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1.
《Cell metabolism》2020,31(2):351-362.e5
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BackgroundNeuroblastoma, the most common extracranial solid tumor in children, contributes disproportionately to childhood cancer mortality and few risk factors have been identified. Our objective was to evaluate associations between parental and infant characteristics and neuroblastoma incidence.MethodsChildren born in Texas between January 1995 and December 2011 were eligible for the present study. Cases (N = 637) were diagnosed with neuroblastoma in Texas during the same period; controls (N = 6370) matched on year of birth were randomly selected from birth certificates that did not link to a record in the Texas Cancer Registry. We obtained data on birth and parental demographic/reproductive characteristics from birth certificates, and estimated odds ratios (OR) and 95% confidence intervals (CIs) for neuroblastoma using logistic regression.ResultsGestational age 34–36 weeks at birth was associated with neuroblastoma (OR 1.45, CI 1.09–1.90), whereas female sex was inversely associated (OR 0.68, CI 0.58–0.81). Relative to children of non-Hispanic White women, children of Hispanic (OR 0.53, CI 0.43–0.64) or non-Hispanic Black (OR 0.52, CI 0.38–0.71) women were at reduced odds of neuroblastoma. When maternal and paternal race/ethnicity were evaluated jointly, similar patterns were observed (two non-Hispanic Black parents: OR 0.55, 95%CI 0.36–0.79; two Hispanic parents: OR 0.53, 95%CI 0.41–0.67). Older maternal age was also positively associated with neuroblastoma (OR 1.41, CI 1.04–1.90 for 35–39 years; OR 1.62, CI 0.87–2.81 for ≥40 years, relative to 25–29 years).ConclusionsFindings provide further evidence of racial/ethnic disparities in neuroblastoma incidence, determinants of which are unknown. In contrast to most published studies, we observed an association between maternal age and neuroblastoma. Further studies with more robust control for confounding are warranted.  相似文献   
3.
Debate concerning the social impact of obesity has been ongoing since at least the 1980s. Bioethicists, however, have been relatively silent. If obesity is addressed it tends to be in the context of resource allocation or clinical procedures such as bariatric surgery. However, prominent bioethicists Peter Singer and Dan Callahan have recently entered the obesity debate to argue that obesity is not simply a clinical or personal issue but an ethical issue with social and political consequences. This article critically examines two problematic aspects of Singer and Callahan's respective approaches. First, there is an uncritical assumption that individuals are autonomous agents responsible for health‐related effects associated with food choices. In their view, individuals are obese because they choose certain foods or refrain from physical activity. However, this view alone does not justify intervention. Both Singer and Callahan recognize that individuals are free to make foolish choices so long as they do not harm others. It is at this point that the second problematic aspect arises. To interfere legitimately in the liberty of individuals, they invoke the harm principle. I contend, however, that in making this move both Singer and Callahan rely on superficial readings of public health research to amplify the harm caused by obese individuals and ignore pertinent epidemiological research on the social determinants of obesity. I argue that the mobilization of the harm principle and corresponding focus on individual behaviours without careful consideration of the empirical research is itself a form of harm that needs to be taken seriously.  相似文献   
4.
《Cell reports》2020,30(6):1835-1847.e9
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Childhood obesity is becoming a topic of great concern due to the rising prevalence of this condition in North America. Studies conducted in the United States have indicated that the prevalence of obesity has increased dramatically over the past few decades. The purpose of this study was to estimate the prevalence of obesity in Canadian children between the ages of 5 and 12 years by examining data from two national and two regional surveys. The 85th percentiles of each of four anthropometric indices derived from large normative populations were used as diagnostic criteria for obesity. As expected, the resulting prevalences varied according to the criteria used. A significant increase in childhood obesity between the 1981 to 1988 national surveys was observed when the three indices which used skinfolds were applied. Weight-for-height percentiles did not indicate an increase in obesity in these samples. Regional samples showed a less than expected prevalence of obesity among the middle-class children and a higher than expected rate among the inner city boys. It can be concluded that there is a need for a defined criteria for identifying obesity in children in order to avoid confusion resulting from the wide variation in estimates of prevalence resulting from different standards and measurements. Using adiposity-based criteria for obesity it was clearly evident that the prevalence of obesity has increased in Canadian children.  相似文献   
8.
ABSTRACT

Background: The disruption of circadian rhythm has been found to associate with obesity in vivo and in vitro. Sleep duration, eating habits, total feeding time, and nightshift work can also affect circadian rhythms. This study investigated the association between misalignment of circadian rhythm and obesity in Korean men, using a cross-sectional database.

Methods: This study used data from the Korean National Health and Nutrition Examination Survey (KNHANES), whose study population was 3,658 men aged 18 to 60 years. General and abdominal obesity was defined as a body mass index (BMI) ≥ 25 kg/m2 and waist circumference ≥ 90 cm, respectively. Circadian rhythm factors were determined with a self-report questionnaire and included breakfast frequency, sleep duration, and work time. Frequency of breakfast was divided into regular breakfast (five to seven times a week) and irregular breakfast (less than five times a week). Sleep duration was divided into less than 7 hours, 7–9 hours, and over 9 hours. Working time was defined as day/evening, night shift, and other type. The adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for general and abdominal obesity were calculated using multivariable logistic regression according to the number of factors that disturb the circadian rhythm.

Results: Participants with 1 (aOR 1.34, 95% Cl 1.10–1.61) and ≥2 (aOR 1.62, 95% Cl 1.29–2.05) factors disturbing circadian rhythms were associated with elevated risk for general obesity. Similarly, those with 1 (aOR 1.33, 95% Cl 1.09–1.63) and ≥2 (aOR 1.70, 95% Cl 1.32–2.20) factors had elevated risk for abdominal obesity.

Conclusions: Factors disturbing the circadian rhythm were associated with general and abdominal obesity. Additional studies are needed, and associations with metabolic diseases should be investigated.  相似文献   
9.
Obesity causes serious medical complications and impairs quality of life. Moreover, in older persons, obesity can exacerbate the age‐related decline in physical function and lead to frailty. However, appropriate treatment for obesity in older persons is controversial because of the reduction in relative health risks associated with increasing body mass index and the concern that weight loss could have potential harmful effects in the older population. This joint position statement from the American Society for Nutrition and NAASO, The Obesity Society reviews the clinical issues related to obesity in older persons and provides health professionals with appropriate weight‐management guidelines for obese older patients. The current data show that weight‐loss therapy improves physical function, quality of life, and the medical complications associated with obesity in older persons. Therefore, weight‐loss therapy that minimizes muscle and bone losses is recommended for older persons who are obese and who have functional impairments or medical complications that can benefit from weight loss.  相似文献   
10.
Measurements of the tissue accumulation of α-amino[1-14C]isobutyrate [1-14C]AIB) in lean (+/?) and obese (fa/fa) Zucker rats showed an augmented tissue/plasma ratio in the liver of the obese animals. In contrast, brown adipose tissue AIB accumulation was lower in the fa/fa animals. In response to a 24h starvation period AIB accumulation was significantly elevated in the liver and plasma of the lean animals and was unchanged in the liver of the fa/fa animals. The circulating concentration of alanine and branched-chain amino acids was elevated in the fa/fa animals as compared to their lean counterparts. These observations suggest that amino acid uptake is not involved in the impaired muscle development observed in the obese Zucker rat and that the ability of brown adipose tissue for amino acid utilization is decreased in the obese animals suggesting that this may partially explain the impaired thermoregulatory capacity observed in brown adipose tissue of obese Zucker rats.  相似文献   
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