Determining personalized treatment by gene expression profiling in metastatic breast carcinoma patients: a pilot study

PURPOSE

The present study evaluates the massive study of gene expression in metastatic breast carcinoma (MBC) patients using microarray gene expression profiling (MAGE) complemented with conventional sequencing, immunohistochemistry (IHC) and fluorescent "in situ" hybridization (FISH), seeking to optimize the treatment in a subset of heavily pretreated patients and with limited life expectancy.

PATIENTS, MATERIAL AND METHODS

MBC patients in hormone therapy progression with survival expectancy of at least 3 months (m) have been included. The MAGE contains gene probes representing genes known to potentially interact with available drugs as cited in the literature.

RESULTS

Thirty-nine procedures were performed from October 2010 to April 2016. Within the 30 evaluable procedures, considering all hormonal manipulations as a single line, the patients had received a median of 4 treatment lines prior to MAGE (range 1-7). Progression was observed in 6 cases, stable disease (SD) in 7 cases and partial response (PR) in 16 cases, which implies a clinical benefit rate (SD + PR) of 76%. Actuarial median progression-free survival (PFS) was 6 m (95% CI 2.5-9.5) in patients with clinical benefit. The median overall survival (OS) for the entire series was 11 m (95% CI 2.2-19.8).

CONCLUSION

Data presented here indicate that the use of MAGE provides relevant information to establish personalized treatment in frail patients with limited life expectancy in which therapeutic futility is a particularly difficult burden to assume.

The determination of copeptin levels helps management decisions among transient ischaemic attack patients

BACKGROUND

Most approaches to transient ischaemic attack (TIA) triage use clinical scores and vascular imaging; however, some biomarkers have been suggested to improve the prognosis of TIA patients.

METHODS

Serum levels of copeptin, adiponectin, neopterin, neuron-specific enolase, high-sensitivity C-reactive protein, IL-6, N-terminal pro-B-type natriuretic peptide, S100β, tumour necrosis factor-alpha and IL-1α as well as clinical characteristics were assessed on consecutive TIA patients during the first 24 h of the onset of symptoms.

RESULTS

Among 237 consecutive TIA patients, 12 patients (5%) had a stroke within 7 days and 15 (6%) within 90 days. Among all candidate biomarkers analysed, only copeptin was significantly increased in patients with stroke recurrence (SR) within 7 days (P = 0.026) but not within 90 days. A cut-off point of 13.8 pmol/l was established with a great predictive negative value (97.4%). Large artery atherosclerosis (LAA) [hazard ratio (HR) 12.7, 95% CI 3.2-50.1, P < 0.001] and copeptin levels ≥13.8 pmol/l (HR 3.9, 95% CI 1.01-14.4, P = 0.039) were independent predictors of SR at the 7-day follow-up. LAA was the only predictor of 90-day SR (HR 7.4, 95% CI 2.5-21.6, P < 0.001). ABCD3I was associated with 7- and 90-day SRs (P = 0.025 and P = 0.034, respectively). The association between copeptin levels and LAA had a diagnostic accuracy of 90.3%.

CONCLUSIONS

Serum copeptin could be an important prognostic biomarker to guide management decisions among TIA patients. Therefore, TIA patients with copeptin levels below 13.8 pmol/l and without LAA have an insignificant risk of 7-day SR and could be managed on an outpatient basis.

Parathormone Levels Are Independently Associated with the Presence of Left Ventricular Hypertrophy in Patients with Coronary Artery Disease

BACKGROUND

Abnormalities of mineral metabolism and inflammation may affect the cardiovascular system. We have assessed the relationship of left ventricular hypertrophy (LVH) with inflammation and mineral metabolism.

METHODS

LVH was measured in 146 outpatients with stable coronary artery disease (SCAD) using echocardiography. Calcidiol (a vitamin D metabolite), parathyroid hormone (PTH), fibroblast growth factor-23, high-sensitivity C-reactive protein, MCP-1 (monocyte chemoattractant protein-1), galectin-3, NGAL (neutrophil gelatinase-associated lipocalin), and sTWEAK (soluble TNF-related weak inducer of apoptosis) plasma levels were studied.

RESULTS

LVH, defined as septal thickness ≥11 mm, was present in 19.9% of cases. These patients were older [75.0 (61.0-81.0) vs 64.0 (51.0-76.0) years; p=0.002], had higher prevalence of left ventricular ejection fraction (LVEF)>40%, and had higher PTH [84.7 (59.6-104.7) vs 63.2 (49.2-85.2) pg/ml; p=0.007], galectin-3 [9.6 (8.0-11.1) vs 8.3 (6.9-9.9) ng/ml; p=0.037], and NGAL (208.5±87.6 vs 173.9±73.4 ng/ml; p=0.031) plasma levels than those without LVH. Glomerular filtration rate was lower in patients with LVH than in those without it (65.1±20.0 vs 74.7±19.9 mL/min/1.73 m2; p=0.021). There were no significant differences in hypertension (79.3 vs 68.4%; p=0.363) or sex between both groups. Variables showing differences based on univariate analysis and hypertension were entered into a logistic regression analysis. Only age [odds ratio (OR) =1.052 (1.011-1.096); p=0.013], PTH plasma levels [OR=1.017 (1.003-1.031); p=0.021], and LVEF>40% [OR=7.595 (1.463-39.429); p=0.016] were independent predictors of LVH.

CONCLUSIONS

In patients with SCAD, elevated PTH levels are independently associated with the presence of LVH. Further studies are needed to elucidate the role of PTH in the development of myocardial hypertrophy.

Guidelines for diagnosis, staging and treatment of metastatic colorectal cancer by Grupo Español Multidisciplinar en Cancer Digestivo (GEMCAD)

Abstract 

Advances in the care of patients with metastatic colorectal cancer arise from well-designed clinical trials. In the present document we address specific challenges in the design of clinical trials for metastatic colorectal cancer regarding staging and standard of care according to prognosis, as well as some relevant methodological issues.

N-terminal pro-brain natriuretic peptide level determined at different times identifies transient ischaemic attack patients with atrial fibrillation

BACKGROUND AND PURPOSE

The etiological classification of patients with transient ischaemic attack (TIA) is a difficult endeavor and the use of serum biomarkers could improve the diagnostic accuracy. The aim of this study was to correlate atrial fibrillation, the main cardioembolic etiology (CE), with different serum biomarkers measured in consecutive TIA patients.

METHODS

The concentrations of interleukin-6 (IL-6), tumor necrosis factor-alpha, neuron-specific enolase, high-sensitivity C-reactive protein, IL-1-α and the N-terminal pro-B type natriuretic peptide (NT-proBNP) were quantified in the serum of 140 patients with TIA and 44 non-stroke subjects. Measurements were performed at different times throughout evolution: within 24 h of symptoms onset and at days 7 and 90.

RESULTS

With the exception of IL-6, all biomarkers were higher in TIA patients than in controls. NT-proBNP was significantly related to the presence or new diagnosis of AF at all time points analyzed. Furthermore, the baseline NT-proBNP level was significantly higher than values at the 7-day and 90-day follow-up. For this reason, different cut-off values were obtained at different times: 313 pg/ml at baseline [odds ratio (OR) = 18.99, P < 0.001], 181 pg/ml at 7 days (OR = 11.4, P = 0.001) and 174 pg/ml (OR = 8.46, P < 0.001) at 90 days.

CONCLUSION

High levels of NT-proBNP determined during the first 3 months after a TIA were associated with AF. Consequently, this biomarker may be useful to reclassify undetermined TIA patients as having disease of CE.

Treatment of advanced non-small cell lung cancer (NSCLC) with a biweekly schedule of irinotecan (I), paclitaxel, and cisplatinum (P): A phase II study

e19076

Background: Irinotecan, paclitaxel (taxol, T), and cisplatinum are among the most active agents in the treatment of NSCLC, given alone as single agents or in combination. Based in previous data (Proc ASCO 2003 # 2816), we performed a confirmatory phase II study of the activity of a bi-weekly combination of I (120 mg/m2), T(60 mg/m2) and P (40 mg/m2) in advanced NSCLC. Methods: Forty-three patients (pts) (37 male, 6 female) with histologically proven IIIA-IV NSCLC were treated at our institution. Median age was 61 years (33–79). All pts were ECOG 0–2. 14 pts had locally advanced disease (8 IIIA, 6 IIIB) and 29 metastatic disease. Previous treatments included surgery (5 pts), radiotherapy (4 pts), chemotherapy (5 pts), surgery + radiotherapy (3 pts) and surgery + chemotherapy (2 pt). In three cases, treatment was administered as adjuvant after resection of a primary (2 cases) or a metastatic tumor (1 case). Results: A total of 299 courses were administered (median 6, range 2–14). Toxic episodes grade III-IV were neutropenic fever (10/299; 3.3%), anemia (1/299; 0.3%), asthenia (3/299; 1%), diarrhea (5/299; 17%), hemorrhagic colitis (1/299; 0.3%), mucositis (2/299, 0.6%), vomiting (4/299; 1.3%) and peripheral neuropathy (1/299; 0.3%). With a median follow-up of 72 months (9–97), 2 pts (4.6%) presented pathological complete response, 26 (60%) partial response, 11 (25%) stable disease and 1 pt progressed. Four partial responders were rendered free of disease after rescue surgery. Median time to progression was 6 months. Median survival was 10 months. The actuarial 2 and 5-year overall survival are 26% and 13% respectively. Conclusions: I, T and P at the referred doses can be safely administered in a bi-weekly basis, with a good tolerance and response rate in advanced NSCLC pts.

No significant financial relationships to disclose.

Umbilical cord blood-derived stem cells spontaneously express cardiomyogenic traits

BACKGROUND

Umbilical cord blood (UCB) has been widely used for hematopoietic stem cell transplantation. The UCB-derived stem cells (UCBSCs) have been proposed as an alternative to bone marrow (BM)-derived mesenchymal stem cells (MSCs) for cardiac cell-based therapy. Herein we studied whether UCBSCs spontaneously exhibit cardiac-specific markers in vitro.

METHODS

Human UCBSCs were isolated, expanded, and phenotyped by flow cytometry, quantitative RT-PCR, and immunofluorescence. Cell pluripotency and proliferation were also assessed by adipogenic and osteogenic media and in growth assays.

RESULTS

Among 25 analyzed UCB, 16% of cases afforded primary culture satisfactory generation of UCBSCs. Duplication time (Td) of cultures was 2.16 +/- 0.06 days. The cells were strongly positive for CD105 (18.5 +/- 0.14), CD44 (27 +/- 2.8), CD166 (13 +/- 9), CD29 (59 +/- 9.4), CD90 (60 +/- 11) and consistently negative for CD117 (1.2 +/- 0.1), CD106 (1.1 +/- 0), CD34 (1.2 +/- 0.2), CD14 (1 +/- 0), and CD45 (1 +/- 0), consistent with a mesenchymal lineage. Adipogenesis and osteogenesis of cells resulted in low accumulation of intracellular lipid droplets and high deposition of calcium. The UCBSCs showed gene transcripts for alpha-actinin, connexin (Cx)-43, SERCA-2, and stromal cell-derived factor (SDF)-1alpha. At the protein level, the cells abundantly expressed alpha-actinin, Cx-43, SERCA-2 and SDF-1alpha. In contrast, these cells did not express the cardiac transcription factors GATA-4, Tbx5, and Nkx2.5, nor the sarcomeric proteins beta-myosin heavy chain (beta-MyHC) or cardiac troponin I (cTnI).

CONCLUSIONS

Human UCBSCs may represent an alternative source of stem cells for myocardial-cell replacement. These cells can be highly expanded. They spontaneously express proteins of paramount importance for cardiovascular regeneration, such as Cx-43, SERCA-2, and SDF-1alpha.

Infections of implantable cardioverter-defibrillators: frequency, predisposing factors and clinical significance

The prognosis for patients with ventricular arrhythmias has improved dramatically with the aid of implantable cardioverter-defibrillators (ICDs). Although infection is a serious complication that frequently causes dysfunction and loss of ICDs, the frequency, predisposing risk-factors, and clinical and microbiological features are only partially understood. This study describes a retrospective review of 423 procedures in 278 patients with ICD primary implants and replacements performed at a tertiary-care hospital. Generators were placed in either a pectoral (68%) or abdominal (32%) site, and electrodes were placed transvenously in 97% of the patients. Most (95%) interventions were performed in a one-stage procedure. Infection developed with ten (2.4%) implanted devices. Four cases occurred within 30 days of surgery ('early infections') and six occurred > 1 month after surgery ('late infections'). In univariate analysis, factors associated with the development of an early infection were: two-stage surgery, a sub-costal approach, and abdominal generator placement. In patients with late infections, a significant association was found with trauma or decubitus ulcer in the generator area. Infection presented with local signs without systemic complications. Seven of the ten patients required complete removal of the system.

Identification of cardiomyogenic lineage markers in untreated human bone marrow-derived mesenchymal stem cells

BACKGROUND

Recent reports refute the classic paradigm by which human heart is unable to repair itself following disease or injury. Cardiac and noncardiac stem cells with cardiac regeneration potential have been documented. We studied whether untreated mesenchymal stem cells express markers of cardiomyogenic lineage in vitro.

METHODS

Mesenchymal stem cells were obtained from human iliac crest marrow aspirates. Cells were isolated and characterized using flow cytometry by surface expression of CD105, CD166, CD29, CD44, CD14, and CD34. To evaluate their cardiomyogenic potential, presence of cardiac proteins (cardiac troponin I, sarcomeric alpha-actinin, beta myosin heavy chain (beta-MyHC), connexin-43, and SERCA-2), and transcription factors (GATA-4) were assessed.

RESULTS

Mesenchymal stem cells expressed CD105 (4.25 +/- 0.35), CD166 (27.83 +/- 1.89), and CD29 (9.4 +/- 0.57) and were negative for CD34, CD14, and CD45. In absence of additional stimuli in the culture media, these cells expressed connexin-43, alpha-actinin, and GATA-4, and were negative for SERCA-2, cardiac troponin I, and beta-MyHC.

CONCLUSIONS

Human adult mesenchymal stem cells spontaneously exhibit markers of cardiac phenotype in vitro. In the appropiate myocardial environment, these cells may transdifferentiate into mature cardiomyocytes.

Sinus node revisited in the era of electroanatomical mapping and catheter ablation

OBJECTIVE

To study the architecture of the human sinus node to facilitate understanding of mapping and ablative procedures in its vicinity.

METHODS

The sinoatrial region was examined in 47 randomly selected adult human hearts by histological analysis and scanning electron microscopy.

RESULTS

The sinus node, crescent-like in shape, and 13.5 (2.5) mm long, was not insulated by a sheath of fibrous tissue. Its margins were irregular, with multiple radiations interdigitating with ordinary atrial myocardium. The distances from the node to endocardium and epicardium were variable. In 72% of the hearts, the whole nodal body was subepicardial and in 13 specimens (28%) the inner aspect of the nodal body was subendocardial. The nodal body cranial to the sinus nodal artery was more subendocardial than the remaining nodal portion, which was separated from the endocardium by the terminal crest. In 50% of hearts, the most caudal boundaries of the body of the node were at least 3.5 mm from the endocardium. When the terminal crest was > 7 mm thick (13 hearts, 28%), the tail was subepicardial or intramyocardial and at least 3 mm from the endocardium.

CONCLUSIONS

The length of the node, the absence of an insulating sheath, the presence of nodal radiations, and caudal fragments offer a potential for multiple breakthroughs of the nodal wavefront. The very extensive location of the nodal tissue, the cooling effect of the nodal artery, and the interposing thick terminal crest caudal to this artery have implications for nodal ablation or modification with endocardial catheter techniques.

[Anatomy of the atria for rhythmologists]

The anatomy of the atria is always in the mind of interventional rhythmologists. There is a mental superposition of the anatomical structures and the references obtained by different incidences of fluoroscopy and the endocavitary electrocardiogram. But understanding the anatomy also requires a certain knowledge of dissection to determine, for example, the orientation of bundles of muscle fibres and anatomical sections. The sino-atrial node is situated at a distance from the endocardium. It is long and protected by its own artery which makes it difficult to reach. The atrio-ventricular node has multiple posterior expansions which correspond to the sites where radiofrequency ablation is effective. The cavo-tricuspid isthmus is the target zone for the treatment of atrial flutter but radiofrequency ablation which must be long may be applied at three different levels: inferolateral, median (the most common site) or inferoseptal. Finally, atrial fibrillation has incited many studies of the muscular extensions of the left atrium to the pulmonary veins, the morphological variations of these veins and the organisation of the muscle fibres of the left atrial wall. They have inspired new concepts of atrial fibrillation.

Prior aspirin use in unstable angina patients with modified plasma inflammatory markers and endothelial nitric oxide synthase in neutrophils

BACKGROUND

Prior use of aspirin in patients with acute coronary syndrome has been associated with a lower incidence of acute myocardial infarction. The aim of this study was to explore if prior aspirin therapy in unstable angina (UA) patients could modify systemic inflammatory markers such as interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-alpha) and intercellular adhesion molecule-1 (ICAM-1) and the expression of endothelial nitric oxide synthase (eNOS) in neutrophils.

MATERIALS AND METHODS

Unstable angina was defined as transient S-T segment changes without significant increases in CK and CK-MB. We studied 50 consecutive patients admitted to hospital within 24 h after the onset of chest pain. The number of patients with prior aspirin was significantly higher (n = 32) than those not taking aspirin (n = 18) on admission.

RESULTS

Plasma levels of IL-6 and ICAM-1 were significantly increased in the UA patients when compared with the healthy control volunteers (n = 20) used as a reference for normal values. Plasma levels of both IL-6 and ICAM-1 were reduced in patients taking aspirin. There were no differences in the plasma levels of TNF-alpha between the UA patients and the control volunteers. The eNOS protein expression was also higher in neutrophils from the UA patients taking aspirin than in those not taking aspirin.

CONCLUSION

Patients taking aspirin before UA showed a lower systemic inflammatory response and higher eNOS protein expression in their neutrophils

The terminal crest: morphological features relevant to electrophysiology

OBJECTIVE

To investigate the detailed anatomy of the terminal crest (crista terminalis) and its junctional regions with the pectinate muscles and intercaval area to provide the yardstick for structural normality.

DESIGN

97 human necropsy hearts were studied from patients who were not known to have medical histories of atrial arrhythmias. The dimensions of the terminal crest were measured in width and thickness from epicardium to endocardium, at the four points known to be chosen as sites of ablation.

RESULTS

The pectinate muscles originating from the crest and extending along the wall of the appendage towards the vestibule of the tricuspid valve had a non-uniform trabecular pattern in 80% of hearts. Fine structure of the terminal crest studied using light and scanning electron microscopy consisted of much thicker and more numerous fibrous sheaths of endomysium with increasing age of the patient. 36 specimens of 45 (80%) specimens studied by electron microscopy had a predominantly uniform longitudinal arrangement of myocardial fibres within the terminal crest. In contrast, in all specimens, the junctional areas of the terminal crest with the pectinate muscles and with the intercaval area had crossing and non-uniform architecture of myofibres.

CONCLUSIONS

The normal anatomy of the muscle fibres and connective tissue in the junctional area of the terminal crest/pectinate muscles and terminal crest/intercaval bundle favours non-uniform anisotropic properties.

Regulation of endothelial nitric oxide synthase expression in the vascular wall and in mononuclear cells from hypercholesterolemic rabbits

BACKGROUND

We recently obtained evidence demonstrating that cultured bovine endothelial cells contain cytosolic proteins that form complexes with the 3'-untranslated region of endothelial nitric oxide synthase (eNOS) mRNA and are associated with its destabilization. The aim of this study was to determine the presence of such proteins and eNOS expression in hypercholesterolemic rabbits as an in vivo model of endothelial dysfunction.

METHODS AND RESULTS

Endothelium-dependent relaxation to acetylcholine and the calcium ionophore A23187 was reduced in aortic segments from hypercholesterolemic rabbits compared with controls. Treatment of hypercholesterolemic rabbits with cerivastatin (0.1 mg. kg body wt(-1). d(-1)) restored endothelium-dependent relaxation. Aortic eNOS expression was reduced in hypercholesterolemic rabbits and was accompanied by enhanced binding activity of a 60-kDa cytosolic protein and reduced stability of eNOS mRNA. Cerivastatin treatment upregulated eNOS expression and reduced the interaction of the cytosolic protein with the 3'-untranslated region of eNOS mRNA. Mononuclear cells from hypercholesterolemic rabbits also showed a marked reduction of eNOS expression and eNOS mRNA stability and an increase in binding activity of the cytosolic protein, which were also prevented by cerivastatin treatment.

CONCLUSIONS

These results demonstrate the presence of a 60-kDa protein that binds to eNOS mRNA and reductions in eNOS expression in both vascular wall and mononuclear cells that are prevented by cerivastatin.

Architecture of the pulmonary veins: relevance to radiofrequency ablation

BACKGROUND

Radiofrequency ablation of tissues in pulmonary veins can eliminate paroxysmal atrial fibrillation.

OBJECTIVE

To explore the characteristics of normal pulmonary veins so as to provide more information relevant to radiofrequency ablation.

METHODS

20 structurally normal heart specimens were examined grossly. Histological sections were made from 65 pulmonary veins.

RESULTS

The longest myocardial sleeves were found in the superior veins. The sleeves were thickest at the venoatrial junction in the left superior pulmonary veins. For the superior veins, the sleeves were thickest along the inferior walls and thinnest superiorly. The sleeves were composed mainly of circularly or spirally oriented bundles of myocytes with additional bundles that were longitudinally or obliquely oriented, sometimes forming mesh-like arrangements. Fibrotic changes estimated at between 5% and 70% across three transverse sections were seen in 17 veins that were from individuals aged 30 to 72 years.

CONCLUSIONS

The myocardial architecture in normal pulmonary veins is highly variable. The complex arrangement, stretch, and increase in fibrosis may produce greater non-uniform anisotropic properties.

[Doxazosin and soluble guanylate cyclase in a rat model of hypertension]

BACKGROUND

Although different studies have evaluated the ability of endothelial cells to produce NO in the setting of the endothelial dysfunction associated with hypertension, less it is known about the soluble guanylate cyclase system.

AIM

To analyze the level of expression of sGC in the vascular wall in Stroke-prone spontaneously hypertensive rats (SHRSP). Moreover, the effect of treatment with an alpha1 adrenergic antagonist, doxazosin, on sGC expression was also evaluated.

METHODS

The study was performed in 24 untreated 20-week-old SPSHR and 12 SPSHR treated orally with doxazosin (10 mg/Kg bw/day; for 15 days). A group of normotensive Wistar-Kyoto (WKY) rats were used as controls (n = 12).

RESULTS

Isolated aortic segments from SHRSP showed impaired response to SNP. Doxazosin treatment prevented impaired vasodilatory response to SNP. Expression of the beta1 sGC in the vascular wall of SHRSP determined by Western blot and immunohistochemistry was markedly reduced with respect to that of WKY. Doxazosin treatment increased of beta1 sGC expression in treated SHRSP particularly at the medium level with respect to that of untreated SHRSP.

CONCLUSION

SHRSP showed reduced expression of beta1 sGC in the vascular wall and an impaired vasodilator response to SNP which improved with doxazosin treatment. These results suggest the role the sGC system may play in the global treatment of endothelial dysfunction.

[Guidelines of the Spanish Society of Cardiology on requirements and equipment in electrophysiology]

Due to the enormous qualitative and quantitative evolution that clinical electrophysiology has experienced over the past years, specific Units dedicated to the management of patients with cardiac arrhythmias have been created. In these guidelines, the minimum technical and human needs of an Arrhythmia Unit are discussed.

Inhibition of platelet activation in stroke-prone spontaneously hypertensive rats: comparison of losartan, candesartan, and valsartan

In vitro studies have suggested that losartan interacts with the thromboxane (TxA2)/ prostaglandin H2 (PGH2) receptor in human platelets, reducing TxA2-dependent platelet activation. The aim of this study was to evaluate the effect of different angiotensin II type 1 receptor antagonists in stroke-prone spontaneously hypertensive rats (SHRSP). The level of platelet activation was assessed by determining P-selectin expression in platelets by flow cytometry. The ex vivo adhesion of platelets was also analyzed. The number of platelets that expressed P-selectin in SPSHR was significantly increased (% P-selectin expression: WKY 4 +/- 0, 4%; SHRSP 15.5 +/- 0, 8% [n = 8], p < 0.05). In SHRSP receiving losartan (20 mg/kg body weight per day) the percentage of platelets expressing P-selectin fell to levels close to that observed in WKY. The number of platelets from SHRSP treated with valsartan and candesartan (20 mg/kg body weight per day for 14 days) that expressed P-selectin was not significantly different from those from untreated SPRHR. Only losartan treatment reduced ex vivo platelet adhesion to a synthetic surface. The antiplatelet effect of losartan does not appear to be related to the level of blood pressure reduction. In ex vivo experiments, losartan significantly reduced the binding of the radiolabeled TxA2 agonist U46619 to platelets obtained from SHRSP in a dose-dependent manner. Treatment with losartan reduced the number of activated platelets in SHRSP independently of its blood pressure effects. TxA2-receptor blockade is proposed as a mechanism by which losartan can prevent platelet activation.

Cerivastatin prevents tumor necrosis factor-alpha-induced downregulation of endothelial nitric oxide synthase: role of endothelial cytosolic proteins

Cardiovascular disease is accompanied by an impaired endothelium-dependent vasodilatory response. Loss of endothelial nitric oxide synthase (eNOS) expression may contribute to endothelial dysfunction. The aim of the present study was to analyze the effect of cerivastatin, a novel HMG CoA reductase inhibitor, on tumor necrosis factor-alpha (TNF-alpha)-induced downregulation of eNOS protein expression in bovine aortic endothelial cells (BAEC). TNF-alpha (10 ng/ml)- incubated BAEC showed a reduced expression of eNOS protein and decreased eNOS mRNA stabilization. This effect was associated with an increased binding activity of BAEC cytosolic proteins to the 3'-untranslated region (3'UTR) of eNOS mRNA. Cerivastatin prevented TNF-alpha-induced downregulation of eNOS protein expression in a concentration-dependent manner (10(-8) to 10(-5) M). Cerivastatin also prevented the binding of the cytosolic proteins to 3'-UTR of eNOS mRNA and was associated with eNOS mRNA stabilization. The reduced expression of eNOS protein by TNF-alpha was also prevented by coincubation with cycloheximide. In addition cycloheximide inhibited the binding activity of the cytosolic proteins to 3'-UTR of eNOS mRNA, suggesting the inducible character of the mentioned-cytosolic proteins. TNF-alpha stimulated the translocation of nuclear factor-kappaB (NF-kappaB), an effect that was not modified by cerivastatin. Furthermore, an inhibitor of NF-kappaB translocation, pyrrolidine dithiocarbamate failed to modify both the downregulation of eNOS expression and the increased binding activity of the cytosolic proteins to 3'-UTR of eNOS mRNA by TNF-alpha. The effect of cerivastatin on eNOS expression and the binding activity of the cytosolic proteins were reversed by coincubation with L-mevalonate. In conclusion, cerivastatin stabilized eNOS mRNA and upregulated eNOS expression in the endothelium, and this was associated with a decreased binding activity of cytosolic proteins to 3'-UTR of eNOS mRNA. The effect of cerivastatin on the regulation of eNOS expression was independent of NF-kappaB mobilization by TNF-alpha. These findings suggest that cerivastatin may have beneficial effects on the endothelial dysfunction associated with cardiovascular diseases beyond its effect on lowering cholesterol.

Expression of an endothelial-type nitric oxide synthase isoform in human neutrophils: modification by tumor necrosis factor-alpha and during acute myocardial infarction

OBJECTIVES

The purpose of this study was to determine whether human neutrophils express an endothelial-type nitric oxide synthase (eNOS), and to study the effect of tumor necrosis factor-alpha (TNF-alpha) on its expression.

BACKGROUND

Several studies have demonstrated the presence of a constitutively expressed nitric oxide svnthase (NOS) in neutrophils. Cardiovascular disease is characterized by increased levels of plasma TNF-alpha, a cytokine that has demonstrated eNOS messenger ribonucleic acid (mRNA) destabilization in cultured endothelial cells.

METHODS

Neutrophils were obtained from healthy volunteers and from patients with acute myocardial infarction (AMI).

RESULTS

Human neutrophils express eNOS mRNA and eNOS protein. Stimulation of neutrophils with TNF-alpha decreased eNOS protein expression by reducing eNOS mRNA stabilization. In the present study, we also show that the cytosol of human neutrophils contains proteins that bind to a specific region within the 3'-untranslated region (3'-UTR) of eNOS mRNA. Tumor necrosis factor-alpha increased the binding of the cytosolic proteins to the 3'-UTR of eNOS mRNA. Simvastatin reduced the TNF-alpha-related binding activity of neutrophil cytosolic proteins to eNOS mRNA, which was associated with its protective effect on eNOS protein expression. The in vivo reproduction of the in vitro findings was performed in neutrophils obtained from patients with AMI and showed a diminished expression of eNOS protein, which was associated with increased binding of the cytosolic proteins.

CONCLUSIONS

These observations demonstrate that human neutrophils express eNOS, which is downregulated by TNF-alpha and during AMI. This effect is associated with increased binding of neutrophil cytosolic proteins to the 3'-UTR of eNOS mRNA.

Topographic anatomy of the inferior pyramidal space: relevance to radiofrequency catheter ablation

INTRODUCTION

Radiofrequency catheter ablation carried out in the vicinity of the triangle of Koch risks damaging not only the AV conduction tissues but also their arterial supply. The aim of this study was to examine the relationship of the AV nodal artery to the inferior pyramidal space, the triangle of Koch, and the right atrial endocardial surface.

METHODS AND RESULTS

We studied 41 heart specimens, 24 by gross dissections and 17 by histologic sections. The proximity of the AV nodal artery to the surface landmarks of the triangle of Koch was variable, but it was notable that in 75% of specimens the artery passed close to the endocardial surface of the right atrium and within 0.5 to 5 mm of the mouth of the coronary sinus. In all specimens, the mean distance of the artery to the endocardial surface was 3.5 +/- 1.5 mm at the base of Koch's triangle. The location of the compact AV node and its inferior extensions varied within the landmarks of the triangle. At the mid-level of Koch's triangle, the compact node was medially situated in 82% of specimens, but it was closer to the hinge of the tricuspid valve in the remaining 18% of specimens. In 12% of specimens, the inferior parts of the node extended to the level of the mouth of the coronary sinus.

CONCLUSION

The nodal artery runs close to the orifice of the coronary sinus, the endocardial surface of the right atrium, the middle cardiac vein, and the specialized conduction tissues in most hearts. The nodal artery and/or the AV conduction tissues can be at risk of damage when ablative procedures are carried out at the base of the triangle of Koch.

Therapeutic decision tree for patients with sustained ventricular tachyarrhythmias or aborted cardiac arrest: a critical review of the Antiarrhythmics Versus Implantable Defibrillator trial and the Canadian Implantable Defibrillator Study

Antiarrhythmic drugs, mainly amiodarone and sotalol, radiofrequency catheter ablation, and the implantable cardioverter defibrillator (ICD) are the 3 therapeutic options in patients with sustained ventricular tachycardia (VT) or ventricular fibrillation (VF). Idiopathic VT, incessant VT, frequently recurring, hemodynamically stable VT, and VT based on bundle branch reentry, are candidates for radiofrequency catheter ablation. Patients with high-risk ventricular tachyarrhythmias should receive ICDs as initial therapy. Two studies, the Antiarrhythmics Versus Implantable Defibrillator trial (AVID) and the Canadian Implantable Defibrillator Study (CIDS) have tried to approach the problem of these high-risk ventricular tachyarrhythmias. Although at 3 years, the ICD in AVID demonstrated a significant relative risk reduction over amiodarone of 31.5%, CIDS could not duplicate this finding. At 3 years, the relative risk reduction conferred by the ICD over amiodarone in CIDS was only 13.7%. A careful analysis of both studies suggests that CIDS was insufficiently powered to demonstrate statistically significant benefits similar to those shown by AVID, and furthermore, seemed to include an undetermined number of low-risk VT patients. The problem in the CIDS trial in this regard was the recruitment of patients in whom the inclusion criteria were met by the arrhythmias induced during the electrophysiology stimulation study, but which did not exist in real life. In addition CIDS included 14% of patients with (1) undocumented syncope and inducible monomorphic sustained VT; or (2) long runs of spontaneous nonsustained VT. Under these circumstances, the therapeutic implications of AVID remain unchallenged.

A 4-trifluoromethyl derivative of salicylate, triflusal, stimulates nitric oxide production by human neutrophils: role in platelet function

BACKGROUND

The thrombotic process is a multicellular phenomenon in which not only platelets but also neutrophils are involved. Recent in vitro studies performed in our laboratory have demonstrated that triflusal, a 4-trifluoromethyl derivative of salicylate, reduced platelet aggregation not only by inhibiting thromboxane A2 production but also by stimulating nitric oxide (NO) generation by neutrophils. The aim of the present study was to evaluate whether oral treatment of healthy volunteers with triflusal could modify the ability of their neutrophils to produce NO and to test the role of the NO released by neutrophils in the modulation of ADP-induced platelet aggregation and alpha-granule secretion.

METHODS

The study was performed in 12 healthy volunteers who were orally treated with triflusal (600 mg day-1) for 5 days. Flow cytometric detection of platelet surface expression of P-selectin was used as a measure of the ability of platelets to release the contents of their alpha-granules.

RESULTS

After treatment with triflusal, there was an increase in NO production by neutrophils and an increase in endothelial nitric oxide synthase (eNOS) protein expression in neutrophils. A potentiation of the inhibition of platelet aggregation by neutrophils was reversed by incubating neutrophils with both an L-arginine antagonist, NG-nitro-L-arginine methyl ester (L-NAME) and an NO scavenger, 2-(4-carboxyphenyl)-4,4,5,5 tetramethylimidazoline 1-oxyl 3-oxide (C-PTIO). A slight decrease in P-selectin surface expression on platelets was found which was not modified by the presence of neutrophils and therefore by the neutrophil-derived NO. Exogenous NO released by sodium nitroprusside dose-dependently inhibited both ADP-stimulated alpha-granule secretion and platelet aggregation. Therefore, platelet aggregation showed a greater sensitivity to be inhibited by exogenous NO than P-selectin expression.

CONCLUSION

Oral treatment of healthy volunteers with triflusal stimulated NO production and eNOS protein expression in their neutrophils. After triflusal treatment, the neutrophils demonstrated a higher ability to prevent ADP-induced platelet aggregation. However, the neutrophils and the endogenous NO generated by them failed to modify P-selectin expression in ADP-activated platelets.

Comparative effects of angiotensin II AT-1-type receptor antagonists in vitro on human platelet activation

A recent study has shown that losartan, an AT-1-receptor antagonist, interacts with thromboxane A2 (TxA2)/prostaglandin H2 (PGH2) receptors in human platelets. The aim of this study was to analyze the ability of different angiotensin II (Ang II) AT-1-receptor antagonists to inhibit TxA2-dependent human platelet activation. Platelets were obtained from healthy volunteers. Platelets were stimulated with the TxA2 analogue, U46619 (10(-6) M). U46619-stimulated platelet activation was significantly reduced by both losartan and irbesartan in a dose-dependent manner. Only maximal doses of valsartan (5 x 10(-6) M) and the main metabolite of losartan, EXP3174 (5 x 10(-6) M), reduced U46619-induced platelet activation. Whereas the active form of candesartan cilexetil (candesartan, CV-11974) failed to modify platelet activation involved by TxA2, telmisartan showed a higher effect than valsartan and EXP3174 but lower than either losartan and irbesartan. Losartan or irbesartan reduced the binding of [3H]-U46619 to platelets, an effect that was observed with lower ability with the other AT-1 antagonists. Although platelets expressed AT-1-type receptors, exogenous Ang II did not modify platelet activation. This effect was not modified by blocking the AT-2 receptor with PD123319. These results suggest that some AT-1-receptor antagonists reduce TxA2-dependent activation independent of Ang II involvement.

[Effect of losartan on human platelet activation by thromboxane A2]

INTRODUCTION AND OBJECTIVES

Previous studies have demonstrated that losartan, an AT-1 receptor antagonist of angiotensin II (Ang II) could block the receptor of thromboxane A2 (TXA2) in the vascular wall. The aim of the present study was to assess the effect of losartan on human platelet activation.

MATERIALS AND METHODS

Platelets were obtained from 15 healthy men between the age 26 and 40. Platelet activation was measured by changes in the light transmission of platelet-rich plasma stimulated by a synthetic TXA2 analogue, U46619 (5 x 10(-6) mol/l).

RESULTS

The U46619-stimulated platelet aggregation was significantly inhibited by losartan in a dose-response manner. Only a high dose of EXP 3174 (5 10-5 mol/l), the in vivo active metabolite of losartan, was able to attenuate U46619-induced platelet activation. Captopril, an angiotensin I-converting inhibitor failed to modify U46619-induced platelet aggregation. Despite the platelets expressing AT-1 type receptors, of Ang II exogenous Ang II did not modify platelet aggregation induced by U46619. The binding of U46619 to platelets was competitively inhibited by losartan in dose-dependent manner. However, only a high dose of EXP 3174 reduced the binding of U46619. Captopril failed to modify the binding of U46619 to platelets.

CONCLUSIONS

Losartan decreased platelet aggregation by a TXA2-dependent mechanism. EXP 3174 showed a lesser potency than losartan to reduce TXA2-platelet activation. Captopril and exogenous angiotensin II had no effect on human platelet activation. These results suggest that losartan reduced TXA2-dependent platelet activation independently of the blockade of AT-1 receptors.

Doxazosin modifies Bcl-2 and Bax protein expression in the left ventricle of spontaneously hypertensive rats

BACKGROUND

Increased apoptosis has recently been reported in the heart of spontaneously hypertensive rats (SHRs).

OBJECTIVE

To investigate the molecular basis of apoptosis in the left ventricle of SHRs in terms of the expression of Bcl-2 protein (which protects from apoptosis) and Bax protein (which acts as an apoptotic promoter). In addition, we analysed the involvement of alpha -adrenergic receptors in the left ventricular apoptosis of SHRs.

METHODS

The study was performed in untreated SHRs (n=16) and SHRs that were orally treated with doxazosin (10 mg/kg body weight per day, for 15 days), a selective alpha1-receptor blocker (n=16). A group of Wistar-Kyoto (WKY) rats (n=16) was used as the control.

RESULTS

The left ventricles of untreated SHRs showed a significant increase in Bcl-2 protein expression and a reduced presence of Bax protein. The ratio of Bcl-2:Bax in SHRs was higher than in WKY rats, suggesting an anti-apoptotic state. Paradoxically, both the number of apoptotic cardiac cells and the cleavage of an 85-kDa fragment of the poly (ADP-ribose) polymerase (PARP), a marker of caspase-3 activity, were higher in the left ventricle of SHRs than in WKY rats, suggesting an apoptotic situation. Bax promotes cell apoptosis when it is bound to Bcl-2. We then determined the abundance of Bax-Bcl-2 complexes in the left ventricle of the two groups of animals. Bax-Bcl-2 complexes were more abundant in SHRs than WKY rats. In a second set of experiments, we analysed the role of alpha1-adrenergic blockade by doxazosin in the above-described mechanisms. Doxazosin treatment reduced the formation of Bax-Bcl-2 complexes in the left ventricle of SHRs, and this was accompanied by a decrease in the levels of 85kDa PARP and a reduction in apoptotic left ventricular cells.

CONCLUSIONS

The present work suggests that the presence of Bax-Bcl-2 complexes in the left ventricle could be a more reliable marker of the apoptotic state than the determination of the absolute expression of Bcl-2 and Bax proteins. Moreover, the inhibition of alpha1 -adrenergic receptors by doxazosin decreased the abundance of BaxBcl-2 complexes and promoted a reduction of apoptosis in the left ventricle of SHRs.

[The effect of triflusal on human platelet aggregation and secretion: the role of nitric oxide]

INTRODUCTION AND AIMS

The thrombotic process is a multicellular phenomenon in which not only platelets are involved but also neutrophils are involved. Recent in vitro studies performed in our laboratory have demonstrated that triflusal reduced platelet aggregation by stimulating nitric oxide (NO) production by neutrophils. The aim of the present study was to evaluate whether the in vivo treatment with triflusal could also modify the ability of neutrophils to produce NO. Furthermore, the role of NO released by neutrophils on platelet aggregation and secretion was also tested.

METHODS

The study was performed in 12 healthy volunteers of 32 +/- 6 years of age. The volunteers were treated with triflusal (600 mg/day) for 5 days and platelets and neutrophils were isolated before and after treatment. The ability of neutrophils to produce NO and the capacity of inhibiting platelet aggregation and secretion of transforming growth factor-beta (TGF-beta) were assessed.

RESULTS

After the treatment with triflusal we obtained the following results: a) an increase in NO production by neutrophils; b) potentiation of the inhibition of platelet aggregation by neutrophils, an effect that was reverted by incubating neutrophils with an L-arginine antagonist, L-NAME, and c) the presence of neutrophils reduced the release of TGF-beta by platelets measured as index of platelet secretion by a NO-independent mechanism.

CONCLUSIONS

Triflusal (600 mg/day/5 days) stimulated NO production by neutrophils. After the treatment with triflusal, neutrophils inhibited both platelet aggregation and secretion. The antiaggregating effect of neutrophils was an NO-dependent mechanism while the inhibition of platelet secretion mediated by neutrophils after the treatment with triflusal was an NO-independent mechanism.

Estrogen stimulates neuronal nitric oxide synthase protein expression in human neutrophils

Recent studies have postulated the contribution of nitric oxide (NO) released by the endothelium to the beneficial effects of estrogen. Despite a neuronal-type NO synthase (nNOS) described in neutrophils, less is known about the effect of estrogen in these cells. The aim of the present study was to analyze the expression of nNOS protein in human neutrophils under different estrogenic conditions. We first analyzed nNOS expression in neutrophils obtained from premenopausal women. During the first 2 days of the follicular phase (low circulating estrogen concentrations), nNOS expression in neutrophils was reduced with respect to that found in neutrophils obtained from the same donors during the ovulatory phase (high circulating estrogen concentrations). Moreover, the expression of nNOS protein in neutrophils obtained from postmenopausal women after transdermal estrogen therapy was markedly enhanced with respect to that observed before the treatment. In vitro incubation of neutrophils derived from men for 6 hours with 17beta-estradiol (10(-10) to 10(-8) mol/L) upregulated the expression of nNOS protein. The 17beta-estradiol receptor antagonists, tamoxifen (10(-8) mol/L) and ICI 182780 (10(-8) mol/L), inhibited the upregulation of nNOS protein induced by 17beta-estradiol. The putative functional implication was denoted by a reduced expression of the CD18 antigen on the surface of 17beta-estradiol-incubated neutrophils, which was accompanied by a decreased adhesive capacity. Both effects were prevented by an NO antagonist. In conclusion, the in vivo levels of circulating estrogen concentrations seem to be associated with the level of nNOS protein expression in neutrophils from women. Moreover, low doses of 17beta-estradiol upregulate nNOS protein expression in neutrophils from men. The increased ability of 17beta-estradiol-incubated neutrophils derived from men to produce NO reduced their adhesive properties.

NO from smooth muscle cells decreases NOS expression in endothelial cells: role of TNF-alpha

Despite the evidence that cytokines stimulate nitric oxide (NO) production by inducible nitric oxide synthase (iNOS), several reports recently demonstrated that the hypotensive response related to endothelial nitric oxide synthase (eNOS) activity could be inhibited by the same cytokines. The aim of the present work was to analyze whether NO generated by vascular smooth muscle cells (VSMC) could modify eNOS protein expression in endothelial cells. Bovine aortic endothelial cells (BAEC) and bovine VSMC (BVSMC) in coculture were used for the study. Interleukin-1beta (IL-1beta, 10 ng/ml)-treated BVSMC, which expressed iNOS protein, decreased eNOS protein expression in BAEC. The presence of NO antagonists N(omega)-nitro-L-arginine methyl ester (10(-3) mol/l) or N(G)-monomethyl-L-arginine (10(-3) mol/l) prevented the decrease in eNOS protein expression induced by IL-1beta-treated BVSMC. Surprisingly, two different NO donors, 3-morpholinosydnonimine (10(-4) mol/l) and S-nitroso-N-acetyl-D,L-penicillamine (10(-4) mol/l), failed to modify eNOS expression in BAEC, suggesting the existence of a diffusible mediator released from IL-1beta-treated BVSMC that acts on endothelial cells by reducing eNOS expression. The presence of NO antagonists reduced tumor necrosis factor-alpha (TNF-alpha) production by IL-1beta-stimulated BVSMC. This effect was also produced in the presence of a protein kinase G inhibitor, guanosine-5'-O-(2-thiodiphosphate) trilithium salt. A polyclonal antibody against TNF-alpha prevented eNOS expression in the BAEC-BVSMC coculture. In conclusion, NO by itself failed to modify eNOS protein expression in endothelial cells but increased TNF-alpha generation by IL-1beta-stimulated BVSMC and, in this way, reduced eNOS expression in the endothelium.

[Psammomatoid ossifying fibroma. Apropos a case]

A 41-year-old woman had a left palatal tumor diagnosed as psammomatoid ossifying fibroma. This tumor is a rare subtype of benign fibro-osseous craniofacial lesion that occurs mainly in women, younger age groups, and the sinonasal tract. It has distinctive histomorphological features. The tumor is slow-growing but tends to be locally aggressive and to destroy adjacent anatomic structures. Surgical excision with broad margins is the treatment of choice.

Brugada-like electrocardiographic pattern in a patient with a mediastinal tumor

We report on a patient with a mediastinal tumor and electrocardiographic findings similar to those described in the Brugada syndrome. This peculiar ECG pattern disappeared after tumor removal, thus suggesting it was probably caused by compression of the right ventricular outflow tract by the mass.