1,721,155 research outputs found
Gestational diabetes and childhood asthma in a racially diverse US pregnancy cohort
Full text linkBACKGROUND: Childhood asthma is a common chronic disease that likely has prenatal origins. Gestational diabetes alters maternal physiology and may influence fetal risk for childhood onset disease. However, the association between gestational diabetes and child asthma is not well characterized. OBJECTIVE: To investigate the association between gestational diabetes and wheeze/asthma at approximately 4 years of age in a racially diverse U.S. cohort. METHODS: We studied mother-child dyads enrolled prenatally in the Conditions Affecting Neurocognitive Development and Learning in Early Childhood study. Gestational diabetes was determined by medical chart review. At approximately 4 years of age, we assessed child respiratory outcomes including parent report of physician-diagnosed asthma (ever), current wheeze (symptoms within the past 12 months), and current asthma (physician diagnosis and/or medication or symptoms within the past 12 months). We used modified Poisson regression to assess associations of gestational diabetes and child respiratory outcomes, adjusting for maternal age, race, prenatal smoking, pre-pregnancy body mass index, parity, asthma history, socioeconomic status and infant sex. RESULTS: Among 1,107 women, 66% were African-American/Black. Six percent (n=62) had gestational diabetes documented during pregnancy. Gestational diabetes was associated with increased risk of physician-diagnosed asthma (adjusted risk ratio (RR) [95% Confidence Interval]: 2.13 [1.35, 3.38]; prevalence: 14%), current wheeze (RR: 1.85 [1.23, 2.78]; prevalence: 19%) and current asthma (RR: 2.01 [1.30, 3.10]; prevalence: 16%). CONCLUSIONS: Gestational diabetes was associated with increased risk of asthma and wheeze outcomes. Additional studies are needed to elucidate modifiable pathways underlying this association
Genome‐wide association study reveals a novel locus for asthma with severe exacerbations in diverse populations
Full text linkBACKGROUND: Severe asthma exacerbations are a major cause of asthma morbidity and increased healthcare costs. Several studies have shown racial and ethnic differences in asthma exacerbation rates. We aimed to identify genetic variants associated with severe exacerbations in two high-risk populations for asthma.
METHODS: A genome-wide association study of asthma in children and youth with severe exacerbations was performed in 1283 exacerbators and 2027 controls without asthma of Latino ancestry. Independent suggestive variants (P ≤ 5 × 10-6 ) were selected for replication in 448 African Americans exacerbators and 595 controls. Case-only analyses were performed comparing the exacerbators with additional 898 Latinos and 524 African Americans asthma patients without exacerbations, while adjusting by treatment category as a proxy of asthma severity. We analyzed the functionality of associated variants with in silico methods and by correlating genotypes with methylation levels in whole blood in a subset of 473 Latinos.
RESULTS: We identified two genome-wide significant associations for susceptibility to asthma with severe exacerbations, including a novel locus located at chromosome 2p21 (rs4952375, odds ratio = 1.39, P = 3.8 × 10-8 ), which was also associated with asthma exacerbations in a case-only analysis (odds ratio = 1.25, P = 1.95 × 10-3 ). This polymorphism is an expression quantitative trait locus of the long intergenic non-protein coding RNA 1913 (LINC01913) in lung tissues (P = 1.3 × 10-7 ) and influences methylation levels of the protein kinase domain-containing cytoplasmic (PKDCC) gene in whole-blood cells (P = 9.8 × 10-5 ).
CONCLUSION: We identified a novel susceptibility locus for severe asthma exacerbations in Hispanic/Latino and African American youths with functional effects in gene expression and methylation status of neighboring genes
Stand der Asthmaepidemiologie - eine Zusammenstellung und Qualitätsanalyse systematischer Übersichtsarbeiten
No full textSeit Beginn der 1990er Jahre werden zunehmend systematische Übersichtsarbeiten veröffentlicht, die die Asthmaursache untersuchen. Trotz allem ist die Ursache der Asthmaerkrankung noch nicht vollständig verstanden. Diverse Risikofaktoren wurden bereits gefunden und diskutiert. Bei der Vielzahl an Veröffentlichungen ist eine Übersicht über den Stand der Forschung mittlerweile jedoch kaum noch möglich. Aufgrund dessen hat sich diese Arbeit zum Ziel gesetzt, die bisher veröffentlichten systematischen Übersichtsarbeiten zusammenzufassen und diese hinsichtlich ihrer Qualität zu bewerten. Es liegen bereits Publikationen mit ähnlicher Zielsetzung vor, jedoch wurden in diesen einige Einschränkungen bezüglich Thematik und Asthmaformen festgelegt. Die vorliegende Arbeit soll daher einen umfassenden Überblick über die Anzahl und Qualität bisher veröffentlichter systematischer Übersichtsarbeiten bezüglich Asthmaursache geben. Weiterhin soll sie dabei zukünftigen Publikationen in der Asthmaepidemiologie als Hilfestellung dienen.
Zunächst erfolgte eine Suche in Pudmed und EMABSE bis Dezember 2014. Insgesamt wurden 307 Artikel eingeschlossen, die mit Hilfe des AMSTAR-Kataloges sowie der Extraktion weiterer ausgewählter Informationen evaluiert wurden.
Im Zuge der Einordnung und Bewertung der Artikel zeigte sich, dass bereits eine Vielzahl von potenziell Asthma-relevanten Faktoren umfassend und mehrfach in Form systematischer Übersichtsarbeiten thematisiert wurde. Insbesondere Artikel, die genetische Aspekte der Asthmaerkrankung als Ursache beleuchten, verzeichnen seit den Anfängen des 21.Jahrhunderts einen starken Zuwachs. Auf Seiten der Qualität der Artikel ist anzumerken, dass auch hier auf Basis der AMSTAR-Einschätzung ein klarer Aufwärtstrend zu erkennen ist. Jedoch wird auch deutlich, dass die Ursache von Asthma sehr vielschichtig zu sein scheint. Dies erschwert die Suche nach der Primärprävention der Erkrankung.
Zudem stellt die Operationalisierung des Asthma-Begriffs eine weitere Problematik dar. Die Methode der Diagnosestellung variiert teils stark zwischen einzelnen Studien, da diese nicht eindeutig in Leitlinien formuliert ist. Demzufolge werden ungleiche Formen der Diagnosefindung angewandt, wie z.B. die durch einen Arzt, das Einnehmen von Asthmamedikamenten oder das Vorhandensein von asthmatischen Beschwerden. Diese Varianz hat eine erschwerte Vergleichbarkeit der Ergebnisse zur Folge, was die Aussagekraft von systematischen Übersichtsarbeiten abschwächt. Für zukünftige Studien und Übersichtsarbeiten im Bereich der Asthmaepidemiologie ist demzufolge eine einheitliche Diagnoseform der Erkrankung erstrebenswert.
Auch wenn sich die bisherige Datenlage zur Asthmaepidemiologie bereits vielseitig präsentiert, sind dennoch weitere randomisierte kontrollierte Studien (RCT) nötig, um asthmabezogene Einflussfaktoren weiter bekräftigen zu können. Bisher liegen viele Beobachtungsstudien vor, deren Aussagekraft hinter der von vergleichbaren RCT’s zurückbleibt. Thematisch wird in den aktuellsten systematischen Übersichtsarbeiten empfohlen, den Fokus zukünftiger Arbeiten vermehrt auf Gen-Umwelt-Faktoren zu setzen. Außerdem sollten beeinflussbare Faktoren, wie z.B. ernährungsbedingte oder psychologische Aspekte, weitergehend untersucht werden.
Die Ergebnisse dieser Arbeit wurden auf der Jahrestagung der Deutschen Gesellschaft für Epidemiologie 2016 in München vorgestellt und in zwei Artikeln in begutachteten wissenschaftlichen Fachzeitschriften im open access Verfahren veröffentlicht und so der Allgemeinheit zugänglich gemacht.
Die Veröffentlichungen beinhalten Excel-Tabellen, in denen die komplette, verschlagwortete Liste von eingeschlossenen systematischen Übersichtsarbeiten inklusive der AMSTAR-Scores enthalten ist
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
How often are children affected by acute respiratory infections? : frequency and symptom burden of acute respiratory infections in the first two years of life by using symptom diaries in the LöwenKIDS study
Full text linkBackground: Most acute respiratory infections (ARI) during childhood are not severe, but they cause a high disease burden. We want to give an overview of birth cohort studies using symptom diaries to recordARI, determine the frequency of ARI and identify risk factors. Methods: First, we conducted a scoping review to identify all birth cohorts. Second, we analyzed all ARI in a sample of participants (n=288; 37%), with almost complete diary entries from our LöwenKIDS birth cohort study. Results: We found 22 birth cohort studies worldwide using symptom diaries starting from birth to identify ARI. In our study, on average 13.7 ARI (median: 14.0, IQR: 10-17) were reported in the first two years of life. Attending daycare and having siblings were associated with an increased frequency of ARI. Conclusion: We give an overview of birth cohort studies and provide insight into the symptom burden of ARI in children during the first two years of life.Hintergrund: Akute respiratorische Infektionen (ARI) sind im Kindesalter mit einer hohen Krankheitslast verbunden. Ziel der Arbeit war es, einen Überblick über alle Geburtskohortenstudien mit Symptomtagebuch-Ansatz zur Erfassung von ARI und die Häufigkeit von ARI, sowie möglichen Risikofaktoren im Kindesalter zu identifizieren. Methoden: Zu Beginn wurde ein Scoping Review durchgeführt und anschließend Daten der LöwenKIDS-Kohorte, mit nahezu vollständigen Tagebucheinträgen (288, 37%) ausgewertet. Ergebnisse: Es konnten 22 Geburtskohorten weltweit identifiziert werden, die Symptomtagebücher ab der Geburt zur Bestimmung von ARI verwenden. Im Durchschnitt wurden 13,7 ARI (Median: 14,0, IQR: 10-17) in den ersten zwei Lebensjahren berichtet. Besuch einer Kindertagesstätte und Geschwisterkinder waren mit einem erhöhten Auftreten von ARI verbunden. Schlussfolgerung: Diese Arbeit gibt einen Überblick über Geburtskohortenstudien und erfasst die Häufigkeit der ARI in den ersten zwei Lebensjahren
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe 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
Anwendung der Bibliometrie und Altmetrik in der Kinderchirurgie
Full text link1. Bibliometric study in pediatric minimally invasive surgery (MIS)
Pediatric MIS is a standard technique worldwide for many pediatric surgical diseases and we aimed to analyze the research activity in this field. Articles on pediatric MIS (1991–2020) were analyzed from the Web of ScienceTM for the total number of publications, citations, journals, and IFs. Of these, the 50 most cited publications were evaluated in detail and classified according to the level of evidence (i.e., study design) and topic (i.e., surgical procedure). In total, 4464 publications and 53,111 citations from 684 journals on pediatric MIS were identified. The 50 most cited papers were published from 32 institutions in the USA/Canada (n = 28), Europe (n = 19), and Asia (n = 3) in 12 journals. Four authors (USA/Europe) contributed to 26% of the 50 most cited papers as first/senior author. Hot topics were laparoscopic pyeloplasty (n = 9), inguinal hernia repair (n = 7), appendectomy, and pyloromyotomy (n = 4 each). The majority of publications were retrospective studies (n = 33) and case reports (n = 6) (IF 5.2 ± 3.2; impact index 16.5 ± 6.4; citations 125 ± 39.4). They were cited as often as articles with high evidence levels (meta-analyses, n = 2; randomized controlled trials, n = 7; prospective studies, n = 2) (IF 12.9 ± 22.5; impact index 14.0 ± 6.5; citations 125 ± 34.7; p > 0.05).
2. Altmetric study in pediatric surgery
Altmetric analysis assessing online mentions of publications is a new method to evaluate awareness to research output. We aimed to identify and characterize the top 100 articles with the highest Altmetric Attention Score (AAS) in pediatric surgery. Publications from core pediatric surgical journals (J Pediatr Surg, J Pediatr Surg Case Rep, Eur J Pediatr Surg, European J Pediatr Surg Rep, Pediatr Surg Int, Semin Pediatr Surg) were retrieved from www.altmetric.com in January 2023 and the top 100 publications were identified. Characteristics of each publication were analyzed. Publications ranked 93 to 101 had an identical AAS of 21. Thus, 101 articles were included for further analysis. The top 101 AAS articles were published between 1974 and 2022, preferentially from the United States (64%) and mainly in J Pediatr Surg (73%), followed by J Pediatr Surg Case Rep, Pediatr Surg Int, Semin Pediatr Surg, and Eur J Pediatr Surg. Their AAS ranged between 21 and 389 (median 33) with X (formerly Twitter) being mostly responsible for online mentions (n=2189, 75%). The number of citations ranged from 0 to 358 (median 16) and did not correlate with the AAS. Retrospective study design (33%) with low evidence level IV (49%) was the dominant study type.
3. Conclusions
According to our bibliometric study in pediatric MIS, research activity increased over the last 30 years, with a golden decade in the early 21st century. Laparoscopic pyeloplasty and inguinal hernia repair accounted for most of the top 50 citations. Retrospective studies and case reports were the most common type of publication. Studies with high level of evidence such as randomized controlled trials are missing, especially on advanced techniques in pediatric MIS.
For our altmetric study of publications in core pediatric surgery journals, we analyzed the top 101 most mentioned pediatric surgery articles in six pediatric journals. Among the pediatric surgical journals, the Journal of Pediatric Surgery is the main source for high-profile publications in pediatric surgery. The altmetric score of articles is predominantly achieved by their propagation via X (formerly Twitter), irrespective of study design, level of evidence or recognition by the scientific community. Therefore, active “twitterism” may play the key role in reaching high AAS
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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