1,720,971 research outputs found

    Age- and sex-related reference ranges of alanine aminotransferase levels in children: European paediatric HCV network.

    No full text
    BACKGROUND: Serum alanine aminotransferase (ALT) levels are commonly used to indicate liver damage. Although elevated levels indicate possible liver injury, abnormalities, or disease, some patients with "normal" ALT levels have minimal to mild liver disease. Recently, ALT reference ranges for adults were queried and revised ranges proposed with lower upper limits of normality. The appropriateness of current paediatric ALT reference ranges is unclear. MATERIAL AND METHODS: Hepatitis C virus (HCV)-uninfected children from the European Paediatric HCV Network represent a large population of healthy children born to HCV-infected mothers, with ALT observations collected prospectively from birth. Linear regression identified factors associated with ALT levels while accounting for within-child repeated measurements. ALT centiles stratified by sex were calculated using maximum penalized likelihood methods and LMS software. RESULTS: A total of 1293 HCV-uninfected children had 5011 ALT measurements during follow-up. ALT levels significantly decreased with increasing age, whilst ALT levels were significantly lower in girls than boys. Reference cutoffs representing the 95th centiles before 18 months of age were 60 U/L for boys and 55 U/L for girls, decreasing to 40 U/L for boys and 35 U/L for girls after 18 months of age. CONCLUSIONS: These reference ranges represent a unique investigation of ALT levels in a healthy child population. We show lower and more detailed age-related cutoffs of normality than available. Additionally, we demonstrate a significant effect of sex on ALT reference ranges, which has not previously been described in children younger than 5 years of age

    Excluding hepatitis C virus (HCV) infection by serology in young infants of HCV infected mothers

    No full text
    Aim: To identify the age at which HCV infection can be accurately excluded by serology in young children born to HCV-infected mothers and to determine an appropriate schedule of antibody testing, most informative to clinical practice. Methods: Children born to HCV-infected mothers were followed in centres of the European Paediatric HCV Network. Turnbull survival analysis techniques were used to estimate the age at which HCV-uninfected children will lose maternally acquired HCV antibodies. Factors associated with age at antibody loss were assessed in logistic regression. Results: In 1104 children followed from birth and later confirmed to be HCV uninfected, an estimated 57% will have lost passively acquired HCV antibodies before 6 mo of age and an estimated 95% by 12 mo. Maternal HCV viraemia antenatally was associated with later,. and maternal HIV-HCV co-infection with earlier loss of antibody. Actual antibody testing of uninfected children at 12 mo identified 82% of those tested to be anti-HCV negative. Conclusions: Serological confirmation of HCV uninfection remains necessary given the uncertainty in the specificity of virological tests. These results suggest that, in most children, HCV infection can be ruled out with serological testing at an earlier age than previously thought, and that nearly all children born to HCV-infected mothers will have lost passively acquired maternal antibodies by 1 y of age. Antibody loss was significantly later among children born to HCV viraemic mothers. The earlier loss of HCV antibodies in children born to HIV co-infected mothers may be due to HIV treatment

    Growth in the first 5 years of life is unaffected in children with perinatally-acquired hepatitis C infection

    No full text
    Objectives To identify the effect of vertical hepatitis C virus (HCV) infection or exposure on growth in childhood. Study design Children (n = 1203) born to HCV-infected mothers were followed up from birth prospectively in centers of the European Paediatric Hepatitis C virus Network. Z-scores compared height- and weight-for-age in HCV-infected and -uninfected children, adjusting for other factors using linear regression. We also quantified the effect of maternal chronic infection with HCV on childhood growth. Results There was no significant effect of vertical HCV infection on growth (height P =.223, weight P =.095) nor a significant effect of maternal chronic infection with HCV (height P =.733, weight P =.274). Prematurity and maternal injecting drug use were associated with a significant reduction in height (P <.001) and weight (P <.001) in all HCV-exposed children. Conclusions This population of HCV exposed infants has higher rates of maternal injecting drug use and prematurity than standard populations and so there are implications for growth of these children, but this is not a direct result of HCV infection or exposure to chronic maternal HCV infection

    The management of HCV infected pregnant women and their children European paediatric HCV network

    No full text
    Background/Aims: As evidence accumulates relating to mother-to-child (vertical) transmission of hepatitis C virus (HCV), it is timely to draw up guidelines for the clinical management of HCV infected pregnant women and their children. Methods: A review of evidence from the European Paediatric HCV Network (EPHN) prospective study of HCV infected women and their children and other published studies. Meeting of EPHN clinical experts to reach a consensus on recommendations for management. Each recommendation was graded according to the level of evidence. Results/conclusions: Although several risk factors for mother-to-child transmission have been identified, none are modifiable and there are currently no interventions available to prevent vertical transmission of HCV. Data on timing of loss of maternal antibodies and reliability of diagnostic tests inform the optimum follow-up schedule for confirmation or exclusion of infection in children born to HCV infected women. Based on the current evidence, routine antenatal screening for HCV should not be introduced and neither elective caesarean section nor avoidance of breastfeeding should be recommended to HCV infected women to prevent mother-to-child transmission of HCV. HCV/HIV co-infected women should follow existing HIV guidelines. © 2005 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved

    The management of HCV infected pregnant women and their children European paediatric HCV network

    No full text
    BACKGROUND/AIMS: As evidence accumulates relating to mother-to-child (vertical) transmission of hepatitis C virus (HCV), it is timely to draw up guidelines for the clinical management of HCV infected pregnant women and their children. METHODS: A review of evidence from the European Paediatric HCV Network (EPHN) prospective study of HCV infected women and their children and other published studies. Meeting of EPHN clinical experts to reach a consensus on recommendations for management. Each recommendation was graded according to the level of evidence. RESULTS/CONCLUSIONS: Although several risk factors for mother-to-child transmission have been identified, none are modifiable and there are currently no interventions available to prevent vertical transmission of HCV. Data on timing of loss of maternal antibodies and reliability of diagnostic tests inform the optimum follow-up schedule for confirmation or exclusion of infection in children born to HCV infected women. Based on the current evidence, routine antenatal screening for HCV should not be introduced and neither elective caesarean section nor avoidance of breastfeeding should be recommended to HCV infected women to prevent mother-to-child transmission of HCV. HCV/HIV co-infected women should follow existing HIV guideline

    The management of HCV infected pregnant women and their children European paediatric HCV network

    No full text
    BACKGROUND/AIMS: As evidence accumulates relating to mother-to-child (vertical) transmission of hepatitis C virus (HCV), it is timely to draw up guidelines for the clinical management of HCV infected pregnant women and their children. METHODS: A review of evidence from the European Paediatric HCV Network (EPHN) prospective study of HCV infected women and their children and other published studies. Meeting of EPHN clinical experts to reach a consensus on recommendations for management. Each recommendation was graded according to the level of evidence. RESULTS/CONCLUSIONS: Although several risk factors for mother-to-child transmission have been identified, none are modifiable and there are currently no interventions available to prevent vertical transmission of HCV. Data on timing of loss of maternal antibodies and reliability of diagnostic tests inform the optimum follow-up schedule for confirmation or exclusion of infection in children born to HCV infected women. Based on the current evidence, routine antenatal screening for HCV should not be introduced and neither elective caesarean section nor avoidance of breastfeeding should be recommended to HCV infected women to prevent mother-to-child transmission of HCV. HCV/HIV co-infected women should follow existing HIV guidelines

    Going Beyond Counting First Authors in Author Co-citation Analysis

    Full text link
    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

    Full text link
    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

    Full text link
    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
    corecore