997 resultados para R-curve
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OBJECTIVES: The aim of this study was to evaluate new electrocardiographic (ECG) criteria for discriminating between incomplete right bundle branch block (RBBB) and the Brugada types 2 and 3 ECG patterns. BACKGROUND: Brugada syndrome can manifest as either type 2 or type 3 pattern. The latter should be distinguished from incomplete RBBB, present in 3% of the population. METHODS: Thirty-eight patients with either type 2 or type 3 Brugada pattern that were referred for an antiarrhythmic drug challenge (AAD) were included. Before AAD, 2 angles were measured from ECG leads V(1) and/or V(2) showing incomplete RBBB: 1) α, the angle between a vertical line and the downslope of the r'-wave, and 2) β, the angle between the upslope of the S-wave and the downslope of the r'-wave. Baseline angle values, alone or combined with QRS duration, were compared between patients with negative and positive results on AAD. Receiver-operating characteristic curves were constructed to identify optimal discriminative cutoff values. RESULTS: The mean β angle was significantly smaller in the 14 patients with negative results on AAD compared to the 24 patients with positive results on AAD (36 ± 20° vs. 62 ± 20°, p < 0.01). Its optimal cutoff value was 58°, which yielded a positive predictive value of 73% and a negative predictive value of 87% for conversion to type 1 pattern on AAD; α was slightly less sensitive and specific compared with β. When the angles were combined with QRS duration, it tended to improve discrimination. CONCLUSIONS: In patients with suspected Brugada syndrome, simple ECG criteria can enable discrimination between incomplete RBBB and types 2 and 3 Brugada patterns.
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No estudo aqui apresentado, aplicou-se um modelo de rede neural multicamadas para o apreçamento de calls sobre taxa de câmbio R$/US$, negociadas na Bolsa de Valores, Mercadorias & Futuros de São Paulo (BM&FBovespa), para o período de janeiro de 2004 a dezembro de 2007. A partir dos preços efetivamente praticados no mercado, comparou-se o desempenho entre essa técnica e o modelo de Black, utilizando-se métricas usuais de erro e testes estatísticos. Os resultados obtidos revelaram, em geral, a melhor adequação do modelo de inteligência artificial, em comparação ao modelo de Black, nos diferentes graus de moneyness.
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Teicoplanin is frequently administered to treat Gram-positive infections in pediatric patients. However, not enough is known about the pharmacokinetics (PK) of teicoplanin in children to justify the optimal dosing regimen. The aim of this study was to determine the population PK of teicoplanin in children and evaluate the current dosage regimens. A PK hospital-based study was conducted. Current dosage recommendations were used for children up to 16 years of age. Thirty-nine children were recruited. Serum samples were collected at the first dose interval (1, 3, 6, and 24 h) and at steady state. A standard 2-compartment PK model was developed, followed by structural models that incorporated weight. Weight was allowed to affect clearance (CL) using linear and allometric scaling terms. The linear model best accounted for the observed data and was subsequently chosen for Monte Carlo simulations. The PK parameter medians/means (standard deviation [SD]) were as follows: CL, [0.019/0.023 (0.01)] × weight liters/h/kg of body weight; volume, 2.282/4.138 liters (4.14 liters); first-order rate constant from the central to peripheral compartment (Kcp), 0.474/3.876 h(-1) (8.16 h(-1)); and first-order rate constant from peripheral to central compartment (Kpc), 0.292/3.994 h(-1) (8.93 h(-1)). The percentage of patients with a minimum concentration of drug in serum (Cmin) of <10 mg/liter was 53.85%. The median/mean (SD) total population area under the concentration-time curve (AUC) was 619/527.05 mg · h/liter (166.03 mg · h/liter). Based on Monte Carlo simulations, only 30.04% (median AUC, 507.04 mg · h/liter), 44.88% (494.1 mg · h/liter), and 60.54% (452.03 mg · h/liter) of patients weighing 50, 25, and 10 kg, respectively, attained trough concentrations of >10 mg/liter by day 4 of treatment. The teicoplanin population PK is highly variable in children, with a wider AUC distribution spread than for adults. Therapeutic drug monitoring should be a routine requirement to minimize suboptimal concentrations. (This trial has been registered in the European Clinical Trials Database Registry [EudraCT] under registration number 2012-005738-12.).
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Manuel O, Pascual M, Perrottet N, Lamoth F, Venetz J-P, Decosterd LA, Buclin T, Meylan PR. Ganciclovir exposure under a 450 mg daily dosage of valganciclovir for cytomegalovirus prevention in kidney transplantation: a prospective study. Clin Transplant 2010: 24: 794-800. Abstract: This prospective study aimed at determining the ganciclovir exposure observed under a daily dosage of 450 mg valganciclovir routinely applied to kidney transplant recipients with a GFR above 25 mL/min at risk for cytomegalovirus (CMV) disease. Ganciclovir levels at trough (C(trough) ) and at peak (C(3 h) ) were measured monthly. Ganciclovir exposure (area under the curve [AUC(0-24) ]) was estimated using Bayesian non-linear mixed-effect modeling (NONMEM). Thirty-six patients received 450 mg of valganciclovir daily for three months. Median ganciclovir C(3 h) was 3.9 mg/L (range: 1.3-7.1), and C(trough) was 0.4 mg/L (range 0.1-2.7). Median AUC(0-24) of ganciclovir was 59.3 mg h/L (39.0-85.3) in patients with GFR(MDRD) 26-39 mL/min, 35.8 mg h/L (24.9-55.8) in patients with GFR(MDRD) 40-59 mL/min, and 29.6 mg h/L (22.0-43.2) in patients with GFR(MDRD) ≥ 60 mL/min. No major differences in adverse events according to ganciclovir exposure were observed. CMV viremia was not detected during prophylaxis. After discontinuing prophylaxis, CMV viremia was seen in 8/36 patients (22%), and 4/36 patients (11%) developed CMV disease. Ganciclovir exposure after administration of valganciclovir 450 mg daily in recipients with GFR ≥60 mL/min was comparable to those previously reported with oral ganciclovir. A routine daily dose of 450 mg valganciclovir appears to be acceptable for CMV prophylaxis in most kidney transplant recipients.
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A four compartment model of the cardiovascular system is developed. To allow for easy interpretation and to minimise the number of parameters, an effort was made to keep the model as simple as possible. A sensitivity analysis is first carried out to determine which are the most important model parameters to characterise the blood pressure signal. A four stage process is then described which accurately determines all parameter values. This process is applied to data from three patients and good agreement is shown in all cases.
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ABSTRACT The interorganizational cooperation, through joint efforts with various actors, allows the high-tech companies to complement resources, especially in R&D projects. Collaborative projects have been identified in many studies as an important strategy to produce complex products and services in uncertain and competitive environments. Thus, this research aims at deepening the understanding of how the development dynamics of a collaborative R&D project in an industry of high technology occur. In order to achieve the proposed objective, the R&D project of the first microcontroller in the Brazilian semiconductor industry was defined as the object of analysis. The empirical choice is justified by the uniqueness of the case, besides bringing a diversity of actors and a level of complementarity of resources that were significant to the success of the project. Given the motivation to know who the actors were and what the main forms of interorganizational coordination were used in this project, interviews were carried out and a questionnaire was also made, besides other documents related to the project. The results presented show a network of nine actors and their roles in the interorganizational collaboration process, as well as the forms of social and temporal overlapping, used in the coordination of collective efforts. Focusing on the mechanisms of temporal and social integration highlighted throughout the study, the inclusion of R&D projects in the typology for interorganizational projects is proposed in this paper, which was also proposed by Jones and Lichtenstein (2008).
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Purpose: To analyse prospectively the long-term results of Gamma Knife surgery (GKS) in patients with trigeminal neuralgia secondary to megadolichobasilar artery (MBA). Methods: Between December 1992 and November 2010, 33 consecutive patients presenting with ITN secondary to MBA were operated by GKS and followed prospectively in Timone University Hospital. The follow up is at least of 1 year in 29 patients. The median age was 74.90 years (range 51 to 90). The GKS typically was performed using MR and CT imaging guidance and a single 4 mm isocenter. The median of the prescription dose (at the 100%) was 90 Gy (range 80 to 90). The target was placed on the cisternal portion of the Vth nerve. Clinical and dosimetric parameters were analyzed. GKS was the first surgical procedure in 23 patients (79.31%). Results: The median follow- up period was 46.12 months (range 12.95 to 157.93). All the 29 patients (100%) were initially pain free in a median time of 13.5 days (range 0 to 240). The probability of remaining pain free at 0.5, 1, 2 years was 93.1%, 79.3% and 75.7% respectively, reaching at this time the flat part of the curve. Seven patients (24.13%) experienced a recurrence with a median delay of 10.75 months (range 3.77 to 12.62). The actuarial rate of recurrence was not higher than in our population with essential TN although atypical pain was associated with a much higher risk of recurrence (HR= 6.92, p= 0.0117). The hypoesthesia actuarial rates at 0.5 years was 4.3% and at 1 year reach 13% and remains stable till 12 years with a median delay of onset of 7 (5, 12) months. Female patients had a statistically much lower probability of developing a facial numbness (p of 0.03). No patient reported a bothersome hypoesthesia. Conclusion: Retrogaserian, high dose GKS, turned out to be very safe with only 13.04% hypoesthesia, which was never disabling (0%), while achieving high quality pain control. The majority of the patients demonstrated a prolonged effect of radiosurgery in absence of any trigeminal nerve disturbance.
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[Acte royal. 1715-10-04. Paris]
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BACKGROUND: The Pulmonary Embolism Severity Index (PESI) estimates the risk of 30-day mortality in patients with acute pulmonary embolism (PE). We constructed a simplified version of the PESI. METHODS: The study retrospectively developed a simplified PESI clinical prediction rule for estimating the risk of 30-day mortality in a derivation cohort of Spanish outpatients. Simplified and original PESI performances were compared in the derivation cohort. The simplified PESI underwent retrospective external validation in an independent multinational cohort (Registro Informatizado de la Enfermedad Tromboembólica [RIETE] cohort) of outpatients. RESULTS: In the derivation data set, univariate logistic regression of the original 11 PESI variables led to the removal of variables that did not reach statistical significance and subsequently produced the simplified PESI that contained the variables of age, cancer, chronic cardiopulmonary disease, heart rate, systolic blood pressure, and oxyhemoglobin saturation levels. The prognostic accuracy of the original and simplified PESI scores did not differ (area under the curve, 0.75 [95% confidence interval (CI), 0.69-0.80]). The 305 of 995 patients (30.7%) who were classified as low risk by the simplified PESI had a 30-day mortality of 1.0% (95% CI, 0.0%-2.1%) compared with 10.9% (8.5%-13.2%) in the high-risk group. In the RIETE validation cohort, 2569 of 7106 patients (36.2%) who were classified as low risk by the simplified PESI had a 30-day mortality of 1.1% (95% CI, 0.7%-1.5%) compared with 8.9% (8.1%-9.8%) in the high-risk group. CONCLUSION: The simplified PESI has similar prognostic accuracy and clinical utility and greater ease of use compared with the original PESI.
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SAP R/3 és un software estàndard de gestió empresarial que engloba tots els processos iactivitats d’una companyia i permet el disseny de l’aplicació a les necessitats de l’empresa.Diferents avantatges, com ara disposar d’una base de dades única, han fet escollir aquestsistema a una empresa del sector metal•lúrgic com a eina de gestió:Aquest projecte té com a objecte la implantació de dos dels mòduls que inclou el sistemaSAP R/3, concretament el mòdul SD (Sales and Distribution), amb el qual es controlen lesvendes de l’empresa, i el mòdul MM (Material Management), mòdul amb el qual es controlatot el que fa referència als materials, la gestió d’estocs i tota la gestió de compres del’empresa