Investigating motor imagery tasks by their neural effects - A case study.

Motor imagery, one of the first investigated neural process for Brain-Computer Interfaces (BCIs) still provides a great challenge nowadays. Aiming a better and more accurate control, multiple researches have been conducted by the scientific community. Nevertheless, there is still no robust and confident application developed. In order to augment the potential referring to motor imagery, and to attract user's interest, we propose multiple motor imagery tasks in combination with different visual or auditory stimuli. We use multi-class classification for discrimination and we observe confident classification performance for the task related to user's background.

Recording system and data fusion algorithm for enhancing the estimation of the respiratory rate from photoplethysmogram.

The respiratory rate is a vital parameter that can provide valuable information about the health condition of a patient. The extraction of respiratory information from photoplethysmographic signal (PPG) was actually encouraged by the reported results, our main goal being to obtain accurate respiratory rate estimation from the PPG signal. We developed a fusion algorithm that identifies the best derived respiratory signals, from which is possible to extract the respiratory rate; based on these, a global respiratory rate is computed using the proposed fusion algorithm. The algorithm is qualitatively tested on real PPG signals recorded by an acquisition system we implemented, using a reflection pulse oximeter sensor. Its performance is also statistically evaluated using benchmark dataset publically available from CapnoBase.Org.

Sneddon syndrome: rare disease or under diagnosed clinical entity? Review of the literature related to a clinical case.

Sneddon syndrome is defined by the association of livedo racemosa and recurrent cerebrovascular ischemic lesions. The annual incidence is 4/1,000,000. This syndrome particularly affects young women, some reports suggesting a family predisposition. It is a chronic, progressive, arterio-occlusive disease of unknown etiology that involves small and medium-sized arteries. It is usually associated with antiphospholipid antibodies. We report the case of a female patient with Sneddon syndrome with significant family history, personal history of stroke, epilepsy, migraine, cardiovascular involvement, three miscarriages, cognitive decline, noncompliant to therapy, in the absence of antiphospholipid antibodies. This paper aims to analyze the main characteristic features and management of Sneddon syndrome by conducting a literature review related to a clinical case.

Monitoring the fetal heart rate variations by means of time-variant multivariate analysis.

The analysis of the fetal heart rate (fHR) is important in detecting the fetal distress related with hypoxic episodes, noticed sometimes during the uterine activity, which can severely affect the fetus. Occasional synchrony between the fHR and the maternal heart rate (mHR) was reported and the mHR shows some variations during pregnancy and labor, especially when the contractions are very strong. The current study proposes a new strategy to investigate the relations between the fHR, the mHR and the uterine activity, by applying the time-variant Partial Directed Coherence (tvPDC).

The event synchronous canceller algorithm removes maternal ECG from abdominal signals without affecting the fetal ECG.

Fetal monitoring using abdominally recorded signals (ADS) allows physicians to detect occurring changes in the well-being state of the fetus from the beginning of pregnancy. Mainly based on the fetal electrocardiogram (fECG), it provides the long-term fetal heart rate (fHR) and assessment of the fetal QRS morphology. But the fECG component in ADS is obscured by the maternal ECG (mECG), thus removal of the mECG from ADS improves fECG analysis. This study demonstrates the performance of the event-synchronous interference canceller (ESC) in mECG removal from ADS data, recorded during pregnancy and labor. Its advantage as a compensation method for extended ADS processing is discussed.

Comparison and evaluation of existing methods for the extraction of low amplitude electrocardiographic signals: a possible approach to transabdominal fetal ECG.

Analysis of the fetal ECG (fECG) allows physicians to detect changes in the well-being state of the fetus. But when assessing the fECG through the abdominal signals (ADS), its very low amplitude causes a problem, as the fECG representation in the ADS is buried in a mixture of other signals with stronger energy. Different methods have been proposed in the past to extract the transabdominal fECG for instantaneous fetal heart rate (fHR) computation; four representatives of them are selected for an accurate comparison of their performance in fECG extraction and in fHR estimation. A model for the ADS including all the possible disturbances is developed within this study to generate simulated data as they are required for the quantitative comparison of the algorithms. Their performances and limits considering both the enhancement of the fECG and the ability to preserve fECG morphology are analyzed using the simulated data. The results clearly show that linear methods for maternal ECG removal provide better results with respect to the extraction of the fECG morphology. The algorithms are then tested on real ADS data recorded during labor. Finally, the advantage of considering linear methods for ADS processing is discussed.

Atrial fibrillation in elderly: particularities of management.

Atrial fibrillation (AF), a common and serious cardiac rhythm disturbance, is responsible for substantial morbidity and mortality in the population. Currently about 2.3 million people in the US are diagnosed with AF and, based of the US census, this number is expected to rise to 5.6 million by 2050. It doubles in prevalence with each decade of age, reaching almost 9% at age 80-89 years. It has increased in prevalence over the calendar decades, reaching 'epidemic' proportions. The risk of stroke increases from 1.5% in patients with atrial fibrillation from 50-59 years of age to up to 23.5% for such patients aged 80-89 years. Although the diagnosis of atrial fibrillation is usually straightforward, effective treatment is not. We aimed to discuss how rhythm control of atrial fibrillation can best be achieved in elderly patients, the controversy over the rhythm versus rate control, and prevention of thromboembolism.

Infective endocarditis--a forgotten cause for heart insufficiency in elderly. Case report.

Right heart infective endocarditis in an elderly patient with no previous known risk factors is a very rare situation (even if subacute infective endocarditis has the same chance of occurrence at either a young person, or an elderly patient). We present the case of a 75-years old patient, with no previous cardiac history, addressed to our clinic with nonspecific septic symptoms associated with an edematous syndrome. The patient was treated for right heart valve infective endocarditis; a particularity may be the fact not all Duke criteria were respected. Iatrogeny was involved, our patient having administered a 7-day antibiotic treatment before hospital addressing. The therapeutic probe was positive: excellent evolution under treatment. Few cases of infective endocarditis of the tricuspid valve were reported worldwide, in which the source of infection was unknown in about 80% of cases. In two pediatric cases reported, tricuspid endocarditis was caused by Staphylococcus aureus septicemia following upper respiratory infection. This may also occur in adult cases. Further investigations should be carried out in the future to elucidate the source of infection. Isolated right-sided endocarditis should be included in the differential diagnosis of patients with febrile syndrome, respiratory symptoms and predisposing disease, even when they do not have a pacemaker and are not intravenous-drug users (IVDU).

[Heart insufficiency in elderly--new dimensions of the problem]. / Insuficienta cardiaca la vârstnici dimensiunile problemei.

The 21st century's demographic and epidemiologic perspectives suggest an absolute and percentual increment of elderly population. In the same time the prevalence of heart insufficiency increases with advanced age, which transforms heart failure in a true challenge for health insurance system. This new dimension of the problem resides in the increment of heart insufficiency's prevalence and in the high costs of medical care of these patients. Heart failure's medical costs are high not only due to the necessity of compensating the cardiac function but also due to the necessity of treating the etiology, the risk factors and the co-morbidities with cardiac side effects. Elderly patients usually have a low therapeutic compliance and an important number of iatrogenic reactions mainly due to poly-medication, poly-pathology and cognitive and physical deficiencies, which need special measures of therapeutic education for the patient and family and medical survey, probably best in a nursing house; all these elements increase significantly the cost, which is almost double than the cost for cancer. The prophylaxis in heart insufficiency means an extremely efficient management of entire cardiac pathology in order to delay the moment of heart failure. In elderly patients, the treatment in heart insufficiency is difficult not due to hospital treatment of decompensation episodes but due to low therapeutic compliance at home. We need special programs to ensure medical education of the patient and the family/caregiver in order to avoid iatrogenic pathology and to ensure therapeutic efficiency.

Abdominal fetal ECG enhancement by event synchronous canceller.

Abdominal signals (ADS) recorded from pregnant women represent an important tool for monitoring the fetal heart rate (FHR) variability and the well-being state of the fetus, mainly because it has the advantage of being noninvasive. Thus, no risk is given during recording either for the mother or for the fetus, but complex signal processing steps are necessary, mainly due to the presence of the maternal ECG in the ADS, in order to achieve a clean fetal electrocardiogram (fECG). The paper presents an improved application of the Event Synchronous Canceller (ESC) for maternal electrocardiogram (mECG) suppression. An adaptive mECG template which also includes the P and T waves is considered for the ESC algorithm. ESC is able to perfectly separate the mECG even though the fetal beats overlap with the maternal QRS complex (mQRS). The algorithm is applied both on real ADS recorded during pregnancy and on simulated ADS data; the latter now uses simulation of all signal and noise components, including the fetal and maternal ECG. The modified ESC shows good results in extracting a cleaned fECG signal that can help in reducing the inconsistency in interpretation of FHR. Thus the false positive diagnosis regarding the health status of fetus is strongly reduced.

A Self Organizing Map approach to breast cancer detection.

Detection and characterization of cancer tumors in mammograms is vital in daily clinical practice. The problem of detecting possible cancer areas is very complex due, on one hand, to the diversity in shape of the ill tissue and on the other hand to the poorly defined border between the healthy and the cancerous zone. Even though it has been studied for many years, there are still remaining challenges and directions for future research such as developing better enhancement and segmentation algorithms. The performance of the Self Organizing Map (SOM) in detecting the cancer suspicious regions in digitized mammograms is revealed in this study. In order to achieve the best results we firstly apply the preprocessing algorithms proposed in section II of the study.

[Pulse pressure, arterial compliance and Buckberg index in hypertensive patients treated with nebivolol and nitrates]. / Presiunea pulsului, complianta arterelor de conductanta si irigatia subendocardica la hipertensivii tratati cu nebivolol si nitrati.

OBJECTIVE: To evaluate the effect of nebivolol and nitrate administration on the arterial compliance--an essential factor for left ventricular hypertrophy regression. MATERIAL AND METHOD: The arterial compliance was assessed in 32 hypertensive patients (mean age 52.3 years +/- 11, M/F ratio = 26/6) before drug administration, three hour post oral intake of nebivolol 5 mg and five minutes after sublingual 0.5 mg nitroglycerin. PARAMETERS: mean aortic blood pressure (PAom), pulse pressure (PP), augmentation index (AGIx) and Buckberg index (diastolic pressure-time index/systolic pressure-time index). The statistical significance of the results was determined by means of t-Student test. RESULTS: After nebivolol: PAom decreased from 131.2 +/- 15 mmHg to 118 +/- 15.3 mmHg; PP decreased from 72.5 +/- 12 mmHg to 52.3 +/- 11.3 mmHg; AG decreased from 17 to 10.2 mmHg, AGIx decreased from 26.4% to 22.3%, Buckberg index increased from 145.4 +/- 25% to 161.4 +/- 30%. After nitroglycerin: PAom decreased to 108.5 +/- 12 mmHg; PP decreased to 41.2 +/- 9.3 mmHg; AG decreased to 2.3 mmHg, AGIx decreased to 3.6%, Buckberg index increased to 171.2 +/- 32%. CONCLUSIONS: Nebivolol and nitrates determined a significant lowering of mean aortic pressure and an increase of the arterial compliance suggesting a beneficial effect that could promote the regression of left ventricular hypertrophy.

[Iatrogenic disease in elderly. Case report]. / Iatrogenia la vârstnic. Caz clinic.

Longer life expectancy and modern diagnostic and therapeutic advances favoured the ever more frequent development of ischaemic nephropathy (IN) characterized by the presence of atherosclerotic stenosis in both renal arteries (ARAS); 7% of patients older than 65 years with cardiovascular risk factors have ARAS but the prevalence grows to 20% in patients with coronary artery disease, to 42% in patients with aorto-iliac disease and to 67.5% in patients with peripheral artery atherosclerotic disease. Moreover the patient is later diagnosed with IN until de-hydratation or treatment with angiotensin converting enzyme inhibitors or angiotensin-2-receptor inhibitors. This therapy may present a hazard for elderly patients with unsuspected atherosclerotic renovascular disease; the risk may grow if nonsteroidal anti-inflammatory drugs are associated. Long life expectancy, associated comorbidities, multi-medication and functional failures induce a high risk for iatrogenic disease in elderly.

Abdominal signals: denoising by application of the event synchronuous canceller.

The electrical activity recorded on the abdomen during pregnancy and labor (abdominal signals, ADS) contains vital information about the health state of both mother and fetus. The most important signal related with the health of fetus, extensively studied by now, is the fetal ECG (fECG) which allows physicians to examine the evolution of the fetus and to identify possible heart diseases of fetus. The movement of the fetus which shows up in the electrohysterogram (EHG), extracted from ADS, indicates a normal pregnancy. This paper presents a method of removing the maternal ECG (mECG) from ADS in order extract the EHG and to obtain information about the uterine contractions and fetal movements. After removing the mECG and the fECG, the ADS, filtered in the frequency range of the uterine activity, is further used to predict labor or preterm labor. The ADS, cleaned from the mECG allows also the analysis of the fECG for fetal monitoring.

[Iatrogeny and the elderly]. / Iatrogenia si vârstnicii.

Discussions about the impact of iatrogeny over general health were avoided and neglected for a very long time. It was brought to medical interest due to recent studies concerning therapeutic compliance, patient's medical education and acute awareness of ethical implications of medical activities. Even if iatrogeny was always present in medicine, we realized but recently the dimensions and the necessity of a coherent and systematic approach of this problem. Iatrogenic pathology in elderly population has even a bigger impact due to conjugation of two major demographic phenomena: an absolute and percentage increase of elderly population parallel with an increase of prevalence of iatrogenic pathology with age. That's why iatrogeny in elderly becomes a major health problem, unfortunately often ignored, neglected and even obscured inspite of well-recognized impact over duration and quality of patient's life as well as over the cost of medical assistance.

[Descriptive epidemiologic study of nosocomial infections in "C.I. Parhon" hospital of Iasi]. / Studiu epidemiologic descriptiv privind infectiile nosocomiale in spitalul "Dr. C.I. Parhon" Iasi.

Nosocomial infections (NI) represent a major public health problem. The descriptive study was carried out during one year, based on a lot of 12,731 in-patients from "C.I. Parhon" hospital. The objectives of the study were assessment of NI incidence and risk factors as well as monitoring resistance to antimicrobial drugs of bacterial pathogens from the hospital. The results of the study show lower NI incidence rates: 0.27%, most of them (91.5%) being urinary tract infections in the age group 65 y and over. 42.8% of cases were associated with risk factor of diabetes mellitus, neoplasm, skin or cardiovascular chronic conditions. The main etiological agent found for the NI was pseudomonas pyocyanea resistant to antibiotics. The antibiotic sensitivity analysis for the other gram negative rods illustrates gradually acquired resistance to the third or fourth generation of cephalosporins.

[Treatment with hydroxymethylglutaryl coenzyme-A-reductase inhibitors in elderly patients: is it necessary?]. / Tratamentul cu inhibitori ai hidroxi-metil-glutaril coenzima-A-reductazei: o necesitate in tratamentul dislipidemiei la vârstnic?

OBJECTIVE: To study the benefit of the therapy with hydroxymethylglutaryl coenzyme A reductase inhibitors (simvastatin) associated with diet in treating dyslipidemia in elderly patients, considering that they are more exposed to sudden death, myocardial infarction and stroke. Efficient and long-term serum cholesterol concentration lowering has beneficial effects on the risk for coronary heart disease as well as on other major cardiovascular risk factors such as hypertension and diabetes. METHODS: A retrospective study of 84 patients aged > or = 65 years, admitted in the last 6 months in Medical Clinic IV, was conducted. Admission criteria in the study were: age > or = 65 years old and high serum levels of cholesterol, triglycerides and LDL-C/HDL-C ratio. The patient population was divided into two groups: Group I of 40 patients treated for dyslipidemia only with diet and Group II with 44 patients in which was associated treatment with hydroxymethylglutaryl coenzyme A reductase inhibitors, 10 mg/day. The patients were controlled when admitted in the study and then at 3 and 6 weeks afterwards. RESULTS: Serum cholesterol and triglycerides concentration lowering was modest in Group I at 3 and 6 weeks, maybe because we registered a progressively lowered compliance of patients to hypocholesterolemic diet. In Group II the results were much better as we obtained significant serum cholesterol and triglycerides levels lowering after 3 weeks of treatment, and in 32 cases (72%) we had a normal lipid profile after 6 weeks of treatment. The other 12 patients (28%) abandoned treatment after 4 weeks of therapy because of financial reasons. There were no side effects during the treatment with hydroxymethylglutaryl coenzyme A reductase inhibitors. CONCLUSIONS: The therapy with hydroxymethylglutaryl coenzyme A reductase inhibitors associated to hypocholesterolemic diet controlled efficiently dyslipidemia in elderly patients. Diet alone could not control cholesterol and triglycerides levels, mainly because of lack of adherence of the patients to the diet. Based on the fact that dyslipidemia is a major, independent cardiovascular risk factor, we consider that therapy with hydroxymethylglutaryl coenzyme-A-reductase inhibitors is beneficial in elderly patients because of their efficacity, minimal side effects and protection against sudden death, myocardial infarction and stroke.

[Relation between arterial compliance and the prematurity of reflected wave on pulse pressure curve evaluated by tonometric sphygmography]. / Relatia dintre complianta arteriala si precocitatea undei reflectate la nivelul curbei presiunii pulsului evaluata prin sfigmografia tonometrica.

The effect of antihypertensive drugs on the arterial pressure pulse can usually be explained by a change in the timing or intensity of wave reflection or by alteration in the pattern of ventricular ejection. Alteration in timing wave reflection is believed to cause the characteristic changes of pressure wave such: augmentation, augmentation index, "precocity index of second systolic peek" (P2). After calcium channel blockers augmentation decreases from 15 mmHg to 9.4 mmHg, augmentation index P2/P1 (P1 is the first systolic peek) decreases from 132.2 +/- 20% to 129.2 +/- 19.5% and "precocity index of P2" increases from 68.8 +/- 5% ejection duration to 71.8 +/- 4.6% ejection duration.

[Oxidative stress in atherosclerosis]. / Stresul oxidativ în ateroscleroza.

Oxidative stress is the result of the imbalance between pro-oxidant and antioxidant factors. The participation of oxidative stress in atherosclerosis (ATS) is reflected by lipid peroxidation which is a process initiated and maintained by oxygen reactive species generated by the aterogenic cells themselves. The endothelial aggression in ATS is accompanied by endothelial dysfunction, which is due to the neutralization of nitric oxide by superoxid anion. The key role in the onset and the development of the ATS lesions belongs to oxidated LDL-cholesterol that influence at different levels and by several mechanisms the ATS process. The neutralization of the toxic effects of free radicals is due to the endo and exogen antioxidant systems. It appears that the individual antioxidant status is influenced by environmental factors as well as by a genetic determinant. The antioxidant therapy, which is controversial at the moment, represents an associated therapy in endothelial dysfunction from ATS.