2,048 research outputs found

    Fast algorithm for H.264/AVC intra prediction based on discrete wavelet transform

    Get PDF
    H.264 or MPEG-4 AVC (Advanced Video Coding) is the new world-wide accepted international Standard for video coding, approved by ITU-T and ISO. New Tools have been added to improve the coding efficiency allowing a save up above of 50%, when is compared with previous standards (H.263, MPEG-2 y MPEG-4). From April 2007 there is a new set of profiles known as “all-Intra”. They were born as a sub-set from the “High” profile and have reached a high impact within broadcast industry where the highest quality video formats are demanded. The high efficiency of “all-Intra” mode in H.264 is due to Rate Distortion Optimization (RDO) technique. RDO chooses for each macroblock (MB) the best partition mode and directional prediction. However, the computational burden becomes extremely high due to huge number of prediction-prediction modes that should be evaluated. This article shows a new algorithm for fast partition mode algorithm based on Discrete Wavelet Transform (DWT). It allows reducing the number of candidate modes to those which are strictly defined for each partition. By using the local 2D-DWT over each MB, information of the homogeneity is obtained. It is got from multiresolution analysis of the transformed coefficients in each sub-band. This way it is easier to classify quickly the optimum partition mode avoiding the exhaustive seek made by RDO

    Partial trisomy 13q22-qter associated to leukoencephalopathy and late onset generalised epilepsy

    Get PDF
    The partial trisomy 13q.22 is an uncommon chromosomopathy. We present a case with a partial trisomic component 13q22 and a monosomic component 5p15 from paternal origin. This patient developed early menopause and major neurological disorders as leukoencephalopathy, late onset generalised epilepsy and stroke. She also had fatty acids disturbances and their potential relation to the neurological disorders and early menopause is discussed. The presented case illustrates the phenotype of 13q22-qter in adult age and reaffirms the importance of studying the karyotype of any patient with seizures or leukoencephalopathy particularly when there are associated other clinical features including stroke at a young age, fatty acids disturbances, microcephaly, hypotelorism, short neck, hemangiomata, short fingers or distal swell in thumbs

    Plasmatic level of neurosin predicts outcome of mild cognitive impairment

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Mild Cognitive Impairment (MCI) is a disorder considered to be a transitional stage from health to dementia. Diagnosis of dementias at these early stages is always troublesome because the pathophysiologic events leading to dementia precede clinical symptoms. Thus, the development of biomarkers that can be used to support the diagnosis of dementias at early stages is rapidly becoming a high priority. We have recently reported the value of measuring plasmatic levels of neurosin in the diagnosis of Alzheimer's disease (AD). The aim of this study is to determine whether measuring plasmatic concentration of neurosin is a valuable test to predict progression of MCI.</p> <p>Methods</p> <p>Plasmatic neurosin concentrations were measured in 68 MCI patients and 70 controls subjects. Blood samples were obtained at the beginning of the study. Sixty six patients diagnosed with MCI were observed for 18 months. In 36 patients a second blood sample was obtained at the endpoint.</p> <p>Results</p> <p>The mean value of plasmatic neurosin concentration differs significantly between MCI patients who converted to Dementia with vascular component, those who converted to AD, or those who remained at MCI stage. The relative risk of developing Dementia with vascular component when neurosin levels are higher than 5.25 ng/ml is 13 while the relative risk of developing mild AD when neurosin levels are lower than 5.25 ng/ml is 2. Increases in the levels of neurosin indicate progression to Dementia with vascular component.</p> <p>Conclusion</p> <p>The measurement of plasmatic neurosin level in patients diagnosed with MCI may predict conversion from MCI to Dementia with vascular component. A single measurement is also valuable to estimate the risk of developing AD and Dementia with vascular component. Finally, repeated measurement of plasmatic neurosin might be a useful test to predict outcome in patients with MCI.</p

    Postural control modulation during motor imagery tasks: A systematic review

    Get PDF
    The motor imagery (MI) has two strategies (kinesthetic and visual) and can be defined as an act to codify the mental rehearsal of an intended action, without executing it. Studying the execution of the movement, several researchers believe that the deep muscles of the trunk are activated before the agonist of the limbs, showing a motor neurophysiologic recruitment order.This behavior can be also seen during MI tasks as the postural control, because the postural control is inserted in the movement context. The aim was to investigate, by a systematic review, evidences of MI and the postural control on healthy subjects. The selected articles were searched on different databases, dated from 1985 to 2014.Twelve studies were selected regarding the MI and the postural control on healthy subjects. All articles using balance scale or those which were about clinical conditions were excluded. Data show that kinesthetic MI with high levels of vividness promotes major changes in the body oscillations when comparing with the visual MI. To date, the number of articles about this theme is limited and the results should be interpreted cautiousl

    Rationale and methods of the multicenter randomised trial of a heart failure management programme among geriatric patients (HF-Geriatrics)

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Disease management programmes (DMPs) have been shown to reduce hospital readmissions and mortality in adults with heart failure (HF), but their effectiveness in elderly patients or in those with major comorbidity is unknown. The Multicenter Randomised Trial of a Heart Failure Management Programme among Geriatric Patients (HF-Geriatrics) assesses the effectiveness of a DMP in elderly patients with HF and major comorbidity.</p> <p>Methods/Design</p> <p>Clinical trial in 700 patients aged ≥ 75 years admitted with a primary diagnosis of HF in the acute care unit of eight geriatric services in Spain. Each patient should meet at least one of the following comorbidty criteria: Charlson index ≥ 3, dependence in ≥ 2 activities of daily living, treatment with ≥ 5 drugs, active treatment for ≥ 3 diseases, recent emergency hospitalization, severe visual or hearing loss, cognitive impairment, Parkinson's disease, diabetes mellitus, chronic obstructive pulmonary disease (COPD), anaemia, or constitutional syndrome. Half of the patients will be randomly assigned to a 1-year DMP led by a case manager and the other half to usual care. The DMP consists of an educational programme for patients and caregivers on the management of HF, COPD (knowledge of the disease, smoking cessation, immunizations, use of inhaled medication, recognition of exacerbations), diabetes (knowledge of the disease, symptoms of hyperglycaemia and hypoglycaemia, self-adjustment of insulin, foot care) and depression (knowledge of the disease, diagnosis and treatment). It also includes close monitoring of the symptoms of decompensation and optimisation of treatment compliance. The main outcome variables are quality of life, hospital readmissions, and overall mortality during a 12-month follow-up.</p> <p>Discussion</p> <p>The physiological changes, lower life expectancy, comorbidity and low health literacy associated with aging may influence the effectiveness of DMPs in HF. The HF-Geriatrics study will provide direct evidence on the effect of a DMP in elderly patients with HF and high comorbidty, and will reduce the need to extrapolate the results of clinical trials in adults to elderly patients.</p> <p>Trial registration</p> <p>(ClinicalTrials.gov number, <a href="http://www.clinicaltrials.gov/ct2/show/NCT01076465">NCT01076465</a>).</p

    Genome-wide analyses reveal a potential role for the MAPT, MOBP, and APOE loci in sporadic frontotemporal dementia

    Get PDF
    Frontotemporal dementia (FTD) is the second most common cause of early-onset dementia after Alzheimer disease (AD). Efforts in the field mainly focus on familial forms of disease (fFTDs), while studies of the genetic etiology of sporadic FTD (sFTD) have been less common. In the current work, we analyzed 4,685 sFTD cases and 15,308 controls looking for common genetic determinants for sFTD. We found a cluster of variants at the MAPT (rs199443; p = 2.5 × 10−12, OR = 1.27) and APOE (rs6857; p = 1.31 × 10−12, OR = 1.27) loci and a candidate locus on chromosome 3 (rs1009966; p = 2.41 × 10−8, OR = 1.16) in the intergenic region between RPSA and MOBP, contributing to increased risk for sFTD through effects on expression and/or splicing in brain cortex of functionally relevant in-cis genes at the MAPT and RPSA-MOBP loci. The association with the MAPT (H1c clade) and RPSA-MOBP loci may suggest common genetic pleiotropy across FTD and progressive supranuclear palsy (PSP) (MAPT and RPSA-MOBP loci) and across FTD, AD, Parkinson disease (PD), and cortico-basal degeneration (CBD) (MAPT locus). Our data also suggest population specificity of the risk signals, with MAPT and APOE loci associations mainly driven by Central/Nordic and Mediterranean Europeans, respectively. This study lays the foundations for future work aimed at further characterizing population-specific features of potential FTD-discriminant APOE haplotype(s) and the functional involvement and contribution of the MAPT H1c haplotype and RPSA-MOBP loci to pathogenesis of sporadic forms of FTD in brain cortex

    Clustering COVID-19 ARDS patients through the first days of ICU admission. An analysis of the CIBERESUCICOVID Cohort

    Full text link
    Background Acute respiratory distress syndrome (ARDS) can be classified into sub-phenotypes according to different inflammatory/clinical status. Prognostic enrichment was achieved by grouping patients into hypoinflammatory or hyperinflammatory sub-phenotypes, even though the time of analysis may change the classification according to treatment response or disease evolution. We aimed to evaluate when patients can be clustered in more than 1 group, and how they may change the clustering of patients using data of baseline or day 3, and the prognosis of patients according to their evolution by changing or not the cluster.Methods Multicenter, observational prospective, and retrospective study of patients admitted due to ARDS related to COVID-19 infection in Spain. Patients were grouped according to a clustering mixed-type data algorithm (k-prototypes) using continuous and categorical readily available variables at baseline and day 3.Results Of 6205 patients, 3743 (60%) were included in the study. According to silhouette analysis, patients were grouped in two clusters. At baseline, 1402 (37%) patients were included in cluster 1 and 2341(63%) in cluster 2. On day 3, 1557(42%) patients were included in cluster 1 and 2086 (57%) in cluster 2. The patients included in cluster 2 were older and more frequently hypertensive and had a higher prevalence of shock, organ dysfunction, inflammatory biomarkers, and worst respiratory indexes at both time points. The 90-day mortality was higher in cluster 2 at both clustering processes (43.8% [n = 1025] versus 27.3% [n = 383] at baseline, and 49% [n = 1023] versus 20.6% [n = 321] on day 3). Four hundred and fifty-eight (33%) patients clustered in the first group were clustered in the second group on day 3. In contrast, 638 (27%) patients clustered in the second group were clustered in the first group on day 3.Conclusions During the first days, patients can be clustered into two groups and the process of clustering patients may change as they continue to evolve. This means that despite a vast majority of patients remaining in the same cluster, a minority reaching 33% of patients analyzed may be re-categorized into different clusters based on their progress. Such changes can significantly impact their prognosis
    corecore