158 research outputs found
SafeWeb: A Middleware for Securing Ruby-Based Web Applications
Web applications in many domains such as healthcare and finance must process sensitive data, while complying with legal policies regarding the release of different classes of data to different parties. Currently, software bugs may lead to irreversible disclosure of confidential data in multi-tier web applications. An open challenge is how developers can guarantee these web applications only ever release sensitive data to authorised users without costly, recurring security audits.
Our solution is to provide a trusted middleware that acts as a âsafety netâ to event-based enterprise web applications by preventing harmful data disclosure before it happens. We describe the design and implementation of SafeWeb, a Ruby-based middleware that associates data with security labels and transparently tracks their propagation at different granularities across a multi-tier web architecture with storage and complex event processing. For efficiency, maintainability and ease-of-use, SafeWeb exploits the dynamic features of the Ruby programming language to achieve label propagation and data flow enforcement. We evaluate SafeWeb by reporting our experience of implementing a web-based cancer treatment application and deploying it as part of the UK National Health Service (NHS)
Transcatheter aortic valve implantation for severe aortic stenosis. 30-day outcomes of singlecenter experience
Wprowadzenie. PrzezskĂłrne wszczepienie zastawki aortalnej (TAVI) jest alternatywÄ
dla chirurgicznej wymiany zastawki aortalnej.
Cel. Ocena ryzyka okoĹoproceduralnego TAVI, skutecznoĹci implantacji oraz wynikĂłw leczenia bezpoĹredniego i 30-dniowej obserwacji pacjentĂłw z Kliniki Kardiologii Inwazyjnej Centralnego Szpitala Klinicznego MSWiA.
MateriaĹy i metody. AnalizÄ
objÄto 45 chorych zakwalifikowanych do przezskĂłrnego wszczepienia zastawki aortalnej. Ĺredni wiek leczonej populacji wynosiĹ 82 lata. Kobiety stanowiĹy 55% chorych poddanych zabiegowi. Ĺredni wynik EuroScore II wyniĂłsĹ 4,78%. W badanej populacji dokonano analizy parametrĂłw klinicznych (klasyfikacja NYHA, CCS), biochemicznych (miÄdzy innymi kreatynina, hemoglobina, NT-proBNP) oraz echokardiograficznych (LVEF, AVA). Badani chorzy przed zabiegiem TAVI mieli wykonanÄ
rĂłwnieĹź 64-rzÄdowÄ
tomografiÄ komputerowÄ
(ocena pierĹcienia zastawki oraz dostÄpu naczyniowego) oraz angiografiÄ tÄtnic wieĹcowych. Zastawki CoreValve uĹźyto u 39 pacjentĂłw, Edwards-Sapien u 4, Symetis u 2.
Wyniki. CaĹkowita ĹmiertelnoĹÄ do 30 dni od zabiegu wyniosĹa 4,5 % (n = 2). Nie odnotowano Ĺźadnego zgonu w okresie okoĹozabiegowym. ImplantacjÄ stymulatora po zabiegu TAVI wykonano u szeĹciu chorych ze wzglÄdu na wystÄpowanie bloku lewej odnogi pÄczka Hisa (n = 3) lub wysokiego stopnia bloku przedsionkowo-komorowego (n = 3). CzÄstoĹÄ udaru mĂłzgu wynosiĹa 4,5% (n = 2). U 4,5% (n = 2) pacjentĂłw wystÄ
piĹa tamponada serca niezakoĹczona zgonem. Odnotowano istotne zwiÄkszenie pola powierzchni ujĹcia aortalnego, jak rĂłwnieĹź redukcjÄ gradientu przezzastawkowego i stopnia niedomykalnoĹci zastawki aortalnej, zarĂłwno centralnej, jak i okoĹozastawkowej.
Wnioski. Pacjenci z ciÄĹźkim objawowym zwÄĹźeniem aorty, ktĂłrzy nie zostali zakwalifikowani do chirurgicznej wymiany zastawki aortalnej ze wzglÄdu na zaawansowany wiek, dysfunkcjÄ lewej komory lub wspĂłĹwystÄpowanie wielu czynnikĂłw ryzyka, odnoszÄ
korzyĹci z TAVI. RĂłwnieĹź dla pacjentĂłw bez najwyĹźszego ryzyka chirurgicznego, TAVI moĹźe byÄ korzystnÄ
alternatywÄ
.Â
Introduction. Transcatheter aortic valve implantation (TAVI) is an alternative therapeutic method for surgery aortic valve replacement (AVR).
Aim. To assess periprocedural risk of TAVI and in-hospital and 30-day follow-up result in patients treated in the Department of Invasive Cardiology in Central Clinical Hospital of the Ministry of Interior in Warsaw, Poland. Material and methods. Forty-five aortic stenosis patients (mean age 82 years, 55% females ) not suitable for surgery underwent TAVI. Average EuroScore II was 4.78%. We examined clinical parameters (NYHA and CCS class), biochemical markers (including creatinine, haemoglobin, NT-proBNP) as well echocardiographic (LVEF, AVA) and CT-derived findings. CoreValve was implanted in 39 patients, Edwards Sapien in 4, Symetis in 2.
Results. After 30 days the all-cause mortality rate was 4.5% (n = 2). At 30 days, 6 patients needed permanent stimulation, symptomatic stroke was found in 4.5% (n = 2) of the patients, and cardiac tamponade in 4.5% (n = 2). The aortic valve area and mean pressure gradient were significantly improved. We observed reduction of aortic regurgitation.
Conclusion. The patients with severe symptomatic aortic stenosis do not undergo surgery for replacement of the aortic valve, owing to advanced age, left ventricular dysfunction, or the presence of multiple coexisting conditions were taking benefits from TAVI back. For patients, who are at not a highest surgical risk, TAVI may be a worthwhile alternative
Automatic rule extraction from access rules using Genetic Programming
International audienceThe security policy rules in companies are generally proposed by the Chief Security Officer (CSO), who must, for instance, select by hand which access events are allowed and which ones should be forbidden. In this work we propose a way to automatically obtain rules that gen-eralise these single-event based rules using Genetic Programming (GP), which, besides, should be able to present them in an understandable way. Our GP-based system obtains good dataset coverage and small ratios of false positives and negatives in the simulation results over real data, after testing different fitness functions and configurations in the way of coding the individuals
The interaction of vasoactive substances during exercise modulates platelet aggregation in hypertension and coronary artery disease
<p>Abstract</p> <p>Background</p> <p>Acute vigorous exercise, associated with increased release of plasma catecholamines, transiently increases the risk of primary cardiac arrest. We tested the effect of acute submaximal exercise on vasoactive substances and their combined result on platelet function.</p> <p>Methods</p> <p>Healthy volunteers, hypertensive patients and patients with coronary artery disease (CAD) performed a modified treadmill exercise test. We determined plasma catecholamines, thromboxane A<sub>2</sub>, prostacyclin, endothelin-1 and platelet aggregation induced by adenosine diphosphate (ADP) and collagen at rest and during exercise.</p> <p>Results</p> <p>Our results during exercise showed a) platelet activation (increased thromboxane B<sub>2</sub>, TXB<sub>2</sub>), b) increased prostacyclin release from endothelium and c) decreased platelet aggregation in all groups, significantly more in healthy volunteers than in patients with CAD (with hypertensives lying in between these two groups).</p> <p>Conclusion</p> <p>Despite the pronounced activation of Sympathetic Nervous System (SNS) and increased TXB<sub>2 </sub>levels during acute exercise platelet aggregation decreases, possibly to counterbalance the prothrombotic state. Since this effect seems to be mediated by the normal endothelium (through prostacyclin and nitric oxide), in conditions characterized by endothelial dysfunction (hypertension, CAD) reduced platelet aggregation is attenuated, thus posing such patients in increased risk for thrombotic complications.</p
Effect of Adjunct Metformin Treatment in Patients with Type-1 Diabetes and Persistent Inadequate Glycaemic Control. A Randomized Study
Despite intensive insulin treatment, many patients with type-1 diabetes (T1DM) have longstanding inadequate glycaemic control. Metformin is an oral hypoglycaemic agent that improves insulin action in patients with type-2 diabetes. We investigated the effect of a one-year treatment with metformin versus placebo in patients with T1DM and persistent poor glycaemic control.One hundred patients with T1DM, preserved hypoglycaemic awareness and HaemoglobinA(1c) (HbA(1c)) > or = 8.5% during the year before enrolment entered a one-month run-in on placebo treatment. Thereafter, patients were randomized (baseline) to treatment with either metformin (1 g twice daily) or placebo for 12 months (double-masked). Patients continued ongoing insulin therapy and their usual outpatient clinical care. The primary outcome measure was change in HbA(1c) after one year of treatment. At enrolment, mean (standard deviation) HbA(1c) was 9.48% (0.99) for the metformin group (n = 49) and 9.60% (0.86) for the placebo group (n = 51). Mean (95% confidence interval) baseline-adjusted differences after 12 months with metformin (n = 48) versus placebo (n = 50) were: HbA(1c), 0.13% (-0.19; 0.44), p = 0.422; Total daily insulin dose, -5.7 U/day (-8.6; -2.9), p<0.001; body weight, -1.74 kg (-3.32; -0.17), p = 0.030. Minor and overall major hypoglycaemia was not significantly different between treatments. Treatments were well tolerated.In patients with poorly controlled T1DM, adjunct metformin therapy did not provide any improvement of glycaemic control after one year. Nevertheless, adjunct metformin treatment was associated with sustained reductions of insulin dose and body weight. Further investigations into the potential cardiovascular-protective effects of metformin therapy in patients with T1DM are warranted.ClinicalTrials.gov NCT00118937
Lesion of the Cerebellar Noradrenergic Innervation Enhances the Harmaline-Induced Tremor in Rats
Abnormal synchronous activation of the glutamatergic olivo-cerebellar pathway has been suggested to be crucial for the harmaline-induced tremor. The cerebellum receives two catecholaminergic pathways: the dopaminergic pathway arising from the ventral tegmental area/substantia nigra pars compacta, and the noradrenergic one from the locus coeruleus. The aim of the present study was to examine a contribution of the cerebellar catecholaminergic innervations to the harmaline-induced tremor in rats. Rats were injected bilaterally into the cerebellar vermis with 6-hydroxydopamine (6-OHDA; 8Â Îźg/0.5Â Îźl) either alone or this treatment was preceded (30Â min earlier) by desipramine (15Â mg/kg ip). Harmaline was administered to animals in doses of 7.5 or 15Â mg/kg ip. Tremor of forelimbs was measured as a number of episodes during a 90-min observation. Rats were killed by decapitation 30 or 120Â min after harmaline treatment. The levels of dopamine, noradrenaline, serotonin, and their metabolites were measured by HPLC in the cerebellum, substantia nigra, caudateâputamen, and frontal cortex. 6-OHDA injected alone enhanced the harmaline-induced tremor. Furthermore, it decreased the noradrenaline level by ca. 40â80% in the cerebellum and increased the levels of serotonin and 5-HIAA in the caudateâputamen and frontal cortex in untreated and/or harmaline-treated animals. When 6-OHDA treatment was preceded by desipramine, it decreased dopaminergic transmission in some regions of the cerebellum while inducing its compensatory activation in others. The latter lesion did not markedly influence the tremor induced by harmaline. The present study indicates that noradrenergic innervation of the cerebellum interacts with cerebral serotonergic systems and plays an inhibitory role in the harmaline-induced tremor
Interactive effects of mGlu5 and 5-HT2A receptors on locomotor activity in mice
RationaleMetabotropic glutamate (mGlu) receptors have been suggested to play a role in neuropsychiatric disorders including schizophrenia, drug abuse, and depression. Because serotonergic hallucinogens increase glutamate release and mGlu receptors modulate the response to serotonin (5-HT)(2A) activation, the interactions between serotonin 5-HT(2A) receptors and mGlu receptors may prove to be important for our understanding of these diseases.ObjectiveWe tested the effects of the serotonergic hallucinogen and 5-HT(2A) agonist, 2,5-dimethoxy-4-methylamphetamine (DOM), and the selective 5-HT(2A) antagonist, M100907, on locomotor activity in the mouse behavioral pattern monitor (BPM) in mGlu5 wild-type (WT) and knockout (KO) mice on a C57 background.ResultsBoth male and female mGlu5 KO mice showed locomotor hyperactivity and diminished locomotor habituation compared with their WT counterparts. Similarly, the mGlu5-negative allosteric modulator 2-methyl-6-(phenylethynyl)pyridine (MPEP) also increased locomotor hyperactivity, which was absent in mGlu5 KO mice. The locomotor hyperactivity in mGlu5 receptor KO mice was potentiated by DOM (0.5 mg/kg, subcutaneously (SC)) and attenuated by M100907 (1.0 mg/kg, SC). M100907 (0.1 mg/kg, SC) also blocked the hyperactivity induced by MPEP.ConclusionsThese studies demonstrated that loss of mGlu5 receptor activity either pharmacologically or through gene deletion leads to locomotor hyperactivity in mice. Additionally, the gene deletion of mGlu5 receptors increased the behavioral response to the 5-HT(2A) agonist DOM, suggesting that mGlu5 receptors either mitigate the behavioral effects of 5-HT(2A) hallucinogens or that mGlu5 KO mice show an increased sensitivity to 5-HT(2A) agonists. Taken together, these studies indicate a functional interaction between mGlu5 and 5-HT(2A) receptors
Selective mGluR1 Antagonist EMQMCM Inhibits the Kainate-Induced Excitotoxicity in Primary Neuronal Cultures and in the Rat Hippocampus
Abundant evidence suggests that indirect inhibitory modulation of glutamatergic transmission, via metabotropic glutamatergic receptors (mGluR), may induce neuroprotection. The present study was designed to determine whether the selective antagonist of mGluR1 (3-ethyl-2-methyl-quinolin-6-yl)-(4-methoxy-cyclohexyl)-methanone methanesulfonate (EMQMCM), showed neuroprotection against the kainate (KA)-induced excitotoxicity in vitro and in vivo. In in vitro studies on mouse primary cortical and hippocampal neuronal cultures, incubation with KA (150Â ÎźM) induced strong degeneration [measured as lactate dehydrogenase (LDH) efflux] and apoptosis (measured as caspase-3 activity). EMQMCM (0.1â100Â ÎźM) added 30Â min to 6Â h after KA, significantly attenuated the KA-induced LDH release and prevented the increase in caspase-3 activity in the cultures. Those effects were dose- and time-dependent. In in vivo studies KA (2.5Â nmol/1Â Îźl) was unilaterally injected into the rat dorsal CA1 hippocampal region. Degeneration was calculated by counting surviving neurons in the CA pyramidal layer using stereological methods. It was found that EMQMCM (5â10Â nmol/1Â Îźl) injected into the dorsal hippocampus 30Â min, 1Â h, or 3Â h (the higher dose only) after KA significantly prevented the KA-induced neuronal degeneration. In vivo microdialysis studies in rat hippocampus showed that EMQMCM (100Â ÎźM) significantly increased Îł-aminobutyric acid (GABA) and decreased glutamate release. When perfused simultaneously with KA, EMQMCM substantially increased GABA release and prevented the KA-induced glutamate release. The obtained results indicate that the mGluR1 antagonist, EMQMCM, may exert neuroprotection against excitotoxicity after delayed treatment (30Â min to 6Â h). The role of enhanced GABAergic transmission in the neuroprotection is postulated
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