairs myocardial contractility ex vivo but fails to exhibit any effect on myocardial performance in vivo, possibly because of an increase in sympathetic tone. Considering that the denervated transplanted heart in humans is even sensitized to adrenergic stimuli, our finding makes unlikely a clinical contribution of cyclosporine to failure after orthotopic heart transplantation.  相似文献   

8.
The availability of basic and reliable data on cardiovascular problems in Africans is limited and this hinders the presentation of a comprehensive review of the subject. Nevertheless, there is a strong suggestion that the spectrum and pattern of cardiovascular disorders in Africa is rapidly becoming indistinguishable from that observed in developed countries. The classic risk factors appear to be on the rise and smoking may attain levels equal to or exceeding those in many developed countries. Infectious and inflammatory cardiovascular conditions may still be the most common, although limitations in the technology available for accurate diagnosis make this difficult to verify. Rheumatic fever and rheumatic heart disease remain common, and the potential for educational and other preventive strategies is being realized in many countries. Hypertension at frequencies exceeding 5-10% in most rural areas and 12% in most urban areas, together with complications such as stroke, heart failure and renal failure, are leading causes of morbidity and mortality. Hypertension is the major public health problem in most African countries. The cardiomyopathies are a common problem, and the limited availability of specific diagnostic procedures is matched by limited therapeutic options for most Africans. The prevalence of atherosclerosis and coronary artery disease and its complications, such as myocardial infarction and other degenerative disorders, remains low, but the situation is rapidly changing, especially in urban areas where appropriate diagnostic capabilities exist. It is thought that changes or modifications in lifestyle, risk-prone behaviour, diet, cultural attitudes and certain other consequences of rapid urbanization and demographic tendencies largely explain the observed trends.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

9.
Comparison of patients treated for chronic heart failure at a large hospital with patients included in major treatment studies published during the past ten years yielded important information. The former series was characterised by greater proportions of the elderly and of women than were the series recruited to the often cited ACE (angiotensin-converting enzyme) inhibitor studies. Although only patients with systolic dysfunction were recruited to the latter studies, a substantial body of evidence suggests the prevalence of severe heart failure among patients with normal systolic function to increase with increasing age. Thus, as many as 50 per cent of all elderly patients with chronic heart failure may have normal systolic function. In most cases, the heart failure is probably due to diastolic dysfunction, a condition that still lacks both a simple diagnostic procedure and a well-documented treatment.  相似文献   

10.
BACKGROUND: There is accumulating evidence that inflammatory cytokines have an important role in the pathogenesis of heart failure. Plasma concentrations of tumour necrosis factor alpha (TNF-alpha) are high in heart failure and have been correlated with the severity of symptoms. Pentoxifylline suppresses the production of TNF-alpha. This study aimed to assess the effects of pentoxifylline on left-ventricular function and functional class in patients with idiopathic dilated cardiomyopathy. METHODS: We undertook a single-centre, prospective, double-blind, randomised, placebo-controlled trial, in which 28 patients with idiopathic dilated cardiomyopathy were assigned pentoxifylline 400 mg three times daily or matching placebo. Clinical, echocardiographic, and radionuclide assessments were done at baseline and after 6 months of treatment. Primary endpoints were New York Heart Association (NYHA) functional class and left-ventricular function. FINDINGS: Baseline characteristics were similar in the two groups. Four patients died during the study period, all in the placebo group. After 6 months of treatment, the proportion of patients in NYHA functional class I or II was higher in the pentoxifylline group than in the placebo group (14/14 vs 10/14; p=0.01), and ejection fraction was higher in the pentoxifylline group than in the placebo group (mean 38.7% [SD 15.0] vs 26.8% [11.0], p=0.04). At 6 months, TNF-alpha plasma concentrations were significantly lower in the pentoxifylline-treated group than in the placebo group (2.1 [1.0] vs 6.5 [5.0] pg/mL, p=0.001). INTERPRETATION: Our results suggest that pentoxifylline improves symptoms and left-ventricular systolic function in patients with idiopathic dilated cardiomyopathy. These results must be confirmed in larger-scale trials.  相似文献   

11.
Diabetes mellitus is associated with an inordinately high risk of virtually all manifestations of cardiovascular-renal disease including atherosclerotic coronary and peripheral vascular disease, congestive heart failure, stroke, nephropathy, and cardiomyopathy unassociated with coronary heart disease. Abnormalities in the renin-angiotensin-aldosterone-kinin (RAAK) cascade have been implicated in the pathogenesis and clinical expression of these cardiovascular-renal sequelae. Thus, pharmacological modulation of the RAAK system is an attractive therapeutic target in diabetes mellitus. Indeed, emerging data from human clinical studies appear to confirm this thesis.  相似文献   

12.
The goal of this study was to determine whether the isovolumically-contracting Langendorff heart could be used to assess changes in left-ventricular volume and contractile reserve in the mouse heart after myocardial infarction. Myocardial infarction (40 +/- 3% of the left ventricle by weight) was induced in CD-1 mice by ligation of the left-anterior descending coronary artery. Two weeks after infarction there was compensatory hypertrophy of the non-infarcted ventricle as indicated by increases in heart-to-body weight ratio (5.5 +/- 0.2 v 4.9 +/- 0.2 mg/g; P < 0.05; n = 12) and the expression of atrial natriuretic peptide mRNA (4.4 +/- 1.4-fold; P < 0.001; n = 4). Left-ventricular pressure-volume relationships were assessed in vitro in isovolumically-contracting hearts perfused with red cell-supplemented buffer (hematrocrit = 40%). Myocardial infarction caused left-ventricular dilation with a rightward-shift of the diastolic pressure-volume relationship. This was associated with reduced left-ventricular contractile function, as evidenced by a decrease in developed pressure over a range of left-ventricular volumes. Thus, it is feasible to use the isovolumically-contracting Langendorff preparation to assess the structural and functional consequences of left-ventricular remodeling in the mouse after a myocardial infarction.  相似文献   

13.
Early identification of patients with symptomless left-ventricular dysfunction and early pharmacologic intervention may have an impact on the outlook of patients with heart failure. Atrial natriuretic peptide (ANP) is a cardiac hormone that is released as a C-terminal (C-ANP) and an N-terminal peptide (N-ANP). Since N-ANP has reduced clearance rates compared with C-ANP, N-ANP circulates at higher concentrations. Based on the known increased concentration of C-ANP in symptomatic congestive heart failure, our study was designed to evaluate prospectively N-ANP profile and left-ventricular function in subjects with symptomless and symptomatic heart failure, and the role of plasma N-ANP as a marker for early identification of patients with heart failure. 180 patients who were referred for rest and exercise radionuclide angiography for evaluation of left-ventricular function were studied. Blood was taken for measurement of C-ANP and N-ANP before angiography. Patients were grouped according to New York Heart Association (NYHA) heart failure classification and left-ventricular function. Mean (SD) plasma N-ANP concentration in patients with symptomless left-ventricular dysfunction (NYHA class I, n = 70) was 243 (256) pmol/L (range 27-922 pmol/L), and was higher (p < 0.001) than in 25 control subjects (28 pmol/L). A plasma N-ANP concentration above 54 pmol/L (mean +/- 1.96SD of the control group) had a sensitivity of 90% and a specificity of 92% for detection of patients with symptomless left-ventricular dysfunction. We have shown that plasma N-ANP concentrations are significantly increased in patients with symptomless left-ventricular dysfunction and that this peptide can serve as a marker for diagnosis of such patients.  相似文献   

14.
Endothelin-1, a member of a novel family of regulatory peptides, is the most potent vasoconstrictor and pressor substance known. Endothelin-1 is a 21-amino-acid endothelium-derived peptide causing uniquely sustained vasoconstriction. In addition, endothelin-1 has pronounced effects on the coronary, renal and cerebral circulations, enhances responses to other vasoconstrictors, and is comitogenic. Recent studies have shown that the endothelins are essential for normal fetal development, and that endothelin-1 plays an important physiological role in the regulation of basal vascular tone and blood pressure in healthy humans. There is now also a wealth of evidence suggesting that endothelin-1 is a key mediator in a range of cardiovascular diseases associated with sustained vasoconstriction, such as chronic heart failure, and with vasospasm, such as subarachnoid haemorrhage. In addition, endothelin-1 appears to act in opposition to nitric oxide to promote the atherosclerotic process. There are a large number of oral and intravenously active endothelin antagonists entering clinical development and a number of clinical studies, particularly with endothelin receptor antagonists, are now under way. Such studies are beginning to define the role of the endothelins in cardiovascular disease and to confirm the potential of the endothelin system as an important new therapeutic target.  相似文献   

15.
Because controversies surround the increased negative inotropic effects of calcium antagonists in heart failure, other mechanisms may explain their lack of efficacy in this condition. We hypothesized that altered coronary sensitivity through endothelial dysfunctions may be involved. Our goal was to evaluate the effects of heart failure on coronary and cardiac sensitivity to the calcium antagonist diltiazem. Left ventricular developed pressure (LVP) and coronary flow (CF) were assessed in isovolumetrically beating, perfused, failing hearts from cardiomyopathic hamsters (UM-X7.1) and hearts from normal hamsters. Diltiazem concentration-response curves for both coronary dilation and its negative inotropic effects were charted under control conditions and in the presence of the specific nitric oxide (NO) synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME, 30 microM), and the cyclooxygenase inhibitor, indomethacin (10 microM). Diltiazem concentration-response curves for its negative inotropic action were similar in normal and failing hearts (IC50 1.2 and 2.3 microM, respectively). In contrast, the coronary dilator effects of diltiazem were impaired in failing hearts (EC50 for diltiazem-induced coronary dilation increased from 90 nM in normal hearts to 1.1 microM in failing hearts, p < 0.01). The involvement of endothelial dysfunctions in the observed coronary "desensitization" to diltiazem in heart failure was evaluated through the NO-synthase and cyclooxygenase pathways. Diltiazem concentration-response curves from failing hearts were not modified in the presence of L-NAME, whereas indomethacin normalized the coronary response to diltiazem in heart failure. These findings suggest that coronary "desensitization" to diltiazem occurs through parallel production and/or release of a vasoconstricting factor or factors originating from the cyclooxygenase pathway. Heart failure was not associated with increased cardiac sensitivity to diltiazem but rather with altered coronary sensitivity. These findings suggest that coronary desensitization may play a role in the lack of efficacy of diltiazem in heart failure and provide a better understanding of factors modulating the effects of calcium antagonists in heart failure.  相似文献   

16.
AIMS: As heart failure is a syndrome arising from another condition, such as coronary heart disease, it is rarely officially coded as the underlying cause of death regardless of the cause recorded by the physician at the time of certification. We sought to assess the true contribution of heart failure to overall mortality and coronary heart disease mortality and to examine how this contribution has changed over time. METHODS AND RESULTS: We carried out a retrospective analysis of all death certificates in Scotland between 1979 and 1992 for which heart failure was coded as the underlying or a contributory cause of death. From a total of 833622 deaths in Scotland between 1979 and 1992, heart failure was coded as the underlying cause in only 1.5% (13695), but as a contributory cause in a further 14.3% (126073). In 1979, 28.5% of male and 40.4% of female deaths attributed to coronary heart disease (coded as the underlying cause of death) also had a coding for heart failure. In 1992 these percentages had risen significantly to 34.1% and 44.8%, respectively (both P<0.001). Mortality rates for heart failure as the underlying or contributory cause of death, standardized by age and sex, fell significantly over the period studied in all ages and in both sexes: by 31% in men and 41% in women <65 years and 15.8% in men and 5.1% in women > or =65 years, respectively (P<0.01 for all changes). CONCLUSIONS: Death from heart failure is substantially underestimated by official statistics. Furthermore, one third or more of deaths currently attributed to coronary heart disease may be related to heart failure and this proportion appears to be increasing. While the absolute numbers of deaths caused by heart failure remains constant, this study is the first to show that standardized mortality rates are declining.  相似文献   

17.
New insights from basic laboratory studies and clinical trials have raised the intriguing possibility that the renin-angiotensin-kinin system may play a critical part in the pathophysiology of atherosclerosis. These studies suggest the possibility of an important new therapeutic role for ACE inhibitors: reduction in the risk of atherosclerosis and the complications of coronary artery disease. Ongoing large-scale trials will establish whether the findings from basic laboratory studies and clinical heart failure trials will apply to patients with ischemic heart disease irrespective of the presence or absence of left ventricular dysfunction.  相似文献   

18.
OBJECTIVES: To study the applicability of a newly developed echocardiographic scoring system in the assessment of carcinoid valvular heart disease. BACKGROUND: We investigated prospectively the development, progression and regression of carcinoid valvular heart disease in patients with carcinoid syndrome by serial echocardiography, correlating these features with urinary 5-HIAA levels and clinical data collected during therapy with somatostatin analog. METHODS: Twenty-three patients with carcinoid syndrome underwent serial echocardiographic examinations. An echocardiographic carcinoid valvular heart disease (CVHD) % score was determined from points assigned for tricuspid and pulmonary valve structure and function. RESULTS: Fifteen patients had no CVHD at study entry (group 1), while 8 patients had findings of CVHD (group 2). Five patients in group q developed new CVHD (1B), while one demonstrated progression of CVHD (2B). The remaining patients did not develop (1A) or had no progression of CVHD (2B). Despite major declines in 5-HIAA levels during therapy in most patients, CVHD did not regress. There were significantly lower levels of median baseline 5-HIAA (98.8 vs. 256 mg/24 h), posttreatment 5-HIAA (50.3 vs. 324 mg/24 h) and posttreatment 5-HIAA time integral (37.3 vs. 192 g/24 h* days) in group A vs. B (p < 0.05). However, only posttreatment 5-HIAA levels independently predicted the development or progression of CVHD by multiple step-wise regression analysis (p < 0.005), with a threshold observed in the 100 mg/24 h range. CONCLUSIONS: We designed a new echocardiographic scoring system to evaluate CVHD. Correlating echocardiographic scores with biochemical and clinical markers showed that only posttreatment 5-HIAA levels independently predicted the development or progression of CVHD. This study strengthens the association between serotonin secretion and CVHD, as well as introducing a new technique for serial follow-up of these patients.  相似文献   

19.
The aim of this study was to define the clinical, echocardiographic, and pathologic correlates of commissural dehiscence of aortic wall from the stent post of the porcine bioprostheses in the mitral position. This form of valve degeneration was found in 5 of 23 explanted mitral bioprostheses. A thickened, separated aortic wall at multiple commissural sites along with other evidence of valve degeneration was identified in the three patients who had chronic congestive heart failure. A large dehiscence at a single commissural site with otherwise normal valve morphology was present in the two patients who had acute heart failure. Two dimensional/Doppler echocardiography showed a prolapsing or a flail anteriorly positioned leaflet and an eccentric posteriorly directed mitral regurgitation jet in all patients. These echocardiographic findings in patients with a porcine bioprosthetic mitral valve should suggest commissural dehiscence from the aortic wall as a possible mechanism of valve failure. Exclusive involvement of the porcine aortic bioprosthesis placed in the mitral position along with involvement of strut of the bioprosthesis facing the aortic root in all cases suggests excessive hemodynamic stress on the valve in the mitral position and in particular on the anteriorly placed strut as the potential cause of this form of valve degeneration.  相似文献   

20.
Recent epidemiologic studies have suggested that cardiac disease in common in diabetics and may often have a noncoronary basis. To examine the status of the left ventricle, 17 adult-onset diabetics of familial type without hypertension or obesity underwent hemodynamic study and were compared to 9 controls of similar age. Of the 17, 12 subjects had no significant occlusive lesions by coronary angiography. From this group eight without heart failure had a modest, but significant, elevation of left ventricular end-diastolic pressure. End-diastolic and stroke volumes were reduced, but ejection fraction and mean rate of fiber shortening were within normal limits. The left ventricular end-diastolic pressure/volume ratio was significantly higher than controls. Afterload increments effected a significant increase of filling pressure compared to normals without a stroke volume response, consistent with a preclinical cardiomyopathy. Four patients with prior heart failure had similar but more extensive abnormalities. None had local dyskinesia by angiography, and lactate production was not observed during pacing-induced tachycardia. Left ventricular biopsy in two patients without ventricular decompensation showed interstitial collagen deposition with relatively normal muscle cells. These findings suggest a myopathic process without ischemia. Postmortem studies were performed in 11 uncomplicated diabetics. Nine were without significant obstructive disease of the proximal coronary arteries, and the majority succumbed with cardiac failure. On left ventricular sections, none had evident luminal narrowing of the intramural vessels. All nine exhibited periodic acid-Schiff-positive material in the interstitium. Collagen accumulation was present in perivascular loci, between myofibers, or as replacement fibrosis. Multiple samples of left ventricle and septum revealed enhanced triglyceride and cholesterol concentrations, as compared to controls. Thus, a diffuse extravascular abnormality may be a basis for cardiomyopathic features in diabetes.  相似文献   

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