987 resultados para single event upset


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Cardiovascular event rates have been shown to increase substantially with the number of symptomatic disease locations. We sought to assess the risk profile, management and subsequent event rates of polyvascular disease patients. Consecutive outpatients were assessed for atherosclerotic risk factors and medications in the REACH Registry. A total of 19,117 symptomatic patients in Europe completed a 2-year follow-up: 77.2% with single arterial bed disease (coronary artery or cerebrovascular or peripheral arterial disease) and 22.8% with polyvascular disease (>/= 1 disease location). Polyvascular disease patients were older (68.5 +/- 9.4 vs 66.3 +/- 9.9 years, p < 0.0001), more often current or former smokers (64.9% vs 58.7%, p < 0.0001), and more often suffered from hypertension (59.5% vs 46.6%, p < 0.0001) and diabetes (34.5% vs 25.9%, p < 0.0001) than single arterial bed disease patients. Despite more intense medical therapy, risk factors (smoking, hypertension, low fasting glucose, and low fasting total cholesterol) were less often controlled in polyvascular disease patients. This was associated with substantially more events over 2 years compared with single arterial bed disease patients (cMACCE [cardiovascular death/non-fatal stroke/non-fatal MI] odds ratio, 1.63 [95% CI, 1.45-1.83], p < 0.0001). In conclusion, polyvascular disease patients have more cardiovascular risk factors, and the prognosis for these patients is significantly worse than for patients with single arterial bed disease. This suggests a need to improve detection and consequent medical treatment of polyvascular disease.

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Abstract Objective: To evaluate the effectiveness of human recombinant activated factor VII (rhFVIIa, NovoSeven) in avoiding hysterectomy postpartum in the management of severe postpartum hemorrhage (PPH). Methods: We performed a prospective cohort study at our university tertiary care center. Patients with severe post partum hemorrhage (blood loss >2000 mL) and failed medical and uterus-preserving surgical management, were treated with intravenous bolus administration of rhVIIa. Main outcome measures were cessation of bleeding, postpartum hysterectomy and thromboembolic events. Results: In 20/22 patients included, PPH was caused primarily by uterine atony, including 7 (32%) with additional lower genital tract lesion; in two women, it was due to pathologic placentation (placenta increta, 9%). One case of amniotic fluid embolism and one woman with uterine inversion were included. Recombinant hFVIIa was successful in stopping the PPH and in preventing a hysterectomy in 20/22 women (91%). The remaining two patients with persistent bleeding despite rhFVIIa treatment, who underwent postpartum hysterectomy, had placenta increta. No thromboembolic event was noticed. Conclusions: This study describes the largest single center series of rhFVIIa treatment for fertility preservation in severe postpartum hemorrhage published to date. Our data suggest that administration of rhFVIIa is effective in avoiding postpartum hysterectomy after conservative medical and surgical measures have failed. Although randomized studies are lacking, rhFVIIa should be considered as a second-line therapeutic option of life-threatening postpartal bleeding, in particular if preservation of fertility is warranted and hysterectomy is to be avoided.

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PURPOSE: The aim of this paper is to demonstrate that computed tomography (CT) and three-dimensional (3D) CT imaging techniques can be useful tools for evaluating gunshot wounds of the skull in forensic medicine. Three purposes can be achieved: (1) identifying and recognising the bullet entrance wound - and exit wound, if present; (2) recognising the bullet's intracranial course by studying damage to bone and brain tissue; (3) suggesting hypotheses as to the dynamics of the event. MATERIALS AND METHODS: Ten cadavers of people who died of a fatal head injury caused by a single gunshot were imaged with total-body CT prior to conventional autoptic examination. Three-dimensional-CT reconstructions were obtained with the volume-rendering technique, and data were analysed by two independent observers and compared with autopsy results. RESULTS: In our experience, CT analysis and volumetric reconstruction techniques allowed the identification of the bullet entrance and exit wounds and intracranial trajectory, as well as helping to formulate a hypothesis on the extracranial trajectory to corroborate circumstantial evidence. CONCLUSIONS: CT imaging techniques are excellent tools for addressing the most important questions of forensic medicine in the case of gunshot wounds of the skull, with results as good as (or sometimes better than) traditional autoptic methods.

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Searching for the neural correlates of visuospatial processing using functional magnetic resonance imaging (fMRI) is usually done in an event-related framework of cognitive subtraction, applying a paradigm comprising visuospatial cognitive components and a corresponding control task. Besides methodological caveats of the cognitive subtraction approach, the standard general linear model with fixed hemodynamic response predictors bears the risk of being underspecified. It does not take into account the variability of the blood oxygen level-dependent signal response due to variable task demand and performance on the level of each single trial. This underspecification may result in reduced sensitivity regarding the identification of task-related brain regions. In a rapid event-related fMRI study, we used an extended general linear model including single-trial reaction-time-dependent hemodynamic response predictors for the analysis of an angle discrimination task. In addition to the already known regions in superior and inferior parietal lobule, mapping the reaction-time-dependent hemodynamic response predictor revealed a more specific network including task demand-dependent regions not being detectable using the cognitive subtraction method, such as bilateral caudate nucleus and insula, right inferior frontal gyrus and left precentral gyrus.

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RATIONALE: Olanzapine is an atypical antipsychotic drug with a more favourable safety profile than typical antipsychotics with a hitherto unknown topographic quantitative electroencephalogram (QEEG) profile. OBJECTIVES: We investigated electrical brain activity (QEEG and cognitive event related potentials, ERPs) in healthy subjects who received olanzapine. METHODS: Vigilance-controlled, 19-channel EEG and ERP in an auditory odd-ball paradigm were recorded before and 3 h, 6 h and 9 h after administration of either a single dose of placebo or olanzapine (2.5 mg and 5 mg) in ten healthy subjects. QEEG was analysed by spectral analysis and evaluated in nine frequency bands. For the P300 component in the odd-ball ERP, the amplitude and latency was analysed. Statistical effects were tested using a repeated-measurement analysis of variance. RESULTS: For the interaction between time and treatment, significant effects were observed for theta, alpha-2, beta-2 and beta-4 frequency bands. The amplitude of the activity in the theta band increased most significantly 6 h after the 5-mg administration of olanzapine. A pronounced decrease of the alpha-2 activity especially 9 h after 5 mg olanzapine administration could be observed. In most beta frequency bands, and most significantly in the beta-4 band, a dose-dependent decrease of the activity beginning 6 h after drug administration was demonstrated. Topographic effects could be observed for the beta-2 band (occipital decrease) and a tendency for the alpha-2 band (frontal increase and occipital decrease), both indicating a frontal shift of brain electrical activity. There were no significant changes in P300 amplitude or latency after drug administration. Conclusion: QEEG alterations after olanzapine administration were similar to EEG effects gained by other atypical antipsychotic drugs, such as clozapine. The increase of theta activity is comparable to the frequency distribution observed for thymoleptics or antipsychotics for which treatment-emergent somnolence is commonly observed, whereas the decrease of beta activity observed after olanzapine administration is not characteristic for these drugs. There were no clear signs for an increased cerebral excitability after a single-dose administration of 2.5 mg and 5 mg olanzapine in healthy controls.

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In this randomized, double-blind, multicenter study, patients whose blood pressure (BP) was uncontrolled by monotherapy were switched directly to amlodipine/valsartan 5/160 mg (n=443) or 10/160 mg (n=451). After 16 weeks, BP control (levels <140/90 mm Hg or <130/80 mm Hg for diabetics) was achieved in 72.7% (95% confidence interval [CI], 68.6-76.9) of patients receiving amlodipine/valsartan 5/160 mg and in 74.8% (95% CI, 70.8-78.9) receiving amlodipine/valsartan 10/160 mg. Incremental reductions from baseline in mean sitting systolic and diastolic BP were significantly greater with the higher dose (20.0+/-0.7 vs 17.5+/-0.7 mm Hg; P=.0003 and 11.6+/-0.4 vs 10.4+/-0.4 mm Hg; P=.0046). Incremental BP reductions were also achieved with both regimens irrespective of previous monotherapy, hypertension severity, diabetic status, body mass index, and age. Peripheral edema was the most frequent adverse event. These results provide support for the BP-lowering benefits of complementary antihypertensive therapy with amlodipine and valsartan in patients with hypertension uncontrolled by previous monotherapy.

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The present study shows that different neural activity during mental imagery and abstract mentation can be assigned to well-defined steps of the brain's information-processing. During randomized visual presentation of single, imagery-type and abstract-type words, 27 channel event-related potential (ERP) field maps were obtained from 25 subjects (sequence-divided into a first and second group for statistics). The brain field map series showed a sequence of typical map configurations that were quasi-stable for brief time periods (microstates). The microstates were concatenated by rapid map changes. As different map configurations must result from different spatial patterns of neural activity, each microstate represents different active neural networks. Accordingly, microstates are assumed to correspond to discrete steps of information-processing. Comparing microstate topographies (using centroids) between imagery- and abstract-type words, significantly different microstates were found in both subject groups at 286–354 ms where imagery-type words were more right-lateralized than abstract-type words, and at 550–606 ms and 606–666 ms where anterior-posterior differences occurred. We conclude that language-processing consists of several, well-defined steps and that the brain-states incorporating those steps are altered by the stimuli's capacities to generate mental imagery or abstract mentation in a state-dependent manner.

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Cognitive event-related potentials (ERPs) are widely employed in the study of dementive disorders. The morphology of averaged response is known to be under the influence of neurodegenerative processes and exploited for diagnostic purposes. This work is built over the idea that there is additional information in the dynamics of single-trial responses. We introduce a novel way to detect mild cognitive impairment (MCI) from the recordings of auditory ERP responses. Using single trial responses from a cohort of 25 amnestic MCI patients and a group of age-matched controls, we suggest a descriptor capable of encapsulating single-trial (ST) response dynamics for the benefit of early diagnosis. A customized vector quantization (VQ) scheme is first employed to summarize the overall set of ST-responses by means of a small-sized codebook of brain waves that is semantically organized. Each ST-response is then treated as a trajectory that can be encoded as a sequence of code vectors. A subject's set of responses is consequently represented as a histogram of activated code vectors. Discriminating MCI patients from healthy controls is based on the deduced response profiles and carried out by means of a standard machine learning procedure. The novel response representation was found to improve significantly MCI detection with respect to the standard alternative representation obtained via ensemble averaging (13% in terms of sensitivity and 6% in terms of specificity). Hence, the role of cognitive ERPs as biomarker for MCI can be enhanced by adopting the delicate description of our VQ scheme.

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Calmodulin (CaM) is a ubiquitous Ca(2+) buffer and second messenger that affects cellular function as diverse as cardiac excitability, synaptic plasticity, and gene transcription. In CA1 pyramidal neurons, CaM regulates two opposing Ca(2+)-dependent processes that underlie memory formation: long-term potentiation (LTP) and long-term depression (LTD). Induction of LTP and LTD require activation of Ca(2+)-CaM-dependent enzymes: Ca(2+)/CaM-dependent kinase II (CaMKII) and calcineurin, respectively. Yet, it remains unclear as to how Ca(2+) and CaM produce these two opposing effects, LTP and LTD. CaM binds 4 Ca(2+) ions: two in its N-terminal lobe and two in its C-terminal lobe. Experimental studies have shown that the N- and C-terminal lobes of CaM have different binding kinetics toward Ca(2+) and its downstream targets. This may suggest that each lobe of CaM differentially responds to Ca(2+) signal patterns. Here, we use a novel event-driven particle-based Monte Carlo simulation and statistical point pattern analysis to explore the spatial and temporal dynamics of lobe-specific Ca(2+)-CaM interaction at the single molecule level. We show that the N-lobe of CaM, but not the C-lobe, exhibits a nano-scale domain of activation that is highly sensitive to the location of Ca(2+) channels, and to the microscopic injection rate of Ca(2+) ions. We also demonstrate that Ca(2+) saturation takes place via two different pathways depending on the Ca(2+) injection rate, one dominated by the N-terminal lobe, and the other one by the C-terminal lobe. Taken together, these results suggest that the two lobes of CaM function as distinct Ca(2+) sensors that can differentially transduce Ca(2+) influx to downstream targets. We discuss a possible role of the N-terminal lobe-specific Ca(2+)-CaM nano-domain in CaMKII activation required for the induction of synaptic plasticity.

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Purpose: To assess the 5-year survival rate and number of technical, biologic, and esthetic complications involving implant abutments. Materials and Methods: Electronic (Medline) and hand searches were performed to assess studies on metal and ceramic implant abutments. Relevant data from a previous review were included. Two reviewers independently extracted the data. Failure and complication rates were analyzed, and estimates of 5-year survival proportions were calculated from the relationship between event rate and survival function. Multivariable robust Poisson regression was used to compare abutment characteristics. Results: The search yielded 1,558 titles and 274 abstracts. Twenty-four studies were selected for data analysis. The survival rate for ceramic abutments was 97.5% (95% confidence interval [CI]): 89.6% to 99.4%) and 97.6% (95% CI: 96.2% to 98.5%) for metal abutments. The overall 5-year rate for technical complications was 11.8% (95% CI: 8.5% to 16.3%), 8.9% (95% CI: 4.3% to 17.7%) for ceramic and 12.0% (95% CI: 8.5% to 16.8%) for metal abutments. Biologic complications occurred with an overall rate of 6.4% (95% CI: 3.3% to 12.0%), 10.4% (95% CI: 1.9% to 46.7%) for ceramic, and 6.1% (95% CI: 3.1% to 12.0%) for metal abutments. Conclusions: The present meta-analysis on single-implant prostheses presents high survival rates of single implants, abutments, and prostheses after 5 years of function. No differences were found for the survival and failure rates of ceramic and metal abutments. No significant differences were found for technical, biologic, and esthetic complications of internally and externally connected abutments.

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OBJECTIVE: To develop a behavioural observation method to simultaneously assess distractors and communication/teamwork during surgical procedures through direct, on-site observations; to establish the reliability of the method for long (>3 h) procedures. METHODS: Observational categories for an event-based coding system were developed based on expert interviews, observations and a literature review. Using Cohen's κ and the intraclass correlation coefficient, interobserver agreement was assessed for 29 procedures. Agreement was calculated for the entire surgery, and for the 1st hour. In addition, interobserver agreement was assessed between two tired observers and between a tired and a non-tired observer after 3 h of surgery. RESULTS: The observational system has five codes for distractors (door openings, noise distractors, technical distractors, side conversations and interruptions), eight codes for communication/teamwork (case-relevant communication, teaching, leadership, problem solving, case-irrelevant communication, laughter, tension and communication with external visitors) and five contextual codes (incision, last stitch, personnel changes in the sterile team, location changes around the table and incidents). Based on 5-min intervals, Cohen's κ was good to excellent for distractors (0.74-0.98) and for communication/teamwork (0.70-1). Based on frequency counts, intraclass correlation coefficient was excellent for distractors (0.86-0.99) and good to excellent for communication/teamwork (0.45-0.99). After 3 h of surgery, Cohen's κ was 0.78-0.93 for distractors, and 0.79-1 for communication/teamwork. DISCUSSION: The observational method developed allows a single observer to simultaneously assess distractors and communication/teamwork. Even for long procedures, high interobserver agreement can be achieved. Data collected with this method allow for investigating separate or combined effects of distractions and communication/teamwork on surgical performance and patient outcomes.

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A search is presented for the production of new heavy quarks that decay to a Z boson and a third-generation Standard Model quark. In the case of a new charge +2/3 quark (T), the decay targeted is T → Zt, while the decay targeted for a new charge −1/3 quark (B) is B → Zb. The search is performed with a dataset corresponding to 20.3 fb−1 of pp collisions at √ s = 8TeV recorded in 2012 with the ATLAS detector at the CERN Large Hadron Collider. Selected events contain a high transverse momentum Z boson candidate reconstructed from a pair of oppositely charged same-flavor leptons (electrons or muons), and are analyzed in two channels defined by the absence or presence of a third lepton. Hadronic jets, in particular those with properties consistent with the decay of a b-hadron, are also required to be present in selected events. Different requirements are made on the jet activity in the event in order to enhance the sensitivity to either heavy quark pair production mediated by the strong interaction, or single production mediated by the electroweak interaction. No significant excess of events above the Standard Model expectation is observed, and lower limits are derived on the mass of vector-like T and B quarks under various branching ratio hypotheses, as well as upper limits on the agnitude of electroweak coupling parameters.

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PURPOSE Rituximab maintenance therapy has been shown to improve progression-free survival in patients with follicular lymphoma; however, the optimal duration of maintenance treatment remains unknown. PATIENTS AND METHODS Two hundred seventy patients with untreated, relapsed, stable, or chemotherapy-resistant follicular lymphoma were treated with four doses of rituximab monotherapy in weekly intervals (375 mg/m(2)). Patients achieving at least a partial response were randomly assigned to receive maintenance therapy with one infusion of rituximab every 2 months, either on a short-term schedule (four administrations) or a long-term schedule (maximum of 5 years or until disease progression or unacceptable toxicity). The primary end point was event-free survival (EFS). Progression-free survival, overall survival (OS), and toxicity were secondary end points. Comparisons between the two arms were performed using the log-rank test for survival end points. RESULTS One hundred sixty-five patients were randomly assigned to the short-term (n = 82) or long-term (n = 83) maintenance arms. Because of the low event rate, the final analysis was performed after 95 events had occurred, which was before the targeted event number of 99 had been reached. At a median follow-up period of 6.4 years, the median EFS was 3.4 years (95% CI, 2.1 to 5.3) in the short-term arm and 5.3 years (95% CI, 3.5 to not available) in the long-term arm (P = .14). Patients in the long-term arm experienced more adverse effects than did those in the short-term arm, with 76% v 50% of patients with at least one adverse event (P < .001), five versus one patient with grade 3 and 4 infections, and three versus zero patients discontinuing treatment because of unacceptable toxicity, respectively. There was no difference in OS between the two groups. CONCLUSION Long-term rituximab maintenance therapy does not improve EFS, which was the primary end point of this trial, or OS, and was associated with increased toxicity.

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Objective: The authors quantified nonverbal synchrony—the coordination of patient's and therapist's movement—in a random sample of same-sex psychotherapy dyads. The authors contrasted nonverbal synchrony in these dyads with a control condition and assessed its association with session-level and overall psychotherapy outcome. Method: Using an automated objective video analysis algorithm (Motion Energy Analysis; MEA), the authors calculated nonverbal synchrony in (n = 104) videotaped psychotherapy sessions from 70 Caucasian patients (37 women, 33 men, mean age = 36.5 years, SD = 10.2) treated at an outpatient psychotherapy clinic. The sample was randomly drawn from an archive (N = 301) of routinely videotaped psychotherapies. Patients and their therapists assessed session impact with self-report postsession questionnaires. A battery of pre- and postsymptomatology questionnaires measured therapy effectiveness. Results: The authors found that nonverbal synchrony is higher in genuine interactions contrasted with pseudointeractions (a control condition generated by a specifically designed shuffling procedure). Furthermore, nonverbal synchrony is associated with session-level process as well as therapy outcome: It is increased in sessions rated by patients as manifesting high relationship quality and in patients experiencing high self-efficacy. Higher nonverbal synchrony characterized psychotherapies with higher symptom reduction. Conclusions: The results suggest that nonverbal synchrony embodies the patients' self-reported quality of the relationship and further variables of therapy process. This hitherto overlooked facet of therapeutic relationships might prove useful as an indicator of therapy progress and outcome. (PsycINFO Database Record (c) 2015 APA, all rights reserved)