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The Palaeogene layered ultrabasic intrusion of the Isle of Rum forms the hearth of the Rum Igneous Centre in NW-Scotland. The regional Long Loch Fault, which is widely held to represent the feeder system to the layered magma reservoir, dissects the intrusion and is marked by extensive ultrabasic breccias of various types. Here we explore the connection between the layered ultrabasic cumulate rocks and breccias of central Rum that characterize the fault zone (the 'Central Series') and evaluate their relationship with the Long Loch Fault system. We show that fault splays in the Central Series define a transtensional graben above the Long Loch Fault into which portions of the layered units subsided and collapsed to form the extensive breccias of central Rum. The destabilization of the cumulate pile was aided by intrusion of Ca-rich ultrabasic magmas along the faults, fractures and existing bedding planes, creating a widespread network of veins and dykelets that provided a further means of disintegration and block detachment. Enrichment in LREE and compositional zoning in intra cumulate interstices suggest that the collapsed cumulates were infiltrated by relatively evolved plagioclase-rich melt, which led to extensive re-crystallization of interstices. Clinopyroxene compositions in Ca-rich gabbro and feldspathic peridotite veins suggest that the intruding magma was also relatively water-rich, and that pyroxene crystallized dominantly below the current level of exposure. We propose that the Long Loch Fault opened and closed repeatedly to furnish the Rum volcano with a pulsing magma conduit. When the conduit was shut, pressure built up in the underlying plumbing system, but was released during renewed fault movements to permit dense and often crystal-rich ultrabasic magmas to ascend rapidly from depth. These spread laterally on arrival in the shallow Rum magma reservoir, supplying repetitive recharges of crystal-rich magma to assemble the rhythmic layering of the Rum layered intrusion. [ABSTRACT FROM AUTHOR]

Background: Infection is a main cause of morbidity and mortality after heart surgery, with multi-resistant pathogens increasingly representing a challenge. Daptomycin provides bactericidal activity against gram-positive organisms that are resistant to standard treatment including vancomycin.Methods: A cohort of cardiac surgical patients, treated with daptomycin for major infection at two tertiary care centers, were retrospectively studied with a particular focus on the type of infection, causative pathogens and co-infections, daptomycin dosage, adverse events and outcome in order to provide evidence for the efficiency and safety of daptomycin in a distinct high-risk patient population.Results: Sixty-five patients (87.7 % males, 60.4 ± 13.5 years) who had undergone aortic surgery (20.0 %), ventricular assist device (VAD) implantation (21.5 %), combined procedures (21.5 %), coronary artery bypass grafting (12.3 %), isolated valve surgery (15.4 %) and heart transplantation (7.7 %) were diagnosed with catheter-related infection (26.1 %), valve endocarditis (18.8 %), sternal wound (13.0 %), VAD-associated (11.6 %), cardiac implantable electrophysiological device (CIED)-associated (4.1 %), respiratory tract (4.3 %), bloodstream (4.3 %) and other infection (4.3 %). In 13.0 %, no focus of infection was identified though symptoms of severe infection were present. The most frequent pathogens were Staphylococcus epidermidis (30.4 %), Staphylococcus aureus (23.1 %) and Enterococcus species (10.1 %). Daptomycin doses ranging from 3 mg/kg every 48 h to 10 mg/kg every 24 h were administered for 15.4 ± 11.8 days. 87.0 % of the cases were classified as success, 7.2 % as treatment failure and 5.8 as non-evaluable. Adverse events were limited to one case of mild and one case of moderate neutropenia with recovery upon termination of treatment.Conclusion: Daptomycin proved safe and effective in major infection in high-risk cardiac surgical patients. [ABSTRACT FROM AUTHOR]

BACKGROUND: Epinephrine enhances emotional memory whereas beta-adrenoceptor antagonists (beta-blockers, BBs) impair it. However, the effects of BB administration on memory are sex dependent. Therefore, we predicted differential effects of epinephrine and the BB metoprolol given to male and female patients after cardiac surgery (CS) on traumatic memories and post-traumatic stress disorder (PTSD) symptoms. METHOD: We performed a prospective observational study and determined the number of standardized traumatic memories (NTRM) and PTSD symptom intensity in cardiac surgical patients at 1 day before surgery, and at 1 week and 6 months after the procedure. PTSD symptoms and NTRM were quantified using validated questionnaires. Metoprolol could be administered any time post-operatively. RESULTS: Baseline NTRM was not significantly different between male (n=95) and female patients (n=33). One week after CS, the NTRM in male patients was significantly higher. Metoprolol had no significant effect in either sex. At 6 months, females with metoprolol (n=18) showed a significantly lower NTRM and significantly lower PTSD symptom scores than females without BBs (n=15, p=0.02). By contrast, the totally administered dosage of epinephrine correlated with NTRM in males (r=0.33, p<0.01) but not in females (r=0.21, p=0.29). CONCLUSIONS: beta-Adrenergic stimulation with epinephrine enhances memory for adverse experiences in males but not in females whereas beta-blockade selectively reduces memory for post-operative adverse events and PTSD symptoms in females. [ABSTRACT FROM AUTHOR]

The Infostations system, small and separated islands of coverage, provides intermittent but very high speed data rates. A new communication model is needed to carry this kind of architecture. Mainly, the discontinuous coverage affects the way data are exchanged between mobile terminals and the network. Moreover, the short time the mobile terminal spends in the coverage area has a direct impact on the network performance. Thus, it is essential to avoid bandwidth wasting due to the overall delay by performing mobility prediction. A new mobility prediction protocol called the Distributed Neighbor Discovery Protocol (DNDP) is proposed. DNDP handles a neighbor graph table that dynamically configures itself according to the terminals' mobility. The simulation shows that the terminals service continuity is significantly improved thanks to DNDP. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We report a 56-year-old male patient developing hypoxemia after surgical replacement of infected valves of a left ventricular assist device (LVAD, Novacor) which had supported him during the previous 15 months. Contrast transesophageal echocardiography (TEE) revealed an atrial septal defect with intermittent right-to-left shunt across a patent foramen ovale. We postulate that the shunt detected in this patient occurred as a consequence of reduced pulmonary vascular compliance due to positive end-expiratory pressure (PEEP) and an increase of mean intrathoracic pressure. Furthermore, we hypothesize that synchronized LVAD operation exacerbates any potential right-to-left shunt due to the profound left ventricular unloading which occurs during LVAD support. In this first report of a right-to-left shunt from a previously unrecognized patent foramen ovale in a Novacor patient, the subsequent transient hypoxemia could be managed by avoiding PEEP of more than 3 mmHg, and mean airway pressure of more than 11 mmHg and by careful volume replacement in order to prevent the pump from completely emptying the left ventricle (LV) and the left atrium (LA). Thus, prior to every LVAD implantation a transesophageal contrast echocardiography with Valsalva maneuver should be performed to identify intracardiac right-to-left shunt. [ABSTRACT FROM AUTHOR]

Abstract Background Mediastinitis is a severe complication after cardiac surgery. While improvement of prophylaxis and of medical and surgical therapy has reduced its incidence, the treatment of mediastinitis continues to be a challenging problem. Within this study, we report the successful use of daptomycin as supportive therapy in patients developing mediastinitis after open cardiac surgery. Methods The records of 21 consecutive patients who developed mediastinitis after cardiac surgery were retrospectively reviewed. After diagnosis, all patients received surgical debridement and antibiotic therapy with daptomycin. All patients were followed up to death or discharge. Results Clinical improvement after combined surgical and antibiotic therapy with daptomycin was found in 90.5% of the patients. The median time until clinical improvement occurred was 5 [4/6] days. Daptomycin was well-tolerated and no major adverse events during therapy were observed observed. Conclusions This study provides new and helpful information regarding the beneficial use of daptomycin as supportive treatment option in patients developing mediastinitis after cardiac surgery.

Replies to a commentary on a case report concerning temporary hypoxemia from right-to-left shunting in a patient during support with a left ventricular assist device and a patent foramen ovale previously published in the periodical 'Acta Anaesthesiological Scandinavia' in 2000. Shunting triggered by the device; Causes of the closure of the patent foramen ovale.