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Abstract Background Thrombolysis with intravenous rt-PA is currently the only approved acute therapy for ischemic stroke. Re-occlusion after initial recanalization occurs in up to 34% in patients treated with rt-PA, probably caused by platelet activation. In acute myocardial infarction, the combination of thrombolysis and antiplatelet therapy leads to a greater reduction of mortality compared to thrombolysis alone. In patients with acute ischemic stroke, several studies showed that patients already on antiplatelet treatment prior to thrombolysis had an equal or even better outcome compared to patients without prior antiplatelet treatment, despite an increased risk of intracerebral bleeding. Based on the fear of intracerebral haemorrhage, current international guidelines recommend postponing antiplatelet therapy until 24 hours after thrombolysis. Remarkably, prior use of antiplatelet therapy is not a contra-indication for thrombolysis. We hypothesize that antiplatelet therapy in combination with rt-PA thrombolysis will improve outcome by enhancing fibrinolysis and preventing re-occlusion. Methods/Design ARTIS is a randomised multi-center controlled trial with blind endpoint assessment. Our objective is to investigate whether immediate addition of aspirin to rt-PA thrombolysis improves functional outcome in ischemic stroke. Patients with acute ischemic stroke eligible for rt-PA thrombolysis are randomised to receive 300 mg aspirin within 1.5 hours after start of thrombolysis or standard care, consisting of antiplatelet therapy after 24 hours. Primary outcome is poor functional health at 3 months follow-up (modified Rankin Scale 3 - 6). Discussion This is the first clinical trial investigating the combination of rt-PA and acute aspirin by means of a simple and cheap adjustment of current antiplatelet regimen. We expect the net benefit of improved functional outcome will overcome the possible slightly increased risk of intracerebral haemorrhage. Trial registration The Netherlands National Trial Register NTR822. The condensed rationale of the ARTIS-Trial has already been published in Cerebrovascular Diseases.

Plants are part of biodiverse communities and frequently suffer from attack by multiple herbivorous insects. Plant responses to these herbivores are specific for insect feeding guilds: aphids and caterpillars induce different plant phenotypes. Moreover, plants respond differentially to single or dual herbivory, which may cascade into a chain of interactions in terms of resistance to other community members. Whether differential responses to single or dual herbivory have consequences for plant resistance to yet a third herbivore is unknown., We assessed the effects of single or dual herbivory by Brevicoryne brassicae aphids and/or Plutella xylostella caterpillars on resistance of plants from three natural populations of wild cabbage to feeding by caterpillars of Mamestra brassicae. We measured plant gene expression and phytohormone concentrations to illustrate mechanisms involved in induced responses., Performance of both B. brassicae and P. xylostella was reduced when feeding simultaneously with the other herbivore, compared to feeding alone. Gene expression and phytohormone concentrations in plants exposed to dual herbivory were different from those found in plants exposed to herbivory by either insect alone. Plants previously induced by both P. xylostella and B. brassicae negatively affected growth of the subsequently arriving M. brassicae. Furthermore, induced responses varied between wild cabbage populations., Feeding by multiple herbivores differentially activates plant defences, which has plant-mediated negative consequences for a subsequently arriving herbivore. Plant population-specific responses suggest that plant populations adapt to the specific communities of insect herbivores. Our study contributes to the understanding of plant defence plasticity in response to multiple insect attacks. [ABSTRACT FROM AUTHOR]

Patients with recent cerebral venous sinus thrombosis (CVT) should be fully anticoagulated with heparin as soon as the diagnosis is confirmed, even in the presence of cerebral hemorrhagic venous infarcts. Fixed-dose subcutaneous low-molecular-weight heparins (LMWH) in therapeutic dosage have a better safety profile and are probably more effective than dose-adjusted intravenous unfractionated heparin. After the patient is stabilized , oral anticoagulant treatment is started, aimed at an INR value between 2.0 and 3.0 for at least three months after the acute phase. Since about 40 % of patients with CVT have epileptic seizures at onset or during the first days, many require treatment with anti-epileptics. Prophylactic anti-epileptic treatment is an option, but its efficacy has not been investigated. If no new seizures occur after the acute phase, anti-epileptics can be tapered after three to six months. The efficacy of endovascular treatment, with mechanical and/or pharmacologic thrombolysis, has only been published in small case series, and cannot be regarded as proven effective treatment for CVT. Its theoretical advantage of more rapid clearance of thrombi may be offset by severe bleeding complications, and the limited availability and higher cost of the procedure. Patients who deteriorate because of large space-occupying venous infarcts have a high risk of dying from cerebral herniation. In such cases an emergent decompressive hemicraniectomy is often life-saving. Experience from different centers with this procedure shows a good clinical outcome in the majority of these patients. Patients with CVT may develop - and sometimes present with - chronic intracranial hypertension with headache and papilledema. In such patients the priority is prevention of visual function loss; intracranial hypertension should be controlled with acetazolamide, and occasionally with repeated lumbar punctures if vision is threatened. Refractory cases will need a CSF shunting procedure. [ABSTRACT FROM AUTHOR]

Natural hazards threaten the urban system and its components that are likely to fail. With their high degree of interdependency, urban networks and services are critical issues for the resilience of a city. And yet, network managers are scarcely aware of their flaws and dependencies and they are reluctant to take them into account. In order to develop an operational tool to improve urban resilience, we propose here an auto-diagnosis method to be completed by network managers. The subsequent confrontation of all diagnoses is the basis of collaborative research for problem identification and solution design. The tool is experimented with the Parisian urban transport society. [ABSTRACT FROM AUTHOR]

Background: Thrombolysis with intravenous rt-PA is currently the only approved acute therapy for ischemic stroke. Re-occlusion after initial recanalization occurs in up to 34% in patients treated with rt-PA, probably caused by platelet activation. In acute myocardial infarction, the combination of thrombolysis and antiplatelet therapy leads to a greater reduction of mortality compared to thrombolysis alone. In patients with acute ischemic stroke, several studies showed that patients already on antiplatelet treatment prior to thrombolysis had an equal or even better outcome compared to patients without prior antiplatelet treatment, despite an increased risk of intracerebral bleeding. Based on the fear of intracerebral haemorrhage, current international guidelines recommend postponing antiplatelet therapy until 24 hours after thrombolysis. Remarkably, prior use of antiplatelet therapy is not a contra-indication for thrombolysis. We hypothesize that antiplatelet therapy in combination with rt-PA thrombolysis will improve outcome by enhancing fibrinolysis and preventing re-occlusion. Methods/Design: ARTIS is a randomised multi-center controlled trial with blind endpoint assessment. Our objective is to investigate whether immediate addition of aspirin to rt-PA thrombolysis improves functional outcome in ischemic stroke. Patients with acute ischemic stroke eligible for rt-PA thrombolysis are randomised to receive 300 mg aspirin within 1.5 hours after start of thrombolysis or standard care, consisting of antiplatelet therapy after 24 hours. Primary outcome is poor functional health at 3 months follow-up (modified Rankin Scale 3 - 6). Discussion: This is the first clinical trial investigating the combination of rt-PA and acute aspirin by means of a simple and cheap adjustment of current antiplatelet regimen. We expect the net benefit of improved functional outcome will overcome the possible slightly increased risk of intracerebral haemorrhage. Trial registration: The Netherlands National Trial Register NTR822. The condensed rationale of the ARTIS-Trial has already been published in Cerebrovascular Diseases. [ABSTRACT FROM AUTHOR]