Encerramento Percutâneo de Shunts Interauriculares: Experiência de uma Década de um Centro Terciário

INTRODUCTION: Atrial septal defects (ASD) are among the most common congenital anomalies and account for 10% of congenital heart disease in the pediatric age-group and 30% in adults. Closure is indicated when there is evidence of hemodynamic significance or after a paradoxical embolic event. Ten years ago, percutaneous closure became the treatment of choice in our center for all patients with a clear indication and favorable anatomy. In this paper we report the experience of this first decade. OBJECTIVE: To assess the short- and long-term results of our ten-year experience with percutaneous closure of atrial septal defects. METHODS: We studied retrospectively all patients with ASD treated with a percutaneous approach between November 1998 and December 2008. The pediatric age-group consisted of patients younger than 19 years old. Demographic data, clinical indications, minor and major complication rates, success rate and long-term outcome were assessed. RESULTS: In the first ten years of experience 510 patients, of whom 166 were in the pediatric group, were treated in our center by a team of adult and pediatric cardiologists. The overall success rate of the procedure was 98% (97.5% in ASD and 99.5% in patent foramen ovale (PFO). The minor complication rate was 3% (3.4% in ASD and 2% in PFO). The most frequent complication was supraventricular tachycardia. The major complication rate was 1.2% (0.6% in ASD and 2% in PFO). Two patients developed cardiac tamponade due to hemopericardium that was resolved by pericardiocentesis, without need for surgery. One patient had an arterial pseudoaneurysm corrected by vascular surgery. There was no device embolization and no need for urgent surgery in this population. During follow-up two patients had recurrence of ischemic stroke, one had a transient ischemic attack and another had a hemorrhagic stroke. Mortality was 0.6% (0.6% in ASD and 0.5% in PFO). There were no in-hospital deaths. During follow-up there were two deaths, both in the adult group. DISCUSSION AND CONCLUSION: In this population the success rate was high and most of the complications were minor. The results of this collaboration between adult and pediatric cardiologists in the first ten years of activity confirm the safety and efficacy of percutaneous closure of septal defects, when there is careful patient selection and a standardized technique.

Coarctação Isolada da Aorta: Experiência em 100 Doentes Consecutivos

INTRODUCTION: Coarctation of the aorta (CoA) is a stenosis usually located in the descending aorta. Treatment consists of surgical or percutaneous removal of the obstruction and presents excellent immediate results but significant residual problems often persist. OBJECTIVES: To describe the presentation, treatment and long-term evolution of a population of 100 unselected consecutive patients with isolated CoA in a single pediatric cardiology center. METHODS: This was a retrospective study of all patients with isolated CoA treated during4 the last 21 years (1987-2008). RESULTS: The patients (n=100, 68.3% male) were diagnosed at a median age of 94 days (1 day to 16 years). The clinical presentation differed between patients aged less or more than one year, the former presenting with heart failure and the latter being asymptomatic with evidence of hypertension (88 and 63%, respectively; p < 0.01). Treatment, a median of 8 days after diagnosis, was surgical in 79 cases (20 end-to-end anastomosis, 31 subclavian flap, 28 patch) and percutaneous in the remaining 21 (15 balloon angioplasty, 6 with stenting). The mean age of surgical patients was younger than in those treated percutaneously (3.4 vs. 7.5 years; p < 0.01). Immediate mortality was 2% and occurred in the surgical group. There was no late mortality, in a mean follow-up of 7.2 +/- 5.4 years. Recoarctation occurred in 8 patients (6 surgical, 2 percutaneous). There are 46 patients who currently have hypertension (19 at rest, 27 with effort), their median age at diagnosis being older than the others (23 vs. 995 days; p < 0.01). CONCLUSIONS: Isolated CoA has an excellent short-term prognosis but a significant incidence of long-term complications, and should thus no longer be seen as a simple obstruction in the descending aorta, but rather as a complex pathology that requires careful follow-up after treatment. Its potentially insidious presentation requires a high level of clinical suspicion, femoral pulse palpation during physical examination of newborns and older children being particularly important. Delay in treatment has an impact on late morbidity and mortality. Taking into account the data currently available on late and immediate results, the final choice of therapeutic technique depends on the patient's age, associated lesions and the experience of the medical-surgical team. Hypertension should be closely monitored in the follow-up of these patients, as well as its risk factors and complications.

Using data mining with time series data in short-term stocks prediction

Data Mining (DM) methods are being increasingly used in prediction with time series data, in addition to traditional statistical approaches. This paper presents a literature review of the use of DM with time series data, focusing on short- time stocks prediction. This is an area that has been attracting a great deal of attention from researchers in the field. The main contribution of this paper is to provide an outline of the use of DM with time series data, using mainly examples related with short-term stocks prediction. This is important to a better understanding of the field. Some of the main trends and open issues will also be introduced.

Hepatitis C in patients co-infected with human immunodeficiency virus. A review and experience of a Brazilian ambulatory

Hepatitis C virus (HCV) and human immunodeficiency virus (HIV) share the same transmission mechanisms. The prevalence of HCV in the HIV-infected population varies from region to region, throughout the world, depending on different exposure factors to both viruses. Co-infection with HIV accelerates the progression of the disease caused by HCV, appears to worsen the progression of the HIV infection and increases HCV transmission. Therefore, clinical management and treatment of HCV is a priority in medical facilities that receive HIV-infected patients. Clinical management of these patients involves specific diagnostic procedures and appropriately trained medical staff. The indication of treatment should meet specific clinical and laboratory criteria. There are a number of drugs currently available to treat hepatitis C in co-infected patients.

Head-Up Tilt Testing with Different Nitroglycerin Dosages: Experience in Elderly Patients with Unexplained Syncope

AIMS: Protocols using sublingual nitrates have been increasingly used to improve diagnostic accuracy of head-up tilt testing (HUT). Nevertheless, exaggerated responses to nitrates have been frequently described, particularly in elderly patients. The aim of this article is to evaluate, in an elderly population with unexplained syncope, whether the impact of sublingual nitroglycerin (NTG) used as a provocative agent is dose-dependent. METHODS AND RESULTS: One hundred and twenty consecutive elderly patients submitted to HUT using NTG after an asymptomatic drug-free phase were studied. Patients were divided into three groups according to the NTG dosage: 500, 375 and 250 microg. The test was considered positive when there was reproduction of symptoms with bradycardia and/or arterial hypotension. A gradual decrease in the blood pressure after NTG was considered an exaggerated response to nitrates. There were no differences in the clinical characteristics of the different subgroups. A positive test was obtained in 50% of the patients in each group. The rate of exaggerated responses was identical in all groups and ranged between 15 and 17%. CONCLUSION: In an elderly population with syncope of unknown origin submitted to HUT, the response to NTG is not dose-dependent, and no difference was found in the rate of exaggerated responses to nitrates with different NTG dosages.

TURTLE: Systems and technologies for deep ocean long term presence

This paper describes the TURTLE project that aim to develop sub-systems with the capability of deep-sea long-term presence. Our motivation is to produce new robotic ascend and descend energy efficient technologies to be incorporated in robotic vehicles used by civil and military stakeholders for underwater operations. TURTLE contribute to the sustainable presence and operations in the sea bottom. Long term presence on sea bottom, increased awareness and operation capabilities in underwater sea and in particular on benthic deeps can only be achieved through the use of advanced technologies, leading to automation of operation, reducing operational costs and increasing efficiency of human activity.

Lupus and Pregnancy. 15 Years of Experience in a Tertiary Center

This retrospective study was designed to evaluate the outcome of pregnancies in women diagnosed with systemic lupus erythematosus (SLE) followed in a tertiary fetal–maternal center. Data were collected from clinical charts between January 1993 and December 2007, with a total of 136 pregnancies (107 patients). Mean maternal age was 29 years, with the vast majority of patients being Caucasian. Most patients were in remission 6 months prior to pregnancy (93%) and the most frequently affected organs were the skin and joints. Renal lupus accounted for 14% of all cases. Twenty-nine percent of patients were positive for at least one antiphospholid antibody (aPL) and nearly 50% had positive SSa/SSb antibodies. All patients with positive aPL received low-dosage aspirin and low molecular- weight heparin (LMWH). There were no pregnancy complications in more than 50% of cases and hypertensive disease and intrauterine growth restriction were the most common adverse events. There were 125 live births, one neonatal death, eight miscarriages, and three medical terminations of pregnancy. Preterm delivery occurred in 25% of pregnancies. Our results are probably the conjoined result of a multidisciplinary approach together with a systematic management of SLE pregnancies, with most patients keeping their prior SLE medication combined with low-dosage aspirin and LMWH in the presence of aPL.

A multi-objective model for scheduling of short-term incentive-based demand response programs offered by electricity retailers

In this paper, we formulate the electricity retailers’ short-term decision-making problem in a liberalized retail market as a multi-objective optimization model. Retailers with light physical assets, such as generation and storage units in the distribution network, are considered. Following advances in smart grid technologies, electricity retailers are becoming able to employ incentive-based demand response (DR) programs in addition to their physical assets to effectively manage the risks of market price and load variations. In this model, the DR scheduling is performed simultaneously with the dispatch of generation and storage units. The ultimate goal is to find the optimal values of the hourly financial incentives offered to the end-users. The proposed model considers the capacity obligations imposed on retailers by the grid operator. The profit seeking retailer also has the objective to minimize the peak demand to avoid the high capacity charges in form of grid tariffs or penalties. The non-dominated sorting genetic algorithm II (NSGA-II) is used to solve the multi-objective problem. It is a fast and elitist multi-objective evolutionary algorithm. A case study is solved to illustrate the efficient performance of the proposed methodology. Simulation results show the effectiveness of the model for designing the incentive-based DR programs and indicate the efficiency of NSGA-II in solving the retailers’ multi-objective problem.

Drug Provocation Tests to Betalactam Antibiotics: Experience in a Paediatric Setting

Background: Few studies have been performed in children withs uspected betalactam allergy.We aimed to assess the role of the drug provocation test(DPT)with betalactams in a paediatric setting and to study the association between allergy to betalactam antibiotics and other allergic diseases. Methods:We included all the patients under 15 years old who were consecutively referred to the Immunoallergy Department, Dona Estefânia Hospital,Portugal(January 2002 to April 2008)for a compatible history of allergic reaction to betalactam. All were submitted to a DPT.Children were proposed to performs kintests(ST)to betalactam antibiotics followed by DPT. If they decline ST,a DPT with the culprit drug was performed. Results: We studied 161 children,60%were boys,with a median age of 5years old at the time of the DPT.Thirty-three patients(20.5%)had an immediate reaction and 33(20.5%)a non-immediate reaction. These verity of there porte dreactions was low in most cases. Skin tests to betalactams were performed in 47 children and were positive in 8.DPT was positive inonlyone(3.4%)of the patients skin tested and in 11(13.4%)of those not skin tested. These verity of the DPT reaction was low.Asthma and food allergy were associated with a positive DPT in the later group. Conclusions: DPT seems a safe procedure even in the absence of ST in non-severe cases. This could be a practical optionin infants and pre-school children,where ST are painful and difficult to perform.Additional caution should be taken in children with asthma and food allergy.

Use of a fluorescence-based approach to assess short-term responses of the alga Pseudokirchneriella subcapitata to metal stress

This work explores the use of fluorescent probes to evaluate the responses of the green alga Pseudokirchneriella subcapitata to the action of three nominal concentrations of Cd(II), Cr(VI), Cu(II) and Zn(II) for a short time (6 h). The toxic effect of the metals on algal cells was monitored using the fluorochromes SYTOX Green (SG, membrane integrity), fluorescein diacetate (FDA, esterase activity) and rhodamine 123 (Rh123, mitochondrial membrane potential). The impact of metals on chlorophyll a (Chl a) autofluorescence was also evaluated. Esterase activity was the most sensitive parameter. At the concentrations studied, all metals induced the loss of esterase activity. SG could be used to effectively detect the loss of membrane integrity in algal cells exposed to 0.32 or 1.3 μmol L−1 Cu(II). Rh123 revealed a decrease in the mitochondrial membrane potential of algal cells exposed to 0.32 and 1.3 μmol L−1 Cu(II), indicating that mitochondrial activity was compromised. Chl a autofluorescence was also affected by the presence of Cr(VI) and Cu(II), suggesting perturbation of photosynthesis. In conclusion, the fluorescence-based approach was useful for detecting the disturbance of specific cellular characteristics. Fluorescent probes are a useful diagnostic tool for the assessment of the impact of toxicants on specific targets of P. subcapitata algal cells.

Responses of the alga Pseudokirchneriella subcapitata to long-term exposure to metal stress

The green alga Pseudokirchneriella subcapitata has been widely used in ecological risk assessment, usually based on the impact of the toxicants in the alga growth. However, the physiological causes that lead algal growth inhibition are not completely understood. This work aimed to evaluate the biochemical and structural modifications in P. subcapitata after exposure, for 72 h, to three nominal concentrations of Cd(II), Cr(VI), Cu(II) and Zn(II), corresponding approximately to 72 h-EC10 and 72 h-EC50 values and a high concentration (above 72 h-EC90 values). The incubation of algal cells with the highest concentration of Cd(II), Cr(VI) or Cu(II) resulted in a loss of membrane integrity of ~16, 38 and 55%, respectively. For all metals tested, an inhibition of esterase activity, in a dose-dependent manner, was observed. Reduction of chlorophyll a content, decrease of maximum quantum yield of photosystem II and modification of mitochondrial membrane potential was also verified. In conclusion, the exposure of P. subcapitata to metals resulted in a perturbation of the cell physiological status. Principal component analysis revealed that the impairment of esterase activity combined with the reduction of chlorophyll a content were related with the inhibition of growth caused by a prolonged exposure to the heavy metals.