Excessive erythrocytosis compromises the blood-endothelium interface in erythropoietin-overexpressing mice

Elevated systemic haematocrit (Hct) increases risk of cardiovascular disorders, such as stroke and myocardial infarction. One possible pathophysiological mechanism could be a disturbance of the blood-endothelium interface. It has been shown that blood interacts with the endothelial surface via a thick hydrated macromolecular layer (the 'glycocalyx', or 'endothelial surface layer'--ESL), modulating various biological processes, including inflammation, permeability and atherosclerosis. However, the consequences of elevated Hct on the functional properties of this interface are incompletely understood. Thus, we combined intravital microscopy of an erythropoietin overexpressing transgenic mouse line (tg6) with excessive erythrocytosis (Hct 0.85), microviscometric analysis of haemodynamics, and a flow simulation model to assess the effects of elevated Hct on glycocalyx/ESL thickness and flow resistance. We show that the glycocalyx/ESL is nearly abolished in tg6 mice (thickness: wild-type control: 0.52 μm; tg6: 0.13 μm; P < 0.001). However, the corresponding reduction in network flow resistance contributes <20% to the maintenance of total peripheral resistance observed in tg6 mice. This suggests that the pathological effects of elevated Hct in these mice, and possibly also in polycythaemic humans, may relate to biological corollaries of a reduced ESL thickness and the consequent alteration in the blood-endothelium interface, rather than to an increase of flow resistance.

Expression of ADAMTS1 in endothelial cells is induced by shear stress and suppressed in sprouting capillaries

ADAMTS1 inhibits capillary sprouting, and since capillary sprouts do not experience the shear stress caused by blood flow, this study undertook to clarify the relationship between shear stress and ADAMTS1. It was found that endothelial cells exposed to shear stress displayed a strong upregulation of ADAMTS1, dependent upon both the magnitude and duration of their exposure. Investigation of the underlying pathways demonstrated involvement of phospholipase C, phosphoinositide 3-kinase, and nitric oxide. Forkhead box protein O1 was identified as a likely inhibitor of the system, as its knockdown was followed by a slight increase in ADAMTS1 expression. In silico prediction displayed a transcriptional binding site for Forkhead box protein O1 in the promotor region of the ADAMTS1 gene, as well as sites for nuclear factor 1, SP1, and AP-1. The anti-angiogenic effects of ADAMTS1 were attributed to its cleavage of thrombospondin 1 into a 70-kDa fragment, and a significant enhancement of this fragment was indeed demonstrated by immunoblotting shear stress-treated cells. Accordingly, scratch wound closure displayed a slowdown in conditioned medium from shear stress-treated endothelial cells, an effect that could be completely blocked by a knockdown of thrombospondin 1 and partially blocked by a knockdown of ADAMTS1. Non-perfused capillary sprouts in rat mesenteries stained negative for ADAMTS1, while vessels in the microcirculation that had already experienced blood flow yielded the opposite results. The shear stress-dependent expression of ADAMTS1 in vitro was therefore also demonstrated in vivo and thereby confirmed as a mechanism connecting blood flow with the regulation of angiogenesis.

Autologous stem cell transplantation: leukapheresis product has anti-angiogenic effects in vivo correlating with neutrophil-derived VEGFR1

High-dose chemotherapy (HDC) followed by autologous stem cell transplantation (ASCT) is used for the treatment of hemato-oncologic malignancies. In this study, we measured the effect of HDC/ASCT on plasma concentrations of antiangiogenic soluble vascular endothelial growth factor receptor 1 (sVEGFR1) and of leukapheresis products (LP) and patient serum on chick chorioallantoic (CAM) angiogenesis.

Validation of prognostic factors and survival of patients with multiple myeloma in a real-life autologous stem cell transplantation setting: a Swiss single centre experience

High-dose chemotherapy with subsequent autologous stem cell transplantation (ASCT) is an important treatment option in younger patients with multiple myeloma (MM). We analysed the outcome of patients treated at our institution outside the clinical trials framework and tried to identify risk factors prognostic for survival.

Long-term clinical outcomes of biodegradable polymer biolimus-eluting stents versus durable polymer sirolimus-eluting stents in patients with coronary artery disease (LEADERS): 4 year follow-up of a randomised non-inferiority trial

Background The effectiveness of durable polymer drug-eluting stents comes at the expense of delayed arterial healing and subsequent late adverse events such as stent thrombosis (ST). We report the 4 year follow-up of an assessment of biodegradable polymer-based drug-eluting stents, which aim to improve safety by avoiding the persistent inflammatory stimulus of durable polymers. Methods We did a multicentre, assessor-masked, non-inferiority trial. Between Nov 27, 2006, and May 18, 2007, patients aged 18 years or older with coronary artery disease were randomly allocated with a computer-generated sequence to receive either biodegradable polymer biolimus-eluting stents (BES) or durable polymer sirolimus-eluting stents (SES; 1:1 ratio). The primary endpoint was a composite of cardiac death, myocardial infarction, or clinically-indicated target vessel revascularisation (TVR); patients were followed-up for 4 years. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00389220. Findings 1707 patients with 2472 lesions were randomly allocated to receive either biodegradable polymer BES (857 patients, 1257 lesions) or durable polymer SES (850 patients, 1215 lesions). At 4 years, biodegradable polymer BES were non-inferior to durable polymer SES for the primary endpoint: 160 (18·7%) patients versus 192 (22·6%) patients (rate ratios [RR] 0·81, 95% CI 0·66–1·00, p for non-inferiority <0·0001, p for superiority=0·050). The RR of definite ST was 0·62 (0·35–1·08, p=0·09), which was largely attributable to a lower risk of very late definite ST between years 1 and 4 in the BES group than in the SES group (RR 0·20, 95% CI 0·06–0·67, p=0·004). Conversely, the RR of definite ST during the first year was 0·99 (0·51–1·95; p=0·98) and the test for interaction between RR of definite ST and time was positive (pinteraction=0·017). We recorded an interaction with time for events associated with ST but not for other events. For primary endpoint events associated with ST, the RR was 0·86 (0·41–1·80) during the first year and 0·17 (0·04–0·78) during subsequent years (pinteraction=0·049). Interpretation Biodegradable polymer BES are non-inferior to durable polymer SES and, by reducing the risk of cardiac events associated with very late ST, might improve long-term clinical outcomes for up to 4 years compared with durable polymer SES. Funding Biosensors Europe SA, Switzerland.

The three year follow-up of the randomised "all-comers" trial of a biodegradable polymer biolimus-eluting stent versus permanent polymer sirolimus-eluting stent (LEADERS)

Aims: The current study reports clinical outcomes at three year follow-up of the LEADERS clinical trial which was the first all-comers trial comparing a new generation biodegradable polymer biolimus drug-eluting stent (BES) with the first generation permanent polymer sirolimus-eluting stent (SES). Methods and results: One thousand seven hundred and seven patients were randomised to unrestricted use of BES (n=857) or SES (n=850) in an all-comers population. Three year follow-up was available in 95% of the patients, 812 treated with BES and 809 treated with SES. At three years, BES remains non-inferior to SES for the primary endpoint of major adverse cardiac events (composite of cardiac death, myocardial infarction (MI), or clinically-indicated target vessel revascularisation (CI-TVR) (BES 15.7% versus SES 19%; HR 0.82 CI 0.65-1.03; p=0.09). The MACE Kaplan Meier event curves increasingly diverge with the difference in events increasing from 1.4% to 2.4% and 3.3% at 1, 2 and 3 years, respectively in favour of BES. The rate of cardiac death was non-significantly lower 4.2% versus 5.2% (HR=0.81 CI 0.52-1.26; p=0.34) and the rate of myocardial infarction was equivalent 7.2% versus 7.1% (HR 1.01 CI 0.70-1.44; p=0.97) for BES versus SES, respectively. Thus BES was non-inferior to SES in all the safety endpoints. Clinically-indicated TVR occurred in 9.4% of BES treated patients versus 11.1% of SES treated patients (HR 0.84 CI 0.62-1.13; p=0.25). Rates of definite stent thrombosis were 2.2% for BES and 2.9% for SES (HR 0.78 CI 0.43-1.43; p=0.43), with the event rate increase of 0.2% from one to three years for BES and 0.9% for SES. For patients presenting with ST-elevation myocardial infarction BES was superior to SES in reducing MACE. Conclusions: The findings of the three year follow-up support the claim that the biodegradable polymer biolimus-eluting stent has equivalent safety and efficacy to permanent polymer sirolimus-eluting stent in an all-comers patient population. Its performance is superior in some subpopulations such as in ST-elevation MI patients and event rates for BES are overall lower than for SES with a trend toward increasing divergence of outcomes over three years. - See more at: http://www.pcronline.com/eurointervention/42nd_issue/125/#sthash.E5HhMQ4a.dpuf

Implantation of the biodegradable polymer biolimus-eluting stent in patients with high SYNTAX score is associated with decreased cardiac mortality compared to a permanent polymer sirolimus-eluting stent: two year follow-up results from the "all-comers" LEADERS trial

Background: The SYNTAX score (SXscore) has been shown to be an effective predictor of clinical outcomes in patients undergoing percutaneous coronary intervention (PCI). Methods and results: The SXscore was prospectively collected in 1,397 of the 1,707 patients enrolled in the “all-comers” LEADERS trial (patients post-surgical revascularisation were excluded). Post hoc analysis was performed by stratifying clinical outcomes at two-year follow-up, according to one of three SXscore tertiles: SXlow ≤8 (n=464), 816 (n=461). At two-year follow-up the rate of major adverse cardiovascular events was 18.4%, 12.0% and 9.4% in the SXhigh, SXmid, and SXlow tertile, respectively (HR 1.45; CI 1.21-1.74; p<0.01). There was a significantly higher rate of cardiac death in patients in the highest SXscore tertile (7% SXhigh versus 2.4% SXmid versus 1.8% SXlow; HR 2.22; CI 1.5-3.27; p<0.001). Within the SXhigh tertile the rate of cardiac death was significantly lower in patients treated with the biolimus-eluting stent compared with the sirolimus-eluting stent (4.7% versus 9.6%, HR 0.48; CI 0.23-0.99; p=0.046). Conclusions: The SXscore when applied to an “all-comers” patient population allows for prospective risk stratification of patients undergoing PCI up to two years follow-up. In addition, the SXscore appears to separate the performance of devices in high risk patient groups.

Two-year clinical follow-up from the randomized comparison of biolimus-eluting stents with biodegradable polymer and sirolimus-eluting stents with durable polymer in routine clinical practice

Objectives This study sought to investigate safety and efficacy of biolimus-eluting stents (BES) with biodegradable polymer as compared with sirolimus-eluting stents (SES) with durable polymer through 2 years of follow-up. Background BES with a biodegradable polymer provide similar efficacy and safety as SES with a durable polymer at 9 months. Clinical outcomes beyond the period of biodegradation of the polymer used for drug release and after discontinuation of dual antiplatelet therapy are of particular interest. Methods A total of 1,707 patients were randomized to unrestricted use of BES (n = 857) or SES (n = 850) in an all-comers patient population. Results At 2 years, BES remained noninferior compared with SES for the primary endpoint, which was a composite of cardiac death, myocardial infarction, or clinically indicated target vessel revascularization (BES 12.8% vs. SES 15.2%, hazard ratio [HR]: 0.84, 95% confidence interval [CI]: 0.65 to 1.08, pnoninferiority < 0.0001, psuperiority = 0.18). Rates of cardiac death (3.2% vs. 3.9%, HR: 0.81, 95% CI: 0.49 to 1.35, p = 0.42), myocardial infarction (6.3% vs. 5.6%, HR: 1.12, 95% CI: 0.76 to 1.65, p = 0.56), and clinically indicated target vessel revascularization (7.5% vs. 8.6%, HR: 0.86, 95% CI: 0.62 to 1.20, p = 0.38) were similar for BES and SES. The rate of definite stent thrombosis through 2 years was 2.2% for BES and 2.5% for SES (p = 0.73). For the period between 1 and 2 years, event rates for definite stent thrombosis were 0.2% for BES and 0.5% for SES (p = 0.42). After discontinuation of dual antiplatelet therapy, no very late definite stent thrombosis occurred in the BES group. Conclusions At 2 years of follow-up, the unrestricted use of BES with a biodegradable polymer maintained a similar safety and efficacy profile as SES with a durable polymer. (Limus Eluted From a Durable Versus Erodable Stent Coating [LEADERS]; NCT00389220)

The impact of patient and lesion complexity on clinical and angiographic outcomes after revascularization with zotarolimus- and everolimus-eluting stents: a substudy of the RESOLUTE All Comers Trial (a randomized comparison of a zotarolimus-eluting stent with an everolimus-eluting stent for percutaneous coronary intervention)

The aim of this study was to investigate the impact of patient and lesion complexity on outcomes with newer-generation zotarolimus-eluting stents (ZES) and everolimus-eluting stents (EES).

The prognostic utility of the SYNTAX score on 1-year outcomes after revascularization with zotarolimus- and everolimus-eluting stents: a substudy of the RESOLUTE All Comers Trial

This study assessed the ability of the SYNTAX score (SXscore) to stratify risk in patients treated with percutaneous coronary intervention (PCI) using zotarolimus-eluting or everolimus-eluting stents.

Value of age, creatinine, and ejection fraction (ACEF score) in assessing risk in patients undergoing percutaneous coronary interventions in the 'All-Comers' LEADERS trial

Background— The age, creatinine, and ejection fraction (ACEF) score (age/left ventricular ejection fraction+1 if creatinine >2.0 mg/dL) has been established as an effective predictor of clinical outcomes in patients undergoing elective coronary artery bypass surgery; however, its utility in “all-comer” patients undergoing percutaneous coronary intervention is yet unexplored. Methods and Results— The ACEF score was calculated for 1208 of the 1707 patients enrolled in the LEADERS trial. Post hoc analysis was performed by stratifying clinical outcomes at the 1-year follow-up according to ACEF score tertiles: ACEFlow ≤1.0225, 1.0225< ACEFmid ≤1.277, and ACEFhigh >1.277. At 1-year follow-up, there was a significantly lower number of patients with major adverse cardiac event–free survival in the highest tertile of the ACEF score (ACEFlow=92.1%, ACEFmid=89.5%, and ACEFhigh=86.1%; P=0.0218). Cardiac death was less frequent in ACEFlow than in ACEFmid and ACEFhigh (0.7% vs 2.2% vs 4.5%; hazard ratio=2.22, P=0.002) patients. Rates of myocardial infarction were significantly higher in patients with a high ACEF score (6.7% for ACEFhigh vs 5.2% for ACEFmid and 2.5% for ACEFlow; hazard ratio=1.6, P=0.006). Clinically driven target-vessel revascularization also tended to be higher in the ACEFhigh group, but the difference among the 3 groups did not reach statistical significance. The rate of composite definite, possible, and probable stent thrombosis was also higher in the ACEFhigh group (ACEFlow=1.2%, ACEFmid=3.5%, and ACEFhigh=6.2%; hazard ratio=2.04, P<0.001). Conclusions— ACEF score may be a simple way to stratify risk of events in patients treated with percutaneous coronary intervention with respect to mortality and risk of myocardial infarction.

Celecoxib enhances radiation response of secondary bone tumors of a human non-small cell lung cancer via antiangiogenesis in vivo

Cyclooxygenase-2 (COX-2) inhibitors mediate a systemic antitumor activity via antiangiogenesis and seem to enhance the response of primary tumors to radiation. Radiosensitizing effects of COX-2 inhibition have not been reported for bone metastases. Therefore, the aim of this study was the investigation of the radiosensitizing effects of the selective COX-2 inhibitor celecoxib in secondary bone tumors of a non-small cell lung carcinoma in vivo.

Interleukin-6, -7, -8 and -10 predict outcome in acute myocardial infarction complicated by cardiogenic shock

The IABP-SHOCK-trial was a morbidity-based randomized controlled trial in patients with infarction-related cardiogenic shock (CS), which used the change of the quantified degree of multiorgan failure as determined by APACHE II score over a 4-day period as primary outcome measure. The prospective hypothesis was that adding IABP therapy to "standard care" would improve CS-triggered multi organ dysfunction syndrome (MODS). The primary endpoint showed no difference between conventionally managed cardiogenic shock patients and those with IABP support. In an inflammatory marker substudy, we analysed the prognostic value of interleukin (IL)-1β, -6, -7, -8, and -10 in patients with acute myocardial infarction complicated by cardiogenic shock.

Constrained pattern of viral evolution in acute and early HCV infection limits viral plasticity

Cellular immune responses during acute Hepatitis C virus (HCV) and HIV infection are a known correlate of infection outcome. Viral adaptation to these responses via mutation(s) within CD8+ T-cell epitopes allows these viruses to subvert host immune control. This study examined HCV evolution in 21 HCV genotype 1-infected subjects to characterise the level of viral adaptation during acute and early HCV infection. Of the total mutations observed 25% were within described CD8+ T-cell epitopes or at viral adaptation sites. Most mutations were maintained into the chronic phase of HCV infection (75%). The lack of reversion of adaptations and high proportion of silent substitutions suggests that HCV has structural and functional limitations that constrain evolution. These results were compared to the pattern of viral evolution observed in 98 subjects during a similar phase in HIV infection from a previous study. In contrast to HCV, evolution during acute HIV infection is marked by high levels of amino acid change relative to silent substitutions, including a higher proportion of adaptations, likely reflecting strong and continued CD8+ T-cell pressure combined with greater plasticity of the virus. Understanding viral escape dynamics for these two viruses is important for effective T cell vaccine design.