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Abstract
The emerging fields of graphene-based magnetic and spintronic devices require a deep understanding of the interface between graphene and ferromagnetic metals. This paper reports a detailed investigation at the nanometer level of the Fe-graphene interface carried out by angle-resolved photoemission, high-resolution photoemission from core levels, near edge X-ray absorption fine structure, scanning tunnelling microscopy and spin polarized density functional theory calculations. Quasi-free-standing graphene was grown on Pt(111), and the iron film was either deposited atop or intercalated beneath graphene. Calculations and experimental results show that iron strongly modifies the graphene band structure and lifts its π band spin degeneracy.
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Highly Crystalline Multimetallic Nanoframes with Three-Dimensional Electrocatalytic Surfaces. Science 2014; 343:1339-43. [DOI: 10.1126/science.1249061] [Citation(s) in RCA: 2051] [Impact Index Per Article: 205.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Abnormal spatial QRS-T angle, a marker of ventricular repolarisation, predicts serious ventricular arrhythmia in systemic sclerosis. Clin Exp Rheumatol 2012; 30:327-331. [PMID: 22510222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Accepted: 10/26/2011] [Indexed: 05/31/2023]
Abstract
OBJECTIVES Cardiac involvement may be under-diagnosed in asymptomatic patients with systemic sclerosis (SSc). Standard electrocardiography-derived spatial QRS-T angle (spQRS-Ta) is an established marker of ventricular repolarisation heterogeneity, and a strong independent predictor of cardiac morbidity and mortality, including sudden death, in the general population. We examined whether spQRS-Ta is abnormal in asymptomatic SSc patients and assessed its predictive value for possibly concurrent, serious ventricular arrhythmia. METHODS SpQRS-Ta and 24-hour Holter recordings were obtained from 69 SSc patients (aged 51±13 years, 63 women) without clinically evident cardiac involvement and having left ventricular ejection fraction at least 50% by echocardiography. 'Healthy' subjects matched 1:1 with patients for age, gender and body mass index served as controls. RESULTS SpQRS-Ta was wider in SSc (median value 15.6°, interquartile range 10.6-24.3°) than controls (10.5°, 7.3-13.5°, p=0.0001) and not associated with skin fibrosis extent or specific clinical manifestations and autoantibodies. Twenty-four-hour Holter recordings revealed couplets of ventricular beats in six (Lown class IVa) and non-sustained ventricular tachycardia in five patients (Lown class IVb); spQRS-Ta was wider in those eleven patients with serious ventricular arrhythmia than the remaining patients (24.9°, 14.9-31.3° vs. 14.4°, 9.6-22.3°; p=0.02). A spQRS-Ta>19.3° demonstrated 80% sensitivity and 68% specificity (area under the curve 0.81, p=0.02) to predict the presence of non-sustained ventricular tachycardia in Holter monitoring. CONCLUSIONS Ventricular repolarisation heterogeneity, as reflected by wider spQRS-Ta, is common in SSc. Increased spQRS-Ta could serve as a simple screening test for further investigation to identify patients at risk or prone to develop life-threatening ventricular arrhythmia.
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Best Oral Presentations (OP01-OP12). Rheumatology (Oxford) 2012. [DOI: 10.1093/rheumatology/ker437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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P1.14 FORMATION OF NEW ATHEROSCLEROTIC PLAQUES IN WELL CONTROLLED RHEUMATOID ARTHRITIS DEPENDS ON CLASSICAL CARDIOVASCULAR RISK FACTORS: A PROSPECTIVE LONGITUDINAL STUDY. Artery Res 2011. [DOI: 10.1016/j.artres.2011.10.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022] Open
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1086 Biochemical markers of bone remodeling as predictors of skeletal morbidity and outcome in patients with solid tumors metastatic to the skeleton receiving the biphosphonate zoledronic acid. EJC Suppl 2009. [DOI: 10.1016/s1359-6349(09)70379-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Weak molecular chemisorption of N(2)/Pt(111). JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2009; 21:264009. [PMID: 21828457 DOI: 10.1088/0953-8984/21/26/264009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The ordering in a higher-order-commensurate monolayer solid of Pt(111)- (3 × 3)-4 N(2), which has coexisting physisorbed and weakly chemisorbed N(2) species, is analyzed with model calculations. Density functional theory calculations are also used to evaluate properties of chemisorbed N(2) in a (2 × 2) unit cell on Pt(111). The relation of these results to the orientational ordering of N(2) on other metal surfaces is discussed.
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Modeling Ethanol Decomposition on Transition Metals: A Combined Application of Scaling and Brønsted−Evans−Polanyi Relations. J Am Chem Soc 2009; 131:5809-15. [DOI: 10.1021/ja8099322] [Citation(s) in RCA: 252] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
Mitral valve prolapse (MVP) is a benign valvular abnormality. However, an increased prevalence of MVP is reported in patients with systemic lupus erythematosus and autoimmune thyroid disease. Our aim was to evaluate whether the presence of MVP in healthy individuals might indicate a premature index of subclinical autoimmune disorder. A total of 75 individuals with MVP and 44 individuals without MVP were identified by echocardiography. Serum samples were examined for various organ and non-organ specific autoantibodies. In all, 35 of the 75 individuals with MVP had at least one autoantibody. ANA were detected in 17/75 in MVP(+) versus 1/44 in the MVP(-), (P < 0.05), and anti-ENA in 6/75 in the MVP(+) versus 0/44 in the control group, P = ns. In the MVP(+) group, thyroid autoantibodies, IgA and IgG RF were found at a statistically significant higher incidence, 16/75, 11/75 and 10/75 versus 1/44, 0/44 and 0/44 in the MVP(-)group, respectively (P < 0.05). The levels of IgG anticardiolipin antibodies were significantly higher in the MVP(+) group, P < 0.05. The presence of organ and non-organ specific autoantibodies in young healthy MVP(+) individuals insinuate the presence of subclinical autoimmunity and might suggest that autoimmune mechanisms might be involved in its pathogenesis. A follow-up of these individuals might elucidate whether MVP constitutes an early index of autoimmunity.
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Improvement of vascular endothelial function using the oral endothelin receptor antagonist bosentan in patients with systemic sclerosis. ACTA ACUST UNITED AC 2007; 56:1985-93. [PMID: 17530638 DOI: 10.1002/art.22634] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE Increased endothelin activity may play a role in the pathogenesis of vascular injury, a primary feature of systemic sclerosis (SSc; scleroderma). Our goal was to test the hypothesis that treatment with the oral endothelin receptor antagonist bosentan might improve vascular endothelial function in SSc patients. METHODS A 4-week, prospective, parallel-group study compared 12 SSc patients who did not receive bosentan treatment with 12 patients who did receive treatment (125 mg/day) for pulmonary hypertension and/or digital ulcers. There were no differences in demographic and clinical characteristics or medications between the 2 groups. Baseline endothelial dysfunction was documented by decreased brachial artery ultrasound-derived flow-mediated dilation (FMD%; <5.5). Pulse wave analysis, venous occlusion plethysmography, and measurement of serum vascular markers were performed in parallel. RESULTS FMD%, the main end point, increased significantly from a mean +/- SD of 3.1 +/- 1.3% to 8.4 +/- 2.6% after 4 weeks of bosentan treatment (P < 0.001, compared with a change from 2.4 +/- 1.6% to 2.4 +/- 2.2% in control patients). Arterial blood pressure, endothelium-independent vascular function, augmentation index, peripheral flow reserve, as well as circulating intercellular adhesion molecule 1, E-selectin, vascular endothelial growth factor, and endothelin 1 were not significantly affected by bosentan treatment. In patients continuously treated for 4 months, during which the dosage of bosentan remained at 125 mg/day (n = 5) or increased to 250 mg/day (n = 5), the 4-week results remained unchanged. CONCLUSION Small doses of bosentan improve endothelial function without affecting hemodynamic parameters or endothelial activation-related processes, thus supporting a direct, reversible effect of endothelin in SSc-associated vascular injury. A long-term, controlled trial to examine the potentially global clinical benefit of endothelin receptor blockade in patients with early SSc may be warranted.
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Abstract
In the present case-control study we aimed to investigate the association of common carotid arterial (CCA) stiffness with ischaemic stroke (IS) and to determine whether this relationship was independent of conventional risk factors including CCA intima-media thickness (CCA-IMT). CCA distensibility, defined as the change of CCA-diameter during the cardiac cycle, and CCA-IMT were evaluated by means of high-resolution B-mode carotid ultrasound examination in consecutive, first-ever IS patients (n=193) and in age- and sex-matched control subjects (n=106). The CCA distensibility (inverse of CCA stiffness) was significantly (P=0.007) lower in IS (0.353 mm, 95% CI: 0.326-0.379) than in control subjects (0.415 mm, 95% CI: 0.378-0.451) even after adjusting for blood pressure values, diastolic CCA-diameter and height. The multivariate logistic regression procedure selected CCA-IMT and CCA distensibility as the only independent predictor variables of IS. Each 1 SD increase in the CCA-IMT and each 1 SD decrease in the CCA distensibility independently increased the likelihood of IS by 167.0% (OR: 2.67, 95% CI: 1.80-3.96, P<0.001) and 59.0% (OR: 1.59, 95% CI: 1.22-2.07, P=0.001) respectively. Increased CCA stiffness is associated with IS independent of conventional risk factors and CCA-IMT. The causal interrelationship between the elastic properties of the CCA and the risk of stroke deserves further investigation by longitudinal studies.
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Common carotid artery intima-media thickness for the risk assessment of lacunar infarction versus intracerebral haemorrhage. J Neurol 2005; 252:1093-100. [PMID: 15906059 DOI: 10.1007/s00415-005-0821-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2004] [Revised: 11/28/2004] [Accepted: 01/25/2005] [Indexed: 10/25/2022]
Abstract
BACKGROUND AND PURPOSE Arterial hypertension is the major risk factor for intracerebral haemorrhage (ICH) and lacunar infarction (LI) and both types of cerebral lesions originate from pathology of the same deep perforating small arteries. We aimed to evaluate the relationship between vascular risk factors including common carotid artery intima-media thickness (CCA-IMT) with LI versus ICH. METHODS We prospectively collected data from 159 first ever stroke patients (67 cases with ICH and 92 cases with LI) with documented history of hypertension. All subjects underwent B-mode ultrasonographic measurements of the CCA-IMT. Logistic regression modelling was used to determine the factors (established vascular risk factors, severity and duration of hypertension, concomitant medications and CCA-IMT) that may significantly differentiate LI from ICH. RESULTS Patients with LI had significantly (p=0.002) larger CCA-IMT values (0.926 mm, 95% CI: 0.881-0.971) than subjects with ICH (0.815 mm, 95% CI: 0.762-0.868) even after adjusting for baseline characteristics and cardiovascular medications. The multivariate logistic regression procedure selected CCA-IMT, diabetes mellitus and hypercholesterolaemia as the only independent factors able to discriminate between LI and ICH. The risk for LI versus ICH increased continuously with increasing CCA-IMT. For each increment of 0.1 mm in CCA-IMT the probability of suffering from LI versus ICH increased by 36.6% (95 % CI: 13%-65.2%, p=0.001) even after adjustment for cardiovascular risk factors. CONCLUSIONS Increased CCA-IMT values are a factor favouring LI over ICH in hypertensive patients. The measurement of CCA-IMT may be a useful non-invasive diagnostic tool for the risk assessment of LI with respect to ICH in such patients.
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Abstract
OBJECTIVE The aim of this study was to investigate the endothelial status in young women with polycystic ovary syndrome (PCOS), using a simple and easily reproducible hemodynamic method combined with a biological marker and to evaluate the effect of metformin treatment on these parameters. DESIGN Descriptive clinical trial. METHODS Forty young women, 20 with PCOS and 20 normal women of similar age and body mass index were studied. Metformin (1700 mg daily) was administered for 6 months to the PCOS group. The endothelium status and the metabolic and hormonal profile were studied in both groups, as well as after metformin, by flow-mediated dilatation (FMD) on the brachial artery and by measurements of plasma endothelin-1 (ET-1) levels. RESULTS FMD was impaired in the PCOS group when compared with controls (3.24+/-0.71% vs 8.81+/-1.07% respectively, P<0.0001), but this difference normalized after metformin treatment (PCOS(post-metformin) vs controls: 8.17+/-1.26 vs 8.81+/-1.07%, P = 0.70) since the values significantly improved after metformin treatment (PCOS(pre-metformin) vs PCOS(post-metformin): 3.24+/-0.71 vs 8.17+/-1.26%, P=0.003). ET-1 levels were significantly higher in the PCOS women compared with the control group (7.23+/-0.50 vs 4.99+/-0.69 fmol/l, P=0.01), they improved significantly after metformin treatment (PCOS(pre-metformin) vs PCOS(post-metformin): 7.23+/-0.50 vs 3.57+/-0.60 fmol/l, P<0.0001) and their difference compared with the control group was reversed (PCOS(post-metformin) vs controls: 3.57+/-0.60 vs 4.99+/-0.69 fmol/l, P=0.13). Metformin administration improved hyperandrogenemia. However, in this study, mathematical methods used to assess insulin resistance failed to show any detected alteration after treatment with metformin. CONCLUSIONS PCOS women were found to exhibit endothelial dysfunction compared with controls, which was reversed 6 months after metformin administration.
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Abstract
OBJECTIVE To evaluate the relationship between systolic blood pressure (SBP) or diastolic blood pressure (DBP) on admission and early or late mortality in patients with acute stroke. DESIGN Prospective study of hospitalized first-ever stroke patients over 8 years. SETTING Stroke unit and medical wards in a University hospital. SUBJECTS A total of 1121 patients admitted within 24 h from stroke onset and followed up for 12 months. MAIN OUTCOME MEASURES Mortality at 1 and 12 months after stroke in relation to admission SBP and DBP. RESULTS Early and late mortality in patients with acute ischaemic or haemorrhagic stroke in relation to admission SBP and DBP followed a 'U-curve pattern'. After adjusting for known outcome predictors, the relative risk of 1-month and 1-year mortality associated with a 10-mmHg SBP increase above 130 mmHg (U-point of the curve) increased by 10.2% (95% CI: 4.2-16.6%) and 7.2% (95% CI: 2.2-12.3%), respectively. For every 10 mmHg SBP decrease, below the U-point, the relative risk of 1-month and 1-year mortality rose by 28.2% (95% CI: 8.6-51.3%) and 17.5% (95% CI: 3.1-34.0%), respectively. Low admission SBP-values were associated with heart failure (P < 0.001) and coronary artery disease (P = 0.006), whilst high values were associated with history of hypertension (P < 0.001) and lacunar stroke (P < 0.001). Death due to cerebral oedema was significantly (P = 0.005) more frequent in patients with high admission SBP-values, whereas death due to cardiovascular disease was more frequent (P = 0.004) in patients with low admission SBP-values. CONCLUSION Acute ischaemic or haemorrhagic stroke patients with high and low admission BP-values have a higher early and late mortality. Coincidence of heart disease is associated with low initial BP-values. Death due to neurological damage from brain oedema is associated with high initial BP-values.
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Arterial wall characteristics in patients with Adamantiades-Behçet's disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2003; 528:399-404. [PMID: 12918733 DOI: 10.1007/0-306-48382-3_82] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Abstract
OBJECTIVE The role of androgens in the pathogenesis of coronary artery disease (CAD) remains controversial. The length of the polyglutamine stretch of the transactivation domain (CAG repeat) of the androgen receptor (AR) inversely affects androgen activity. The aim of this study was to investigate the effect of this polymorphism of the AR gene in the extent of CAD in male patients. DESIGN AND PATIENTS The relationship of the length of the AR gene CAG repeat on the severity of CAD was examined in 131 men (36-86 years old) undergoing coronary angiography. MEASUREMENTS The severity of CAD was assessed by the number (0-3) of coronary vessels with > 50% reduction in the luminal diameter. The interaction of the AR gene polymorphism with the intima media thickness (IMT) of peripheral arteries and serum levels of sex steroids, insulin and biochemical parameters were also studied. RESULTS The upper quartile of CAG length (range 9-30) was > or = 23 repeats (longAR). The mean body mass index (BMI) of patients with shorter repeats (< 23; shortAR) was significantly lower than in men with longAR (26.1 vs. 27.6, respectively; P = 0.043 M-W Rank test). There was no correlation between the AR gene repeat length and serum testosterone. Oestradiol levels were significantly higher in longAR (0.19 +/- 0.08 nmol/l vs. 0.14 +/- 0.07 in shortAR, P = 0.031). This difference was independent of BMI. Men with shortAR had significant CAD (i.e. one to three arteries with stenosis) more frequently (79.5%) than men with longAR (20.5%); of the subjects with stenosis in no arteries, 56.5% had shortAR and 43.5% longAR (chi2 = 4.3, P = 0.038). This association was independent of age and BMI. The IMT of peripheral arteries, lipid parameters, basal insulin resistance, blood pressure and family history for early CAD, did not differ according to AR length. CONCLUSIONS The shorter CAG repeat of the AR gene is associated with more severe CAD, which suggests a role for the sensitivity to androgens in the increased frequency of CAD in males. In addition, a protective role of endogenous oestrogen, which is higher in the longAR subgroup, can contribute to the observed difference.
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Abstract
Mitral valve prolapse (MVP) has been reported to be associated with systemic lupus erythematosus (SLE). The aim of the present study was to determine the prevalence of MVP in SLE patients, assess its clinical significance and examine the possible association of this entity with other autoimmune indices. Eighty-seven consecutive SLE patients attending the rheumatology clinic and 73 normal control subjects were examined by M-mode, two-dimensional color-Doppler echocardiography. Serum samples were examined for various organ and non-organ specific autoantibodies. MVP was detected in 19/87 patients with SLE and in four of the healthy controls(P = 0.0057). SLE patients with MVP were younger (33.6 +/- 12.4 years) than those without MVP (41. +/- 12.9, P = 0.04) and with shorter duration of the disease (P = 0.03). We found a statistically higher prevalence of anticardiolipin antibodies (aCL) in SLE patients with prolapse (11/19) compared with SLE patients without prolapse (15/68, P = 0.04). This association was independent of age. The aCL-lgG levels were significantly higher in SLE patients with MVP (32.37 +/- 43.26) compared with SLE patients without MVP (22.24 +/- 29.95, P = 0.04). Thyroid autoantibodies tended to be more common in S LE patients with MVP. Th e prevalence of MVP is increased in SLE patients. The presence of aCL and of organ-specific autoantibodies in SLE patients with MVP might indicate the autoimmune origin of MVP. The possibility that SLE patients with MVP may be predisposed to further autoimmune diseases should be considered.
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CD40L overexpression on T cells and monocytes from patients with systemic lupus erythematosus is resistant to calcineurin inhibition. Lupus 2002; 11:370-8. [PMID: 12139375 DOI: 10.1191/0961203302lu211oa] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
To explore the regulatory defects underlying the overexpression of CD40 ligand (CD40L, CD154) in human lupus we studied the effects of cyclosporin-A (CsA), which blocks Ca2+/calcineurin-dependent CD40L gene expression, on peripheral blood-derived T cells and monocytes. In contrast to control subjects, CsA failed to inhibit the prolonged CD40L expression observed in vitro on anti-CD3-activated lupus T cells. Resistance to CsA was not restricted to CD4+ or CD8+ T cell subsets and was disease activity-independent. Experiments assessing the effects of dexamethasone on CD40L expression, as well as of CsA on the early activation marker CD69 expression and on surface CD40L cleavage, confirmed the unique regulation of CD40L in lupus T cells. On the other hand, co-culture with anti-CD3-activated T cells caused surface CD40L expression on monocytes, which was not an Fc receptor-mediated event. Lupus monocytes clearly overexpressed CD40L comparing to healthy and disease-control monocytes, and, similarly to lupus T cells, displayed a prominent resistance to CsA inhibitory effects. These findings indicate that, besides Ca2+/calcineurin-dependent mechanisms, other pathways are involved in the dysregulation of CD40L in SLE immune cells, dissection of which may have important therapeutic implications.
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Density-functional theory studies of acetone and propanal hydrogenation on Pt(111). J Chem Phys 2002. [DOI: 10.1063/1.1471247] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Glucocorticoid effects on myocardial performance in patients with systemic sclerosis. Clin Exp Rheumatol 2001; 19:431-7. [PMID: 11491499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
OBJECTIVE Myocardial inflammation andfibrosis are common autopsyfindings in systemic sclerosis (SSc) and, although symptomatic cardiac involvement occurs less often, current therapies remain empiric and do not prevent or modify its course. In this open, uncontrolled study we assessed the short-term effects of glucocorticoid administration on myocardial performance in patients with SSc in the absence of clinically overt cardiac disease. METHODS Resting radionuclide ventriculography with 99mTc was performed before and 20 days after the administration of prednisolone, 20 mg daily, in 32 patients with SSc without clinically evident myocardial dysfunction at rest; 13 and 19 patients with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA), respectively, were studied in parallel as controls. RESULTS The mean left ventricular ejection fraction (LVEF) value at baseline was 59% in the SSc group; similar values were found for the SLE (61%) and RA (59%) groups. An impaired LVEF (i.e., <50%) was found in 6 patients with SSc and in 1 patient with SLE. Prednisolone administration resulted in a significant percent improvement in the baseline LVEF (mean 18%, p = 0.0001) in the SSc group; this improvement was greater in the patients with diffuse SSc than in those with limited skin disease (27% vs 10%, p = 0.02). The improvement was most prominent in the 6 patients with an initial impaired LVEF No significant improvement was observed in the SLE or RA control groups. The linear trend betveen the individual baseline LVEF values in patients with SSc and their percent changes after treatment (r2 = 0.55, p: 0.00001) showed that the lower the initial LVEF the greater the improvement caused by prednisolone. The degree of LVEF improvement was also associated with the individual erythrocvte sedimentation rate values and serum IgG concentrations at baseline. Prednisolone-induced changes in LVEF were not associated with any changes in blood pressure, heart rate, blood, plasma, or red cell volumes. CONCLUSION Glucocorticoid administration may improve myocardial performance in some patients with SSc. Although further double-blind controlled studies of the long-term effects are warranted, such treatment may be useful in those patients with SSc and documented low LVEF if they are kept under careful observation for objective improvement.
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MESH Headings
- Adolescent
- Adult
- Aged
- Arthritis, Rheumatoid/diagnostic imaging
- Arthritis, Rheumatoid/drug therapy
- Arthritis, Rheumatoid/physiopathology
- Female
- Glucocorticoids/adverse effects
- Heart/diagnostic imaging
- Heart/drug effects
- Heart/physiopathology
- Heart Function Tests
- Humans
- Lupus Erythematosus, Systemic/diagnostic imaging
- Lupus Erythematosus, Systemic/drug therapy
- Lupus Erythematosus, Systemic/physiopathology
- Male
- Middle Aged
- Myocardium
- Prednisolone/adverse effects
- Radionuclide Ventriculography
- Scleroderma, Systemic/diagnostic imaging
- Scleroderma, Systemic/drug therapy
- Scleroderma, Systemic/physiopathology
- Stroke Volume/drug effects
- Ventricular Dysfunction, Left/chemically induced
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Diffusion of N adatoms on the Fe(100) surface. PHYSICAL REVIEW LETTERS 2000; 84:4898-4901. [PMID: 10990826 DOI: 10.1103/physrevlett.84.4898] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2000] [Indexed: 05/23/2023]
Abstract
The diffusion of individual N adatoms on Fe(100) has been studied using scanning tunneling microscopy and ab initio density functional theory (DFT) calculations. The measured diffusion barrier for isolated N adatoms is E(d) = (0.92+/-0.04) eV, with a prefactor of nu(0) = 4.3x10(12) s(-1), which is in quantitative agreement with the DFT calculations. The diffusion is strongly coupled to lattice distortions, and, as a consequence, the presence of other N adatoms introduces an anisotropy in the diffusion. Based on experimentally determined values of the diffusion barriers and adsorbate-adsorbate interactions, the potential energy surface experienced by a N adatom is determined.
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Hemochromatosis associated with endothelial dysfunction: evidence for the role of iron stores in early atherogenesis. Vasc Med 1999; 4:147-8. [PMID: 10512594 DOI: 10.1177/1358836x9900400305] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Impaired endothelium-dependent, flow-mediated dilatation of the brachial artery was observed in a 50-year-old premenopausal female non-smoker with idiopathic hemochromatosis. Endothelial dysfunction observed in this patient supports a relationship between body iron stores and early atherosclerotic process.
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Abstract
A coexistence of mitral valve prolapse (MVP) with autoimmune thyroid disease (AITD) has been described, but there are not sufficient data to explain this association. The aim of the present study was to investigate the prevalence of MVP in patients with AITD and to evaluate whether any correlation between MVP and certain immunological parameters exists. M-mode, two-dimensional Doppler echocardiography was performed in 29 patients with Graves' disease (GD), 35 with Hashimoto's thyroiditis (HT), 20 with nonautoimmune goiter, and 30 normal controls. Serum samples were examined for antinuclear antibodies (ANA), antibodies against extractable nuclear antigen (ENA), antiphospholipid antibodies (aCL), rheumatoid factor (RF), thyroid autoantibodies (TAAb), immunoglobulins and C3, C4. Eight of 29 GD patients and 8 of 35 HT patients had MVP, while none of the control group and 2 of 20 of the simple goiter group had MVP (p < 0.05). ANA were detected at low titers in 5 of 8 in MVP(+) GD versus 3 of 21 in MVP(-) GD (p < 0.05). In the HT group the MVP(+) patients had a significantly higher incidence of ANA and ENA, 5 of 8 and 2 of 8 versus 5 of 27 and 0 of 27 of MVP(-) patients, respectively, p < 0.05. A statistically significant higher incidence of aCL was found in HT MVP(+) patients. (3/8) versus HT MVP(-) 1/27, p < 0.05. RF levels (immunoglobulin A [IgA]) were significantly higher in MVP(+) patients. The association of MVP with nonorgan-specific autoantibodies indicates that MVP may also be an autoimmune disease. It is possible that patients with AITD who also have MVP may be at an increased risk to develop systemic autoimmunity.
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Abstract
Adhesion molecules expressed on the surface of immune cells transduce a variety of cell-activating signals and mediate important interactions by binding to multiple specific counter-receptors expressed on other cells or on extracellular matrix components. A large number of aberrations in the expression of cell-bound molecules at the mRNA and protein level in vivo have been described in patients with autoimmune connective tissue diseases. In vitro studies suggest the presence of functional abnormalities of adhesive pathways, at least at some points of the disease. Increased circulating levels of isoforms of several adhesion molecules have also been demonstrated in these patients. The possible involvement in the pathogenesis of rheumatoid arthritis, systemic lupus erythematosus, Sjögren's syndrome and systemic sclerosis of E-, P- and L-selectins, of some integrins and of several adhesion molecules of the immunoglobulin superfamily that in addition participate in lymphocyte costimulation will be discussed in this review. Further studies on migration and recruitment patterns of immune cells into inflamed tissues, as well as on possible defects of lymphocyte activation in these patients, are expected to expand our knowledge on systemic autoimmune responses and identify targets for specific immunotherapy.
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Hemochromatosis associated with endothelial dysfunction: evidence for the role of iron stores in early atherogenesis. Vasc Med 1999. [DOI: 10.1191/135886399675689098] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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37
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Thyroid disease associated with rheumatoid arthritis is not adequately screened with a sensitive chemiluminescence thyrotrophin assay. ACTA MEDICA AUSTRIACA 1999; 26:26-8. [PMID: 10230473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
The objective of this study was to screen for thyroidopathies in patients with rheumatoid arthritis (RA). Screening for thyroid disorders is advocated in patients with autoimmune diseases, and rheumatoid arthritis has been linked to thyroid autoimmune disorders, more particularly Hashimoto's thyroiditis and sometimes Graves' disease. We performed thyroid disease screening in 69 patients with RA free of medication for at least a 2 weeks period, not in remission, and in 65 patients with osteoarthritis (OA). The latter were studied as a control group of non-autoimmune arthritis patients. Basal levels of thyrotrophin (TSH) were measured using a sensitive chemiluminescence serum TSH assay. Serum antithyroperoxidase and antithyroglobulin (anti-Tg) autoantibodies were measured as well. If TSH values were found to be outside the normal limits, serum total thyroxine, total triiodothyronine (T3), resin T3 uptake, the free thyroxine index (FT4I) and free triiodothyronine index (FT3I) were evaluated. Rheumatoid arthritis patients exhibited statistically significant lower mean TSH values as compared to OA patients. However, RA patients with low TSH values did not have elevated FT4I. Previous use of corticosteroids in some of the RA patients may be responsible for these results. The autoantibodies levels did not differ between the two groups. We conclude that thyroid function screening with sensitive TSH assays is not sufficient for assessment of early stages of autoimmune thyroidopathies in patients with RA. Thyroid hormones should also be estimated.
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Circulating P- and L-selectin and T-lymphocyte activation and patients with autoimmune rheumatic diseases. Clin Rheumatol 1999; 18:28-32. [PMID: 10088945 DOI: 10.1007/s100670050047] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Circulating levels of P- and L-selectins and the degree of T-lymphocyte activation were assessed by enzyme-linked immunosorbent assays in 75 selected patients with rheumatoid arthritis (RA), systemic sclerosis (SSc) and systemic lupus erythematosus (SLE) at various clinical stages, and in 40 healthy blood donors matched for age and gender. Mean levels of P-selectin were significantly higher than normal in RA (lower in patients with clinical remission) and SSc (higher in patients with early-onset diffuse disease), but not in SLE. In contrast, mean L-selectin levels were significantly higher than normal in SLE (no correlation to the degree of disease activity), but not in RA or SSc. Mean levels of soluble interleukin-2 receptors (sIL-2R), reflecting mainly T-lymphocyte activation, in patients with active RA, SSc and SLE were almost double the normal level; however, correlations between individual levels of circulating P- or L-selectins and sIL-2R within groups revealed a strong positive correlation only between L-selectin and sIL-2R (r = 0.66, p<0.001), and only in patients with SLE. Given the different expression of P- and L-selectins, these findings indicate a distinct pattern of immune cell activation in chronic diseases that share an overactivation of T-lymphocytes. The possible clinical value of quantitation of circulating P-selectin in patients with RA and SSc on the one hand, and L-selectin in patients with SLE on the other, should be investigated by prospective studies.
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MESH Headings
- Adult
- Aged
- Arthritis, Rheumatoid/blood
- Arthritis, Rheumatoid/diagnosis
- Arthritis, Rheumatoid/immunology
- Biomarkers/blood
- Cross-Sectional Studies
- Diagnosis, Differential
- Disease Progression
- Enzyme-Linked Immunosorbent Assay
- Female
- Follow-Up Studies
- Humans
- L-Selectin/blood
- Lupus Erythematosus, Systemic/blood
- Lupus Erythematosus, Systemic/diagnosis
- Lupus Erythematosus, Systemic/immunology
- Lymphocyte Activation/immunology
- Male
- Middle Aged
- P-Selectin/blood
- Prognosis
- Prospective Studies
- Reproducibility of Results
- Rheumatic Diseases/blood
- Rheumatic Diseases/diagnosis
- Rheumatic Diseases/immunology
- Scleroderma, Systemic/blood
- Scleroderma, Systemic/diagnosis
- Scleroderma, Systemic/immunology
- T-Lymphocytes/immunology
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Clinical features of juvenile Adamantiades-Behçet's disease in Greece. Clin Exp Rheumatol 1999; 17:256-9. [PMID: 10342057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Adamantiades-Behçet's disease (A-BD) is a chronic relapsing vasculitis of unknown etiology. This disease is relatively rare in children and only recently have series of patients been reported. The objective of this study was to describe the clinical features of the disease in juvenile patients, and to compare them with adult cases and with those juveniles reported in the literature.
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Abstract
In-antimyosin scintigraphy offers a valuable noninvasive method for early detection of clinically silent cardiac involvement in patients with systemic sclerosis, even in the absence of left ventricular dysfunction. In these patients with positive antimyosin study results, intense pharmacologic treatment with vasodilators may be warranted.
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Effect of long-term estrogen therapy on brachial arterial endothelium-dependent vasodilation in women with Raynaud's phenomenon secondary to systemic sclerosis. Am J Cardiol 1998; 82:1555-7, A8. [PMID: 9874070 DOI: 10.1016/s0002-9149(98)00708-5] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Endothelium-dependent and endothelium-independent dilation were reduced in patients with Raynaud's phenomenon secondary to systemic sclerosis. Conjugated estrogen given for 4 weeks significantly improved endothelial function compared with placebo.
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Short-term estrogen administration improves abnormal endothelial function in women with systemic sclerosis and Raynaud's phenomenon. Am Heart J 1998; 136:905-12. [PMID: 9812087 DOI: 10.1016/s0002-8703(98)70137-1] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Morphologic changes of the vascular endothelium are common in patients with systemic sclerosis and Raynaud's phenomenon. The aim of this study was to evaluate the endothelium-dependent vasodilatation and endothelium-independent vasodilatation and to examine the effects of short-term estrogen administration on vascular responses in these patients. METHODS AND RESULTS The study included 12 female patients with systemic sclerosis and Raynaud's phenomenon (aged 49+/-14 years) and 12 age- and sex-matched healthy control subjects. With the use of high-resolution ultrasound imaging, brachial artery diameter was measured at rest, during reactive hyperemia (endothelium-dependent response), and after administration of sublingual nitroglycerin (endothelium-independent dilatation). Intima-media thickness of the common carotid artery was also measured. Baseline diameter was similar in patients and control subjects; intima-media thickness was significantly higher in patients (0.83+/-0.3 vs 0.46+/-0.2 mm, P= .002) than in control subjects. Flow-mediated dilatation was reduced in patients (3.6%+/-7% vs 11.9%+/- 4.6%, P = .003); endothelium-independent dilatation also was reduced in patients with Raynaud's phenomenon (14%+/-7% vs 23%+/-6%, P= .003). Vascular responses in 10 patients were examined 15 minutes after administration of conjugated estrogens (25 mg intravenously); there was a significant increase of endothelium-dependent dilatation after estrogen administration (1.7%+/-4% to 6.3%+/-4%, P= .01), whereas endothelium-independent dilatation did not change (13.4%+/-8% to 15.5%+/-7%, not significant). CONCLUSIONS Endothelium-dependent vasodilatation and endothelium-independent vasodilatation are impaired in patients with Raynaud's phenomenon secondary to systemic sclerosis, whereas intima-media thickness is increased. Short-term estrogen administration can improve endothelial dysfunction in this group of patients.
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Cold-induced coronary Raynaud's phenomenon in patients with systemic sclerosis. Clin Exp Rheumatol 1998; 16:135-40. [PMID: 9536388] [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]
Abstract
OBJECTIVE Cardiac involvement with myocardial-band necrosis is common in systemic sclerosis. One possible explanation is that an underlying vasomotor abnormality accounts for these histologic findings. To shed light on this issue we investigated the existence of "myocardial Raynaud's phenomenon" in such patients. METHODS We examined 25 patients with systemic sclerosis and 14 patients with systemic lupus erythematosus or rheumatoid arthritis, using cold pressor and dipyridamole-thallium-201 scintigraphy. RESULTS Twenty-three patients with systemic sclerosis and 13 patients with lupus erythematosus or rheumatoid arthritis had normal perfusion during dipyridamole imaging. Seven scleroderma patients with normal dipyridamole test presented cold-induced transient myocardial ischemia, while none of the control patients had cold-induced ischemia (p = 0.034). All patients with cold-induced ischemic defects presented long-standing Raynaud's phenomenon (> 5 years); of the 14 patients with long-standing Raynaud's phenomenon 7 presented ischemic thallium-201 defects; of the remaining 9 patients with Raynaud's phenomenon of short duration (< 5 years) none presented cold-induced ischemia (p = 0.019). CONCLUSION Patients with systemic sclerosis and long-standing Raynaud's phenomenon, even in the presence of normal myocardial perfusion during pharmacological vasodilation with dipyridamole, may present cold-induced myocardial ischemia, a functional Raynaud's phenomenon of the heart.
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Effects of 2-chlorodeoxyadenosine and gold sodium thiomalate on human bcl-2 gene expression. Immunopharmacol Immunotoxicol 1998; 20:63-77. [PMID: 9543700 DOI: 10.3109/08923979809034809] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Aberrant expression of apoptosis-related genes, including the "cell death suppressor gene" bcl-2, may play an important pathogenetic role in cancer and autoimmune diseases, In vivo upregulation of bcl-2 mRNA in synovial lining cells of patients with rheumatoid arthritis but not in patients with osteoarthritis has been recently found. In the present study we investigated whether agents exerting beneficial effects in patients with rheumatoid arthritis, namely the long used Gold Sodium Thiomalate (GST) and the novel immunosuppressive, purine analogue 2-chlorodeoxyadenosine (2-CdA), a lymphocyte apoptosis-inducing agent interfere directly with induction of bcl-2 mRNA expression. The phytohemagglutinin (PHA)-induced in vitro proliferation of normal human peripheral blood lymphocytes was significantly inhibited by non-toxic concentrations of 2-CdA and GST which are within the range of in vivo plasma concentrations in patients receiving the respective treatment. Using mRNA dot-blot analysis and hybridization with an IL-2-specific probe we found that GST, similarly to dexamethasone that served as control, suppressed the PHA-induced IL-2 mRNA accumulation dose-dependently. In contrast, 2-CdA (0.1 microgram/ml) at concentrations that inhibit by 80-90% the PHA-induced proliferative responses of lymphocytes did not affect IL-2 mRNA accumulation. Hybridization with a bcl-2-specific probe showed that the activation-induced accumulation and kinetics of bcl-2 mRNA were not changed in the presence of a wide range of concentrations of either GST or 2-CdA. Similarly, the mRNA accumulation of the "house-keeping" control gene beta-action remained unchanged by both agents. These findings indicate that biosynthesis of bcl-2 is not specifically affected by GST and CdA, suggesting that the immunomodulating effects of these agents, including their efficacy in suppressing chronic arthritis, are not related with a bcl-2-dependent mechanism.
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Microfilaremia from a Dirofilaria-like parasite in Greece. Case report. APMIS 1998; 106:315-8. [PMID: 9531965] [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]
Abstract
In Europe, zoonotic filarial infections in humans are caused by two species, Dirofilaria immitis and Dirofilaria repens. These parasites are associated mainly with embolic infarcts of the pulmonary artery and subcutaneous nodules, respectively. An unusual dirofilarial infection in a Greek patient who showed marked eosinophilia and microfilaremia is presented. Although the identification of Dirofilaria species is not conclusive, this report is the first on a case of microfilaremia from a Dirofilaria infection in an immunocompetent patient.
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Density Functional Theory Calculations for Simple Oxametallacycles: Trends across the Periodic Table. J Phys Chem B 1998. [DOI: 10.1021/jp971450p] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Immunocytochemical detection of P-glycoprotein in the management of malignant effusions. J Cancer Res Clin Oncol 1997; 123:456-60. [PMID: 9292710 DOI: 10.1007/bf01372551] [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: 02/05/2023]
Abstract
P-glycoprotein (P-gp), a cell membrane protein, has been found in multidrug-resistant cancer cells. A total of 104 smears from patients with breast-cancer-associated pleural effusions and ovarian-cancer-related peritoneal effusions were studied for P-gp with the antibody C-219 and the avidin-biotin-immunoperoxidase method. Samples were taken before and 3 and 7 days after intracavitary bleomycin therapy and reaccumulation of effusion was assessed at 30 days. Smears that were P-gp-negative by the 7th day were associated with a good 30-day response to bleomycin in the majority of cases, while P-gp-positive smears were associated with a significant reaccumulation of fluid at 30 days. P-gp status is a valuable prognostic indicator of response to intracavitary bleomycin treatment in effusions from breast or ovarian cancer.
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Expression of insulin-like growth factor-I receptor and transferrin receptor by breast cancer cells in pleural effusion smears. Cytopathology 1996; 7:400-5. [PMID: 8958473 DOI: 10.1111/j.1365-2303.1996.tb00545.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Smear preparations were made from cells harvested from pleural fluid from 90 patients with breast cancer and stained for transferrin receptor (TRFr) and insulin-like growth factor-I receptor (IGF-Ir) using an immunocytochemical technique. The results were correlated with those from 36 benign effusions smears. In malignant smears from the breast cancer cases TRFr was demonstrated in 84.4% of the cellular deposits and IGF-Ir in 91.1%. TRFr was demonstrated in two (11%) of the tuberculous effusion smears and in six (100%) effusions from patients with collagen disease. IGF-Ir was not demonstrated in any of the smears from patients with benign disease. The sensitivity and specificity of TRFr staining were 84.4% and 77.7%, respectively, and for IGF-Ir staining were 91.1% and 100%, respectively. The underlying metabolic changes in the tumour cells which give rise to positive staining with these markers are discussed.
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50
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A mean‐field modeling study of the interaction between hydrogen and a palladium (110) single crystal. J Chem Phys 1996. [DOI: 10.1063/1.472694] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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