Relations between cognition and motricity in children with neonatal arterial ischemic stroke

Introduction and goalPerinatal arterial ischemic stroke (PAIS) affects one child for 4000 births. The few studies about cognitive development specific to PAIS showed that cognitive performances in this population do not follow up a normal development (Westmacott et al., 2010; Ricci et al., 2008). Based on new data about relation between motricity and cognition (Smits-Engelsman et Hill, 2012), and on the theory of the embodied cognition, led us to hypothesize that cognitive performances would be correlated to the motor performances in children with PAIS.Patients and methodologyWe tested 77 7 years old children meeting the criteria of neonatal AIS, with a diagnosis before the 28th day of life relying on cerebral imagery. After excluding children with seizure and bi-hemispheric lesion, 56 children participated to our study. The cognitive evaluation was performed with the Wechsler Intelligence Scale for Children (WISC-4), the motor evaluation relied on testing of gross motor of the upper arm (Box and Block Test) and fine prehension test (“Nine Hole Peg Test”). The localisation of the lesion, the economic level of parents, the gender, sensory impairments and the presence of hemiplegia were collected. We analyzed these results with simple linear regression.ResultsThe main result of our study is the significative correlation (P<0.03) between scores of the WISC4 (except for working memory index) and motor results. In contrast we did not find any correlation between the scores of the WISC4 and the presence of hemiplegia or with lesion localization.DiscussionMany brain networks develop during the first year through sensorimotor experiences, which contribute to the emergence of knowledge. This concept of development, supported by the approach embodied cognition, can explain the correlations between cognition and motor found in our work and in several studies with children with other early neurological damage

Pediatric stroke related to Lyme neuroborreliosis: Data from the Swiss NeuroPaediatric Stroke Registry and literature review.

Cerebrovascular complications of Lyme neuroborreliosis (LNB) are poorly documented in the paediatric population. We performed a retrospective analysis from prospectively registered cases of acute ischemic stroke (AIS) from the Swiss NeuroPaediatric Stroke Registry (SNPSR) from 2000 to 2015. Only cases with serologically confirmed LNB were included. In addition, a literature review on paediatric stroke cases secondary to Lyme neuroborreliosis in the same time frame was performed. 4 children out of 229 children with arterial ischemic childhood stroke and serologically confirmed LNB were identified in the SNPSR giving a global incidence of 1.7%. Median age was 9.9 years. A prior history of tick bites or erythema migrans (EM) was reported in two cases. Clinical presenting signs were suggestive of acute cerebellar/brainstem dysfunction. On imaging, three children demonstrated a stroke in the distribution of the posterior inferior cerebellar artery. The remaining fourth child had a "stroke-like" picture with scattered white matter lesions and a multifocal vasculitis with prominent basilar artery involvement. Lymphocytic pleocytosis as well as intrathecal synthesis of Borrelia burgdorferi antibodies were typical biological features. Acute intravenous third generation cephalosporins proved to be effective with rapid improvement in all patients. No child had recurrent stroke. Data from the literature concerning eight patients gave similar results, with prominent posterior circulation stroke, multifocal vasculitis and abnormal CSF as distinctive features. Lyme Neuroborreliosis accounts for a small proportion of paediatric stroke even in an endemic country. The strong predilection towards posterior cerebral circulation with clinical occurrence of brainstem signs associated with meningeal symptoms and CSF lymphocytosis are suggestive features that should rapidly point to the diagnosis. This can be confirmed by appropriate serological testing in the serum and CSF. Clinicians must be aware of this rare neurological complication of Lyme disease that demands specific antibiotic treatment

Muon spin rotation measurements of the superfluid density in fresh and aged superconducting PuCoGa5_5

We have measured the temperature dependence and magnitude of the superfluid density $\rho_{\rm s}(T)$ via the magnetic field penetration depth $\lambda(T)$ in PuCoGa$_5$ (nominal critical temperature $T_{c0} = 18.5$ K) using the muon spin rotation technique in order to investigate the symmetry of the order parameter, and to study the effects of aging on the superconducting properties of a radioactive material. The same single crystals were measured after 25 days ($T_c = 18.25$ K) and 400 days ($T_c = 15.0$ K) of aging at room temperature. The temperature dependence of the superfluid density is well described in both materials by a model using d-wave gap symmetry. The magnitude of the muon spin relaxation rate $\sigma$ in the aged sample, $\sigma\propto 1/\lambda^2\propto\rho_s/m^*$, where $m^*$ is the effective mass, is reduced by about 70% compared to fresh sample. This indicates that the scattering from self-irradiation induced defects is not in the limit of the conventional Abrikosov-Gor'kov pair-breaking theory, but rather in the limit of short coherence length (about 2 nm in PuCoGa$_5$) superconductivity.Comment: 11 page

Manual dexterity, but not cerebral palsy, predicts cognitive functioning after neonatal stroke

AIM: To disentangle the respective impacts of manual dexterity and cerebral palsy (CP) in cognitive functioning after neonatal arterial ischaemic stroke. METHOD: The population included 60 children (21 females, 39 males) with neonatal arterial ischaemic stroke but not epilepsy. The presence of CP was assessed clinically at the age of 7 years and 2 months (range 6y 11mo-7y 8mo) using the definition of the Surveillance of CP in Europe network. Standardized tests (Nine-Hole Peg Test and Box and Blocks Test) were used to quantify manual (finger and hand respectively) dexterity. General cognitive functioning was evaluated with the Wechsler Intelligence Scale for Children, Fourth Edition. Simple and multiple linear regression models were performed while controlling for socio-economic status, lesion side, and sex. RESULTS: Fifteen children were diagnosed with CP. In simple regression models, both manual dexterity and CP were associated with cognitive functioning (β=0.41 [p=0.002] and β=0.31 [p=0.019] respectively). However, in multiple regression models, manual dexterity was the only associated variable of cognitive functioning, whether or not a child had CP (β=0.35; p=0.007). This result was reproduced in models with other covariables (β=0.31; p=0.017). INTERPRETATION: As observed in typically developing children, manual dexterity is related to cognitive functioning in children having suffered a focal brain insult during the neonatal period. WHAT THIS PAPER ADDS: Manual dexterity predicts cognitive functioning after neonatal arterial ischaemic stroke. Correlations between manual dexterity and cognitive functioning occur irrespective of sex, lesion side, presence of cerebral palsy, and socio-economic status. Residual motor ability may support cognitive functioning

Evolving microstructure: Mechanisms of electromigration in stressed aluminum-copper and copper films

We report on a collective body of work wherein we have studied the mass transport phenomena which are likely to be operative during stress driven changes in microstructure arising from electromigration and stress voiding. Our goal is to understand such microstructural evolution leading to failure of the metal lines or interconnects associated with integrated electronic circuits or chips. This work, when complete, will lead to improved electronics performance and reliability and faster product development arising from accurate and predictive models of wearout phenomena. We report on the role of thermal induced strain leading to hole and hillock formation, the influence of grains structure on the reliability of Al- based interconnects, and the observation of counter-current electromigration of Ua in Al grain boundaries

Hip fracture risk assessment: Artificial neural network outperforms conditional logistic regression in an age- and sex-matched case control study

Copyright @ 2013 Tseng et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Background - Osteoporotic hip fractures with a significant morbidity and excess mortality among the elderly have imposed huge health and economic burdens on societies worldwide. In this age- and sex-matched case control study, we examined the risk factors of hip fractures and assessed the fracture risk by conditional logistic regression (CLR) and ensemble artificial neural network (ANN). The performances of these two classifiers were compared. Methods - The study population consisted of 217 pairs (149 women and 68 men) of fractures and controls with an age older than 60 years. All the participants were interviewed with the same standardized questionnaire including questions on 66 risk factors in 12 categories. Univariate CLR analysis was initially conducted to examine the unadjusted odds ratio of all potential risk factors. The significant risk factors were then tested by multivariate analyses. For fracture risk assessment, the participants were randomly divided into modeling and testing datasets for 10-fold cross validation analyses. The predicting models built by CLR and ANN in modeling datasets were applied to testing datasets for generalization study. The performances, including discrimination and calibration, were compared with non-parametric Wilcoxon tests. Results - In univariate CLR analyses, 16 variables achieved significant level, and six of them remained significant in multivariate analyses, including low T score, low BMI, low MMSE score, milk intake, walking difficulty, and significant fall at home. For discrimination, ANN outperformed CLR in both 16- and 6-variable analyses in modeling and testing datasets (p?<?0.005). For calibration, ANN outperformed CLR only in 16-variable analyses in modeling and testing datasets (p?=?0.013 and 0.047, respectively). Conclusions - The risk factors of hip fracture are more personal than environmental. With adequate model construction, ANN may outperform CLR in both discrimination and calibration. ANN seems to have not been developed to its full potential and efforts should be made to improve its performance.National Health Research Institutes in Taiwa

Cohort profile: the Swiss Cerebral Palsy Registry (Swiss-CP-Reg) cohort study.

BACKGROUND Cerebral Palsy (CP) is a group of permanent disorders of movement and posture that follow injuries to the developing brain. It results in motor dysfunction and a wide variety of comorbidities like epilepsy; pain; speech, hearing and vision disorders; cognitive dysfunction; and eating and digestive difficulties. Central data collection is essential to the study of the epidemiology, clinical presentations, care, and quality of life of patients affected by CP. CP specialists founded the Swiss Cerebral Palsy Registry (Swiss-CP-Reg) in 2017. This paper describes the design, structure, aims and achievements of Swiss-CP-Reg and presents its first results. METHODS Swiss-CP-Reg records patients of any age diagnosed with CP who are born, are treated, or live in Switzerland. It collects data from medical records and reports, from questionnaires answered by patients and their families, and from data linkage with routine statistics and other registries. The registry contains information on diagnosis, clinical presentation, comorbidities, therapies, personal information, family history, and quality of life. RESULTS From August 2017 to August 2021, 546 participants (55% male, mean age at registration 8 years [interquartile range IQR: 5-12]), were enrolled in Swiss-CP-Reg. Most had been born at term (56%), were less than two years old at diagnosis (73%, median 18 months, IQR: 9-25), and were diagnosed with spastic CP (76%). Most (59%) live with a mild motor impairment (Gross Motor Function Classification System [GMFCS] level I or II), 12% with a moderate motor impairment (GMFCS level III), and 29% with a severe motor impairment (GMFCS level IV or V). In a subset of 170 participants, we measured intelligence quotient (IQ) and saw lower IQs with increasing GMFCS level. Swiss-CP-Reg has a strong interest in research, with four nested projects running currently, and many more planned. CONCLUSIONS Swiss-CP-Reg collects and exchanges national data on people living with CP to answer clinically relevant questions. Its structure enables retrospective and prospective data collection and knowledge exchange between experts to optimise and standardise treatment and to improve the health and quality of life of those diagnosed with CP in Switzerland

A note on Youden's J and its cost ratio

<p>Abstract</p> <p>Background</p> <p>The Youden index, the sum of sensitivity and specificity minus one, is an index used for setting optimal thresholds on medical tests.</p> <p>Discussion</p> <p>When using this index, one implicitly uses decision theory with a ratio of misclassification costs which is equal to one minus the prevalence proportion of the disease. It is doubtful whether this cost ratio truly represents the decision maker's preferences. Moreover, in populations with a different prevalence, a selected threshold is optimal with reference to a different cost ratio.</p> <p>Summary</p> <p>The Youden index is not a truly optimal decision rule for setting thresholds because its cost ratio varies with prevalence. Researchers should look into their cost ratio and employ it in a decision theoretic framework to obtain genuinely optimal thresholds.</p