99 research outputs found

    Brain preservation with selective cerebral perfusion, moderate hypothermia and low flow rate

    Get PDF
    BackgroundHypothermic circulatory arrest (HCA) is employed for aortic arch and other complex operations, often with selective cerebral perfusion (SCP). Our previous work has demonstrated real-time evidence of improved brain protection using SCP at 18°C. The purpose of this study was to evaluate the utility of SCP at warmer temperatures (25°C) and its impact on operating times.MethodsFrom 2000 to 2010, 116 patients diagnosed IAA, 40 IAA with VSD, 31 single ventricle, 19 Coa with VSD, 17 DORV, 6 TGA and 3 CAVD underwent total repair using SCP 25–23 hypothermia with low flow rate for 20–35min. Circulatory arrest (CA), cross clamp (Cx), CPB and post-op complications are retrospectively analyzed.ResultsThe mean age 12–35days, weight 1.9–4.0. The complexity of the disease was determinant in the CPB and CX time, the lowest temperature was 19 in very selected patients, the average temp. was 23°C. CA was in 18 (6.4%). 27% delay sterna closure. Wound infection 11% and 8% mortality.ConclusionOur study supports the conclusion that systemic circulatory arrest with selective cerebral perfusion at 25°C can be safely performed while providing comparable cerebral and end-organ protection to that of 18°C with SCP. In addition, the employment of a more tepid temperature allows for significantly shorter operative times, which may clinically translate into improved outcomes for children undergoing surgical repair of complex congenital heart defects

    Verification and Codesign of the Package and Die Power Delivery System Using Wavelets

    Full text link

    Evaluating the Contributions of State of the Art Assessment Techniques to Predicting Memory Outcome after Unilateral Anterior Temporal Lobectomy

    Get PDF
    Purpose:Although anterior temporal lobectomy (ATL) is an effective treatment for many patients with medically refractory temporal lobe epilepsy (TLE), one risk associated with this procedure is postsurgical decline in memory. A substantial number of past studies examined factors that predict memory decline after surgery, but few have investigated multiple predictors simultaneously or considered measures that are currently in use. Methods: This study compared the relative contributions made by presurgical neuropsychological test scores, MRI-based hippocampal volumetric analysis, and Wada test results to predicting memory outcome after ATL in a group of 87 patients. Results: Logistic regression analyses indicated that noninvasive procedures (neuropsychological testing and MRI) made significant contributions to improving the prediction of memory outcome in this sample. The results from the Wada procedure did not significantly improve prediction once these other factors were considered. The only exception was in predicting memory for visual information after a delay, in which Wada results improved prediction accuracy from 78% to 81%. Conclusions: Current neuropsychological tests and MRI volumetric measures predict changes in verbal and visual memory after ATL. The relatively small change in correct classification rates when Wada memory scores are considered calls into question the benefits of using Wada test results to predict memory outcome when the results of noninvasive procedures are available

    Implementation of improved Levenshtein algorithm for spelling correction word candidate list generation

    Get PDF
    Candidates’ list generation in spelling correction is a process of finding words from a lexicon that are close to the incorrect word. The most widely used algorithm to generate the candidate list is the Levenshtein algorithm. However, the algorithm consumes high computational cost, especially when there is a large number of spelling errors. The reason is that calculating Levenshtein algorithm includes operations that create an array and fill the cells of this array by comparing the characters of an incorrect word with the characters of a word from a lexicon. Since most lexicons contain millions of words, such operations will be repeated millions of times for each incorrect word in order to generate its candidates’ list. This study proposes an improved Levenshtein algorithm that reduces the operation steps in comparing characters between the query and lexicon words. Experimental results show that the proposed algorithm outperformed the Levenshtein algorithm in terms of processing time by having 32.43% percentage decrease

    Polygenic risk heterogeneity among focal epilepsies

    Get PDF
    Focal epilepsy (FE) is clinically highly heterogeneous. It has been shown recently that not only rare but also a subset of common genetic variants confer risk for FE. The relatively modest power of genetic studies in FE suggests a high genetic heterogeneity of FE when grouped as one disorder. We hypothesize that the clinical heterogeneity of FE is correlated with genetic heterogeneity on a common risk variant level. To test the hypothesis, we used an FE polygenic risk score "FE-PRS" that combines small effect sizes of thousands of common variants from the largest FE-GWAS (genome-wide association study) into a single measure. We grouped 414 individuals with FE according to common clinical features into subgroups, either by one feature at a time or by all features combined in a cluster analysis. We examined their association with FE-PRS compared to 20 435 matched population controls and observed heterogeneous FE-PRS burden among the subgroups. The highest phenotypic variance explained by FE-PRS was identified in a cluster analysis-defined FE subgroup where all individuals had unknown etiologies and psychiatric comorbidities, and the majority had early onset seizures. Our results indicate that genetic factors associated with FE have differential burden among FE subtypes. Future studies using better-powered FE-PRS might have clinical utility.Peer reviewe

    APOE ɛ4 is associated with postictal confusion in patients with medically refractory temporal lobe epilepsy

    Get PDF
    This study examined the relationship between the APOE ɛ4 allele and postictal confusion in patients with medically intractable temporal lobe epilepsy (TLE). Patients with at least one ɛ4 allele (n = 22) were three times more likely to exhibit postictal confusion (68%) than the 63 patients without ɛ4 (43%). These preliminary results demonstrate that APOE ɛ4 is associated with an increased risk of postictal confusion in patients with medically intractable TLE, suggesting possible dysfunction in neuronal recovery mechanisms

    Is Mossy Fiber Sprouting a Potential Therapeutic Target for Epilepsy?

    Get PDF
    Mesial temporal lobe epilepsy (MTLE) caused by hippocampal sclerosis is one of the most frequent focal epilepsies in adults. It is characterized by focal seizures that begin in the hippocampus, sometimes spread to the insulo-perisylvian regions and may progress to secondary generalized seizures. Morphological alterations in hippocampal sclerosis are well defined. Among them, hippocampal sclerosis is characterized by prominent cell loss in the hilus and CA1, and abnormal mossy fiber sprouting (granular cell axons) into the dentate gyrus inner molecular layer. In this review, we highlight the role of mossy fiber sprouting in seizure generation and hippocampal excitability and discuss the response of alternative treatment strategies in terms of MFS and spontaneous recurrent seizures in models of TLE (temporal lobe epilepsy)

    Neurological disorder-associated genetic variants in individuals with psychogenic nonepileptic seizures

    Get PDF
    Psychogenic nonepileptic seizures (PNES) are diagnosed in approximately 30% of patients referred to tertiary care epilepsy centers. Little is known about the molecular pathology of PNES, much less about possible underlying genetic factors. We generated whole-exome sequencing and whole-genome genotyping data to identify rare, pathogenic (P) or likely pathogenic (LP) variants in 102 individuals with PNES and 448 individuals with focal (FE) or generalized (GE) epilepsy. Variants were classified for all individuals based on the ACMG-AMP 2015 guidelines. For research purposes only, we considered genes associated with neurological or psychiatric disorders as candidate genes for PNES. We observe in this first genetic investigation of PNES that six (5.88%) individuals with PNES without coexistent epilepsy carry P/LP variants (deletions at 10q11.22-q11.23, 10q23.1-q23.2, distal 16p11.2, and 17p13.3, and nonsynonymous variants in NSD1 and GABRA5). Notably, the burden of P/LP variants among the individuals with PNES was similar and not significantly different to the burden observed in the individuals with FE (3.05%) or GE (1.82%) (PNES vs. FE vs. GE (3x2 chi (2)), P=0.30; PNES vs. epilepsy (2x2 chi (2)), P=0.14). The presence of variants in genes associated with monogenic forms of neurological and psychiatric disorders in individuals with PNES shows that genetic factors are likely to play a role in PNES or its comorbidities in a subset of individuals. Future large-scale genetic research studies are needed to further corroborate these interesting findings in PNES.Peer reviewe

    Healthcare Utilization and Clinical Characteristics of Genetic Epilepsy in Electronic Health Records

    Get PDF
    Understanding the clinical characteristics and medical treatment of individuals affected by genetic epilepsies is instrumental in guiding selection for genetic testing, defining the phenotype range of these rare disorders, optimizing patient care pathways and pinpointing unaddressed medical need by quantifying healthcare resource utilization. To date, a matched longitudinal cohort study encompassing the entire spectrum of clinical characteristics and medical treatment from childhood through adolescence has not been performed. We identified individuals with genetic and non-genetic epilepsies and onset at ages 0–5 years by linkage across the Cleveland Clinic Health System. We used natural language processing to extract medical terms and procedures from longitudinal electronic health records and tested for cross-sectional and temporal associations with genetic epilepsy. We implemented a two-stage design: in the discovery cohort, individuals were stratified as being ‘likely genetic’ or ‘non-genetic’ by a natural language processing algorithm, and controls did not receive genetic testing. The validation cohort consisted of cases with genetic epilepsy confirmed by manual chart review and an independent set of controls who received negative genetic testing. The discovery and validation cohorts consisted of 503 and 344 individuals with genetic epilepsy and matched controls, respectively. The median age at the first encounter was 0.1 years and 7.9 years at the last encounter, and the mean duration of follow-up was 8.2 years. We extracted 188,295 Unified Medical Language System annotations for statistical analysis across 9659 encounters. Individuals with genetic epilepsy received an earlier epilepsy diagnosis and had more frequent and complex encounters with the healthcare system. Notably, the highest enrichment of encounters compared with the non-genetic groups was found during the transition from paediatric to adult care. Our computational approach could validate established comorbidities of genetic epilepsies, such as behavioural abnormality and intellectual disability. We also revealed novel associations for genitourinary abnormalities (odds ratio 1.91, 95% confidence interval: 1.66–2.20, P = 6.16 × 10−19) linked to a spectrum of underrecognized epilepsy-associated genetic disorders. This case-control study leveraged real-world data to identify novel features associated with the likelihood of a genetic aetiology and quantified the healthcare utilization of genetic epilepsies compared with matched controls. Our results strongly recommend early genetic testing to stratify individuals into specialized care paths, thus improving the clinical management of people with genetic epilepsies
    • …
    corecore