1,721,084 research outputs found
) cut‐offs
No full textBackground: Studies have reported that children who are obese are becoming more severely obese.
Objective: We aimed to classify obese children based on age- and gender-specific centile curves passing through body mass index (BMI) 30, 35 and 40 at age 18 as ‘class I’, ‘class II’ or severe, and ‘class III’ or morbid obesity.
Methods: In addition to the International Obesity Task Force BMI cut-offs corresponding to BMI 30 and 35, we calculated the BMI cut-offs corresponding to BMI 40 using the LMS method proposed by Cole and
Lobstein. We classified 217 obese children according to these criteria.
Results: Fifty-six (25.8%) children had class III obesity, 73 (33.6%) class II obesity and 88 (40.6%) class I obesity. Class III obese children had a higher waist circumference, systolic blood pressure and fasting insulinaemia compared with less obese children.
Conclusion: It is clinically important to classify obese children in different classes of obesity severity.We thank Prof. T. Cole for his advice on IOTF use and terminology. We thank Prof. Dr. Eric Caers for the language editing of the manuscript. LB analyzed the data, generated the tables and wrote the manuscript. GM conceived and designed the study, and critically revised the manuscript. Both authors participated in collecting the data and interpretation of the results. Both authors read and approved the final manuscript. This study is part of the Limburg Clinical Research Program (LCRP) UHasselt-ZOL-Jessa, supported by the foundation Limburg Sterk Merk, Hasselt University, Ziekenhuis Oost-Limburg and Jessa Hospital
Obese versus normal-weight children: a different plasma metabolic phenotype as determined by 1H-NMR spectroscopy
No full textBackground: Childhood obesity is a major health problem worldwide. Obese children are at high risk to develop co-morbidities such as cardiovascular dysfunction, type 2 diabetes, pulmonary, hepatic and renal complications1. To improve current prevention and treatment strategies for childhood obesity, a proper understanding of obesity-related pathophysiological mechanisms is required. Metabolomics is increasingly used as a tool for the study of obesity2. Aim: To investigate and compare the plasma metabolic profile of obese and normal-weight children as measured with 1H-NMR spectroscopy. Methods: Fasting plasma samples of 53 obese (mean age: 13.1 ± 2.2 yrs; mean BMI: 32.0 ± 4.5 kg/m²) and 28 normal-weight children (mean age: 13.1 ± 3.1 yrs; mean BMI: 18.9 ± 2.4 kg/m²) between 8 and 18 years of age were analysed by means of 1H-NMR spectroscopy. The 1H-NMR spectra were recorded on a 400 MHz Varian Inova spectrometer operating at 9.4 Tesla with a liquid-state PFG probe. Slightly T2-weighted spectra were acquired using a CPMG pulse sequence with water suppression. Spectra are phased manually, baseline corrected, and referenced to trimethylsilyl-2,2,3,3-tetradeuteropropionic acid (TSP) resonance at 0.015 ppm. The integration values of 110 spectral regions were normalized to the total integral area (except for TSP, water, glucose and fructose). Univariate analysis was performed by means of independent samples t test with correction for multiple testing by the Benjamini-Hochberg method. In addition, multivariate analysis by means of PCA and OPLS-DA was performed using SIMCA-P+ 12 (version 12.0, Umetrics, Umeå, Sweden). Results: The plasma metabolic profiles of obese children could be clearly distinguished from those of normal-weight children with a sensitivity of 100% and specificity of 93.9%. After correction for multiple testing, we observed 36 spectral regions to be significantly (p < 4.6 x 10-4) altered in obese children. Obese children showed higher levels of lipids (VLDL and LDL), unsaturated lipids, lactate and proline, and lower levels of citrate, asparagine, cysteine, α-ketoglutarate, myo-inositol, glucose and arginine as compared to normal-weight children. Conclusion: To our knowledge, this is the first study in which 1H-NMR spectroscopy is used as a tool to study childhood obesity. Our findings show that obese children clearly display a different plasma metabolic profile as compared to normal-weight children. In future, longitudinal research on a large sample population is needed in order to enable the discovery of obesity-related biomarkers.This study is part of the Limburg Clinical Research Program (LCRP) UHasselt-ZOL-Jessa, supported by the foundation Limburg Sterk Merk, Hasselt University, Ziekenhuis Oost-Limburg and Jessa Hospital
Differentiation of the plasma metabolite profile detected with 1H-NMR spectroscopy of obese and normal-weight children and adolescents
No full textBackground: Childhood obesity is a major health problem worldwide. Obese children are at high risk to develop co-morbidities such as cardiovascular dysfunction, type 2 diabetes, pulmonary, hepatic and renal complications. To improve current treatment strategies for childhood obesity, a proper understanding of obesity-related pathophysiological mechanisms is required. Metabolomics is increasingly used as a tool for the study of obesity, since the plasma metabolite profile is reflective of metabolic processes. Aim: To investigate and compare the metabolite profile of obese and normal-weight children detected with 1H-NMR spectroscopy. Methods: Fasting plasma samples of 20 obese (mean age: 13.4 ± 2.2 yrs; mean BMI: 33.6 ± 4.9 kg/m²) and 20 normal-weight children (mean age: 13.5 ± 2.9 yrs; mean BMI: 19.3 ± 2.3 kg/m²) between 8 and 18 years of age were analysed by means of 1H-NMR spectroscopy. The 1H-NMR spectra were recorded on a 400 MHz Varian Inova spectrometer operating at 9.4 Tesla with a standard liquid probe. Slightly T2-weighted spectra were acquired using a CPMG pulse sequence with water suppression. Spectra are phased manually, baseline corrected, and referenced to trimethylsilyl-2,2,3,3-tetradeuteropropionic acid (TSP) resonance at 0.015 ppm. The integration values of 110 spectral regions were normalized to the total integral area (except for TSP, water, glucose and fructose). These 110 variables were compared between obese and normal-weight children using Mann-Whitney U test. OPLS-DA multivariate analysis was applied (SIMCA-P+ 12, Umetrics, Umea, Sweden). Results: The plasma metabolite profiles of obese children could be clearly distinguished from those of normal-weight children. After correction for multiple testing, 19 spectral regions (p value < 4.545 x 10-4) were significantly different in obese compared with normal-weight children. Conclusions: Our findings show a clear differentiation between the plasma metabolite profile of obese and normal-weight children. However, additional research is needed in a larger sample population in order to translate current findings into a clinically meaningful outcome.This study is part of the Limburg Clinical Research Program (LCRP) UHasselt-ZOL-Jessa, supported by the foundation Limburg Sterk Merk, Hasselt University, Ziekenhuis Oost-Limburg and Jessa Hospital
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
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
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