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Few studies have derived data-driven dietary patterns in youth in the United States (US). This study examined data-driven dietary patterns and their associations with BMI measures in predominantly low-income, racial/ethnic minority US youth. Data were from baseline assessments of the four Childhood Obesity Prevention and Treatment Research (COPTR) Consortium trials: NET-Works (N=534; 2–4-year-olds), GROW (N=610; 3–5-year-olds), GOALS (N=241; 7–11-year-olds), and IMPACT (N=360; 10–13-year-olds). Weight and height were measured. Children/adult proxies completed 3 24-hour dietary recalls. Dietary patterns were derived for each site from 24 food/beverage groups using k-means cluster analysis. Multivariable linear regression models examined associations of dietary patterns with BMI and percentage of the 95th BMI percentile. Healthy (produce and whole grains) and Unhealthy (fried food, savory snacks, and desserts) patterns were found in NET-Works and GROW. GROW additionally had a dairy and sugar-sweetened beverage based pattern. GOALS had a similar Healthy pattern and a pattern resembling a traditional Mexican diet. Associations between dietary patterns and BMI were only observed in IMPACT. In IMPACT, youth in the Sandwich (cold cuts, refined grains, cheese, and miscellaneous [e.g., condiments]) compared to Mixed (whole grains and desserts) cluster had significantly higher BMI [β=0.99 (95% CI: 0.01, 1.97)] and percentage of the 95th BMI percentile [β=4.17 (95% CI: 0.11, 8.24)]. Healthy and Unhealthy patterns were the most common dietary patterns in COPTR youth, but diets may differ according to age, race/ethnicity, or geographic location. Public health messages focused on healthy dietary substitutions may help youth mimic a dietary pattern associated with lower BMI.
As colleges and universities respond to the COVID-19 outbreak, many in the media call it unprecedented. This is not the first time that institutions of higher education have had to respond to an epidemic, however. A historical review of college and university reactions to illnesses such as yellow fever and the 1918 influenza pandemic provides prior examples of institutional responses to epidemic diseases.
The utility of questionnaire based self-report measures for non-clinical psychotic symptoms is unclear and there are few reliable data about the nature and prevalence of these phenomena in children. The study aimed to investigate psychosis-like symptoms (PLIKS) in children utilizing both self-report measures and semi-structured observer rated assessments.
The study was cross-sectional; the setting being an assessment clinic for members of the ALSPAC birth cohort in Bristol, UK. 6455 respondents were assessed over 21 months, mean age 12.9 years. The main outcome measure was: 12 self-report screening questions for psychotic symptoms followed by semi-structured observer rated assessments by trained psychology graduates. The assessment instrument utilised stem questions, glossary definitions, and rating rules adapted from DISC-IV and SCAN items.
The 6-month period prevalence for one or more PLIKS rated by self-report questions was 38.9 % (95% CI = 37.7-40.1). Prevalence using observer rated assessments was 13.7% (95% CI = 12.8-14.5). Positive Predictive Values for the screen questions versus observer rated scores were low, except for auditory hallucinations (PPV=70%; 95% CI = 67.1-74.2). The most frequent observer rated symptom was auditory hallucinations (7.3%); in 18.8% of these cases symptoms occurred weekly or more. The prevalence of DSM-IV ‘core’ schizophrenia symptoms was 3.62%. Rates were significantly higher in children with low socio-economic status.
With the exception of auditory hallucinations, self-rated questionnaires are likely to substantially over-estimate the frequency of PLIKS in 12-year-old children. However, more reliable observer rated assessments reveal that PLIKS occur in a significant proportion of children.
To describe snacking characteristics and patterns in children and examine associations with diet quality and BMI.
Children’s weight and height were measured. Participants/adult proxies completed multiple 24 h dietary recalls. Snack occasions were self-identified. Snack patterns were derived for each sample using exploratory factor analysis. Associations of snacking characteristics and patterns with Healthy Eating Index-2010 (HEI-2010) score and BMI were examined using multivariable linear regression models.
Childhood Obesity Prevention and Treatment Research (COPTR) Consortium, USA: NET-Works, GROW, GOALS and IMPACT studies.
Two snack patterns were derived for three studies: a meal-like pattern and a beverage pattern. The IMPACT study had a similar meal-like pattern and a dairy/grains pattern. A positive association was observed between meal-like pattern adherence and HEI-2010 score (P for trend < 0⋅01) and snack occasion frequency and HEI-2010 score (β coefficient (95 % CI): NET-Works, 0⋅14 (0⋅04, 0⋅23); GROW, 0⋅12 (0⋅02, 0⋅21)) among younger children. A preference for snacking while using a screen was inversely associated with HEI-2010 score in all studies except IMPACT (β coefficient (95 % CI): NET-Works, −3⋅15 (−5⋅37, −0⋅92); GROW, −2⋅44 (−4⋅27, −0⋅61); GOALS, −5⋅80 (−8⋅74, −2⋅86)). Associations with BMI were almost all null.
Meal-like and beverage patterns described most children’s snack intake, although patterns for non-Hispanic Blacks or adolescents may differ. Diets of 2–5-year-olds may benefit from frequent meal-like pattern snack consumption and diets of all children may benefit from decreasing screen use during eating occasions.
The pine bark adelgid, Pineus strobi (Hartig) (Hemiptera: Adelgidae), is an herbivore native to eastern North America that specialises on eastern white pine, Pinus strobus Linnaeus (Pinaceae). Little is known about P. strobi, especially in its southern range in the Appalachian Mountains, United States of America, and the composition of its predator complex has not yet been documented in this region. The current study identifies arthropod predators associated with P. strobi in Appalachian forests of Virginia based on a two-year survey. Predators were identified using morphology and DNA barcoding. Predator species include: Laricobius rubidus LeConte (Coleoptera: Derodontidae), Leucopis piniperda Malloch (Diptera: Chamaemyiidae), and Leucopis argenticollis Zetterstedt (Diptera: Chamaemyiidae), that are known adelgid specialists. Also found were predators from the families Cecidomyiidae (Diptera), Coccinellidae (Coleoptera), Chrysopidae (Neuroptera), Hemerobiidae (Neuroptera), and Syrphidae (Diptera). The Cecidomyiidae were especially diverse, with 14 different species inferred from their DNA barcodes. Knowledge of this predator complex is particularly valuable for anticipation and detection of potential interactions between native predator species and those that are being considered for the introduction for biological control of invasive adelgid pests within the southern Appalachian ecosystem.
A controversy at the 2016 IUCN World Conservation Congress on the topic of closing domestic ivory markets (the 007, or so-called James Bond, motion) has given rise to a debate on IUCN's value proposition. A cross-section of authors who are engaged in IUCN but not employed by the organization, and with diverse perspectives and opinions, here argue for the importance of safeguarding and strengthening the unique technical and convening roles of IUCN, providing examples of what has and has not worked. Recommendations for protecting and enhancing IUCN's contribution to global conservation debates and policy formulation are given.
The challenges faced in the analysis of high-throughput sequencing data are discussed so frequently that the issues have become palpable stereotypes. Phrases such as ‘data deluge’, ‘hockey stick graph’ and ‘bioinformatics bottleneck’ are ubiquitous to the point of spawning an internet bingo card of overused sound bytes for audiences to check off during seminars (http://bit.ly/wYNxrF). Yet for all the discussion of these challenges, the dialogue about potential solutions is ignored or wildly speculative. In the sequencing world, the game is changing and no one knows how to make the next play. Computational pipelines progress slowly compared to the pace of sequencing technology, with each new platform requiring updated iterations of code and new empirical tests of error rates and data formats.
In spite of the myriad challenges left to surmount, high-throughput sequencing has already transformed and accelerated the pace of biodiversity research. Our current bioinformatic capabilities have been hard-won: characterizing and grappling with fundamentally different sequencing chemistries and order-of-magnitude-increases in file size have required substantial initial investments. The infancy of high-throughput fields means that the current biological insights are rudimentary compared to the sophisticated, complex analyses that will become available over the next decade. Yet by simply investigating ecosystems from a new perspective (genome-scale and community-level exploration, versus the narrower genetic and taxonomic questions previously necessitated by lower throughput Sanger sequencing), we have instantly gained a transformative view of biodiversity and ecological processes. These fledgling insights are already unprecedented, and the steadily increasing breadth of computational tools continues to widen our capacity for integrative data analysis.
The birth and death of sequencing technologies
Researchers impact sequencing technology almost as much as sequencing technology drives research. The platform currently in vogue may quickly fall out of fashion when a better (and cheaper) option hits the market. Biomedical applications drive the market and design for sequencers, with many large-scale sequencing centres focusing their resources on clinical applications (BGI@UCDavis, the Broad Institute), or species of agricultural or economic importance (BGI's facilities in China). Although many ‘megasequencing’ projects focused on biodiversity are now underway (Table 7.1), more fundamental and blue-skies research questions are inherently at the mercy of the technology and protocols favoured across biomedical fields. The dominance of BGI and the falling cost of sequencing are also prompting a reshuffling of long-term visions for many core facilities.
The impact of oligofructose (OF) intake on stool frequency has not been clearly substantiated, while significant gastrointestinal (GI) symptoms have been reported in some individuals. The aim of the present study was to determine the effects of OF on stool frequency and GI symptoms in healthy adults. In an 8-week, randomised, double-blind, parallel-arm study, ninety-eight participants were provided with 16 g OF in yogurt and snack bars (twenty male and thirty female) or matching control foods (seventeen male and thirty-one female), to incorporate, by replacement, into their usual diets. Participants completed a daily online questionnaire recording stool frequency and rating four symptoms: bloating, flatulence, abdominal cramping and noise, each on a Likert scale from ‘0’ for none (no symptoms) to ‘6’ for very severe, with a maximum symptom intensity score of 24 (sum of severities from all four symptoms). Online 24 h dietary recalls were completed during pre-baseline and weeks 4, 6 and 8 to determine fibre intake. When provided with OF foods, fibre intake increased to 24·3 (sem 0·5) g/d from pre-baseline (12·1 (sem 0·5) g/d; P < 0·001). Stool frequency increased with OF from 1·3 (sem 0·2) to 1·8 (sem 0·2) stools per d in males and 1·0 (sem 0·1) to 1·4 (sem 0·1) stools per d in females during intervention weeks compared with pre-baseline (P < 0·05),but did not change for control participants (males: 1·6 (sem 0·2) to 1·8 (sem 0·2); females: 1·3 (sem 0·1) to 1·4 (sem 0·1)). Flatulence was the most commonly reported symptom. Mean GI symptom intensity score was higher for the OF group (3·2 (sem 0·3)) v. control (1·7 (sem 0·1)) (P < 0·01), with few participants reporting above moderate symptoms. No change in symptom intensity occurred over time. Consuming yogurt and snack bars with 16 g OF improves regularity in young healthy adults. However, GI symptoms, resulting from an increase in oligofructose intake, may not diminish with time.
Antimicrobial stewardship programs (ASPs) are a mechanism to ensure the appropriate use of antimicrobials. The extent to which ASPs are formally implemented in freestanding children's hospitals is unknown. The objective of this study was to determine the prevalence and characteristics of ASPs in freestanding children's hospitals.
We conducted an electronic survey of 42 freestanding children's hospitals that are members of the Children's Hospital Association to determine the presence and characteristics of their ASPs. For hospitals without an ASP, we determined whether stewardship strategies were in place and whether there were barriers to implementing a formal ASP.
We received responses from 38 (91%) of 42. Among responding institutions, 16 (38%) had a formal ASP, and 15 (36%) were in the process of implementing a program. Most ASPs (13 [81%] of 16) were started after 2007. The median number of full-time equivalents dedicated to ASPs was 0.63 (range, 0.1–1.8). The most common antimicrobials monitored by ASPs were linezolid, vancomycin, and carbapenems. Many hospitals without a formal ASP were performing stewardship activities, including elements of prospective audit and feedback (9 [41%] of 22), formulary restriction (9 [41%] of 22), and use of clinical guidelines (17 [77%] of 22). Antimicrobial outcomes were more likely to be monitored by hospitals with ASPs (100% vs 68%; P = .01), although only 1 program provided support for a data analyst.
Most freestanding children's hospitals have implemented or are developing an ASP. These programs differ in structure and function, and more data are needed to identify program characteristics that have the greatest impact.
To examine the use of vitamin D supplements during infancy among the participants in an international infant feeding trial.
Information about vitamin D supplementation was collected through a validated FFQ at the age of 2 weeks and monthly between the ages of 1 month and 6 months.
Infants (n 2159) with a biological family member affected by type 1 diabetes and with increased human leucocyte antigen-conferred susceptibility to type 1 diabetes from twelve European countries, the USA, Canada and Australia.
Daily use of vitamin D supplements was common during the first 6 months of life in Northern and Central Europe (>80 % of the infants), with somewhat lower rates observed in Southern Europe (>60 %). In Canada, vitamin D supplementation was more common among exclusively breast-fed than other infants (e.g. 71 % v. 44 % at 6 months of age). Less than 2 % of infants in the USA and Australia received any vitamin D supplementation. Higher gestational age, older maternal age and longer maternal education were study-wide associated with greater use of vitamin D supplements.
Most of the infants received vitamin D supplements during the first 6 months of life in the European countries, whereas in Canada only half and in the USA and Australia very few were given supplementation.
In a widely cited 2003 article, DiMasi, Hansen, and Grabowski estimated the cost of pharmaceutical research and development to be $1.1 billion (year 2000 U.S. dollars) per new medicine coming onto the market in 2001. They also estimate that this cost is going up at a real (inflation-adjusted) rate of 7.4% annually. According to these estimates, the innovation cost per new medicine today is about $2.1 billion (year 2000 U.S. dollars) or $2.65 billion (year 2010 U.S. dollars).
Historically, measurement of gastrointestinal transit time has required collection and X-raying of faecal samples for up to 7 d after swallowing radio-opaque markers; a tedious, labour-intensive technique for both subjects and investigators. Recently, a wireless motility capsule (SmartPill®), which uses gut pH, pressure and temperature to measure transit time, has been developed. This device, however, has not been validated with dietary interventions. Therefore, we conducted a controlled cross-over trial to determine whether the device could detect a significant difference in transit time after ten healthy subjects (five men and five women) consumed 9 g of wheat bran (WB) or an equal volume, low-fibre control for 3 d. A paired t test was used to determine differences in transit times. Colonic transit time decreased by 10·8 (sd 6·6) h (P = 0·006) on the WB treatment. Whole-gut transit time also decreased by 8·9 (sd 5·4) h (P = 0·02) after the consumption of WB. Gastric emptying time and small-bowel transit time did not differ between treatments. Despite encouraging results, the present study had several limitations including short duration, lack of randomisation and unusable data due to delayed gastric emptying of the capsule. With minimal participant burden, the SmartPill technology appears to be a potentially useful tool for assessing transit time after a dietary intervention. This technology could be considered for digestive studies with novel fibres and other ingredients that are promoted for gut health.
Adverse effects of maternal substance use during pregnancy on fetal development may increase risk of psychopathology.
To examine whether maternal use of tobacco, cannabis or alcohol during pregnancy increases risk of offspring psychotic symptoms.
A longitudinal study of 6356 adolescents, age 12, who completed a semi-structured interview for psychotic symptoms in the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort.
Frequency of maternal tobacco use during pregnancy was associated with increased risk of suspected or definite psychotic symptoms (adjusted odds ratio 1.20, 95% CI 1.05–1.37, P = 0.007). Maternal alcohol use showed a non-linear association with psychotic symptoms, with this effect almost exclusively in the offspring of women drinking >21 units weekly. Maternal cannabis use was not associated with psychotic symptoms. Results for paternal smoking during pregnancy and maternal smoking post-pregnancy lend some support for a causal effect of tobacco exposure in utero on development of psychotic experiences.
These findings indicate that risk factors for development of non-clinical psychotic experiences may operate during early development. Future studies of how in utero exposure to tobacco affects cerebral development and function may lead to increased understanding of the pathogenesis of psychotic phenomena.
Previous studies have suggested that impaired fetal and childhood growth
are associated with an increased risk of schizophrenia, but the
association of pre-adult growth with non-clinical psychotic symptoms
(psychosis-like symptoms) in children is not known.
To explore the associations of body size at birth and age 7.5 years with
childhood psychosis-like symptoms.
Prospective cohort of children followed up from birth to age 12: the
Data on 6000 singleton infants born after 37 weeks of gestation. A one
standard deviation increase in birth weight was associated with an 18%
reduction in the risk of definite psychosis-like symptoms after adjusting
for age and gestation (Odds ratio (OR) = 0.82, 95% CI = 0.73–0.92,
P = 0.001). This association was partly confounded by
maternal anthropometry, smoking during pregnancy, socioeconomic status
and IQ. A similar association was seen for birth length and
psychosis-like symptoms, which disappeared after controlling for birth
weight. There was little evidence for an association of 7-year height or
adiposity with psychosis-like symptoms.
Measures of impaired fetal, but not childhood, growth are associated with
an increased risk of psychosis-like symptoms in 12-year-olds.
Non-clinical psychosis-like symptoms (PLIKS) occur in about 15% of the population. It is not clear whether adverse events during early development alter the risk of developing PLIKS. We aimed to examine whether maternal infection, diabetes or pre-eclampsia during pregnancy, gestational age, perinatal cardiopulmonary resuscitation or 5-min Apgar score were associated with development of psychotic symptoms during early adolescence.
A longitudinal study of 6356 12-year-old adolescents who completed a semi-structured interview for psychotic symptoms in the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort. Prenatal and perinatal data were obtained from obstetric records and maternal questionnaires completed during pregnancy.
The presence of definite psychotic symptoms was associated with maternal infection during pregnancy [adjusted odds ratio (OR) 1.44, 95% confidence interval (CI) 1.11–1.86, p=0.006], maternal diabetes (adjusted OR 3.43, 95% CI 1.14–10.36, p=0.029), need for resuscitation (adjusted OR 1.50, 95% CI 0.97–2.31, p=0.065) and 5-min Apgar score (adjusted OR per unit decrease 1.30, 95% CI 1.12–1.50, p<0.001). None of these associations were mediated by childhood IQ score. Most associations persisted, but were less strong, when including suspected symptoms as part of the outcome. There was no association between PLIKS and gestational age or pre-eclampsia.
Adverse events during early development may lead to an increased risk of developing PLIKS. Although the status of PLIKS in relation to clinical disorders such as schizophrenia is not clear, the similarity between these results and findings reported for schizophrenia indicates that future studies of PLIKS may help us to understand how psychotic experiences and clinical disorders develop throughout the life-course.
Non-clinical psychotic symptoms appear common in children, but it is possible that a proportion of reported symptoms result from misinterpretation. There is a well-established association between pre-morbid low IQ score and schizophrenia. Psychosis-like symptoms in children may also be a risk factor for psychotic disorder but their relationship with IQ is unclear.
To investigate the prevalence, nature and frequency of psychosis-like symptoms in 12-year-old children and study their relationship with IQ.
Longitudinal study using the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort. A total of 6455 children completed screening questions for 12 psychotic symptoms followed by a semi-structured clinical assessment. IQ was assessed at 8 years of age using the Wechsler Intelligence Scale for Children (3rd UK edition).
The 6-month period prevalence for one or more symptoms was 13.7% (95% CI 12.8–14.5). After adjustment for confounding variables, there was a non-linear association between IQ score and psychosis-like symptoms, such that only those with below average IQ score had an increased risk of reporting such symptoms.
Non-clinical psychotic symptoms occur in a significant proportion of 12-year-olds. Symptoms are associated with low IQ and also less strongly with a high IQ score. The pattern of association with IQ differs from that observed in schizophrenia.
Sauropod dinosaurs were the largest terrestrial animals and their growth rates remain a subject of debate. By counting growth lines in histologic sections and relating bone length to body mass, it has been estimated that Apatosaurus attained its adult body mass of about 25,000 kg in as little as 15 years, with a maximum growth rate over 5000 kg/yr. This rate exceeds that projected for a precocial bird or eutherian mammal of comparable estimated body mass. An alternative method of estimating limb length and body mass for each growth line, and fitting the resulting age/mass data to the von Bertalanffy growth equation, yields a revised growth curve suggesting that Apatosaurus adult mass was reached by 70 years with a maximum growth rate of 520 kg/yr. This alternative method for growth rate determination can also be applied to histological studies of other sauropods. At only about half the mass of Apatosaurus, Janenschia took between 20 and 30 years to attain its adult size (over 14,000 kg). This result is supported by independent evidence of estimated bone apposition rates. Despite having an adult body mass greater than Apatosaurus, the titanosaurid Alamosaurus attained a mass over 32,000 kg within 45 years and a maximum growth rate of 1000 kg/yr. Titanosaurids may have been the fastest growing of all sauropods. Even so, sauropod growth rate estimates produced using the von Bertalanffy equation fall between those projected for reptiles and those for precocial birds of equivalent projected body mass. These results are comparable to those found for smaller dinosaurs, and suggest that sauropods grew at rates similar to other dinosaurs in spite of their great size.