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A literature review was carried out to identify pre and perinatal characteristics associated with variation in Apgar scores in population-based studies. The parameters identified in the literature search were included in the classical twin design study to estimate effects of pre and perinatal factors shared and nonshared by twins and to test for a contribution of genetic factors in 1- and 5-min Apgar scores in a large sample of Dutch monozygotic (MZ) and dizygotic (DZ) twins. The sample included MZ and DZ twins (N = 5181 pairs) recruited by the Netherlands Twin Register shortly after birth, with data on prenatal characteristics and Apgar scores at first and/or fifth minutes. The ordinal regression and structural equation modeling were used to analyze the effects of characteristics identified in the literature review and to estimate genetic and nongenetic variance components. The literature review identified 63 papers. Consistent with the review, we observed statistically significant effects of birth order, zygosity and gestational age (GA) for 1- and 5-min Apgar scores of both twins. Apgar scores are higher in first-born versus second-born twins and DZ first-born versus MZ first-born twins. Birth weight had an effect on the 5-min Apgar of the first born. Fetal presentation and mode of delivery had different effects on Apgar scores of first- and second-born twins. Parental characteristics and chorionicity did not have significant main effects on Apgar scores. The MZ twins’ Apgar correlations equaled the DZ Apgar correlations. Our analyses suggest that individual differences in 1- and 5-min Apgar scores are attributable to shared and nonshared pre and perinatal factors, but not to genotypic factors of the newborns. The main predictors of Apgar scores are birth order, zygosity, GA, birth weight, mode of delivery and fetal presentation.
Objective: The human gut microbiota has been demonstrated to be associated with a number of host phenotypes, including obesity and a number of obesity-associated phenotypes. This study is aimed at further understanding and describing the relationship between the gut microbiota and obesity-associated measurements obtained from human participants. Subjects/Methods: Here, we utilize genetically informative study designs, including a four-corners design (extremes of genetic risk for BMI and of observed BMI; N = 50) and the BMI monozygotic (MZ) discordant twin pair design (N = 30), in order to help delineate the role of host genetics and the gut microbiota in the development of obesity. Results: Our results highlight a negative association between BMI and alpha diversity of the gut microbiota. The low genetic risk/high BMI group of individuals had a lower gut microbiota alpha diversity when compared to the other three groups. Although the difference in alpha diversity between the lean and heavy groups of the BMI-discordant MZ twin design did not achieve significance, this difference was observed to be in the expected direction, with the heavier participants having a lower average alpha diversity. We have also identified nine OTUs observed to be associated with either a leaner or heavier phenotype, with enrichment for OTUs classified to the Ruminococcaceae and Oxalobacteraceae taxonomic families. Conclusion: Our study presents evidence of a relationship between BMI and alpha diversity of the gut microbiota. In addition to these findings, a number of OTUs were found to be significantly associated with host BMI. These findings may highlight separate subtypes of obesity, one driven by genetic factors, the other more heavily influenced by environmental factors.
Dietary nitrate has been shown to increase nitrate/nitrite levels and decrease blood pressure (BP) in multiple populations. There are few reports among hypertensives and these reports have provided conflicting evidence. We aimed to assess the effect of daily nitrate compared with placebo in subjects with uncontrolled hypertension (HTN). On day 0, hypertensives wore an ambulatory BP monitor (ABPM) for 24 h and blood was taken. Subjects were then randomised to 7-d nitrate-rich beetroot juice (NO3−) (12·9 mmol nitrate) followed by 7-d nitrate-depleted beetroot juice (0·5 mmol nitrate) or vice versa. ABPM and blood were assessed before and after both conditions. In all, twenty subjects with treated yet uncontrolled HTN entered and completed the trial (mean age=62·5 years, mean BMI=30·7 kg/m2). Baseline BP was 137/80 (sd 7/7) mmHg. Dietary nitrate was well tolerated and resulted in significantly increased plasma nitrite (P=0·0004) and decreased 24-h systolic BP and diastolic BP compared with placebo (−8 mmHg; P=0·012 and −4 mmHg; P=0·018, respectively). Our results support the existing data suggesting an anti-hypertensive effect of dietary nitrate in treated yet uncontrolled hypertensives. Targeted dietary strategies appear promising contributors to BP control.
Adolescence is a key time period for the emergence of psychosocial and mental health difficulties. To promote adolescent adaptive (‘resilient’) psychosocial functioning (PSF), appropriate conceptualisation and quantification of such functioning and its predictors is a crucial first step. Here, we quantify resilient functioning as the degree to which an individual functions better or worse than expected given their self-reported childhood family experiences, and relate this to adolescent family and friendship support.
We used Principal Component and regression analyses to investigate the relationship between childhood family experiences and PSF (psychiatric symptomatology, personality traits and mental wellbeing) in healthy adolescents (the Neuroscience in Psychiatry Network; N = 2389; ages 14–24). Residuals from the relation between childhood family experiences and PSF reflect resilient functioning; the degree to which an individual is functioning better, or worse, than expected given their childhood family experiences. Next, we relate family and friendship support with resilient functioning both cross-sectionally and 1 year later.
Friendship and family support were positive predictors of immediate resilient PSF, with friendship support being the strongest predictor. However, whereas friendship support was a significant positive predictor of later resilient functioning, family support had a negative relationship with later resilient PSF.
We show that friendship support, but not family support, is an important positive predictor of both immediate and later resilient PSF in adolescence and early adulthood. Interventions that promote the skills needed to acquire and sustain adolescent friendships may be crucial in increasing adolescent resilient PSF.
Deliberately lit vegetation fires have the greatest destructive potential of any intentionally lit blaze. The ‘Black Saturday’ bushfires of 7 February 2009 in Victoria, Australia, killed 173 people, injured 414 and destroyed 3500 buildings, including two entire towns (Teague et al, 2010). Even before the fires had abated, police and firefighters revealed that several had been deliberately lit (Silvester, 2009). The subsequent Royal Commission attributed four of the large fires to arson. These four fires caused 52 deaths and burnt approximately 2000 km2 of land, an area slightly larger than that of Greater London (Teague et al, 2010). The community was united in its outrage that anyone would intentionally set a bushfire, particularly on a day with the most severe fire danger rating in over 20 years. The question of why anyone would set such fires is, unfortunately, not easy to answer, as there has been little investigation of those who deliberately light bushfires, especially in Australia. The lack of research in this area is somewhat surprising, given that events like Black Saturday are not uncommon in Australia and other fire-prone regions. The Australian Institute of Criminology estimates that 25 000–30 000 bushfires are deliberately lit in Australia each year (Bryant, 2008). Disaster-level bushfires (those resulting in more than $10 million in damage) cost the Australian economy an annual average of $77 million, even before the associated costs of police and courts and the intangible human and social costs wrought by large fires are considered (Department of Infrastructure, Transport, Regional Development and Local Government, 2001). Estimates from the USA suggest that between 20% and 25% of wildfires are deliberately lit, with rates dependent on location (Federal Emergency Management Agency, 1994; Hall, 1998). Even in the UK, where vegetation fires rarely result in the type of widespread destruction seen elsewhere, it is thought that some 20% of fires in open countryside are the result of arson (Lewis, 1999).
In areas such as south-eastern Australia, where bushfire is a seasonal hazard responsible for significant property loss, there is little tolerance for deliberate firesetting. Public pressure on law-enforcement agencies and government to prevent bushfire arson is becoming increasingly intense.
There is a very limited literature linking firesetting with abnormalities in brain function. In this chapter we review the literature on the relevance of brain dysfunction and neuropathology in firesetting. We conducted Medline and PsycINFO searches on the neurobiology and neuropathology of firesetting. In summary, firesetting is largely associated with childhood conduct problems, antisocial personality pathology and alcohol misuse rather than with major mental illness. Although there are anecdotal reports of an association between organic brain syndromes and firesetting, most literature focuses on epilepsy and autistic-spectrum disorders and intellectual impairment. There are few studies investigating the neurobiology of arson, but available work points to evidence of reduced serotonergic function and a hypoglycaemic tendency in arsonists which appears to be associated with type 2 alcoholism. The neuropsychology of arson has not been extensively investigated, but one study suggests that arsonists may have greater impairments in executive function than do violent and sex offenders. We conclude that further work is needed to explore the neurobiology of firesetting and the potential roles of genes, environment and brain structure and function in the aetiology and maintenance of this behaviour.
Arson is a crime with significant impacts in terms of financial loss, serious injury and death (Geller, 1992, 2008; Barker, 1994; Gaynor, 1996). ‘Arson’ is a forensic/legal classification (Gaynor & Hatcher, 1987) referring to deliberate firesetting and using the key criteria of wilful and malicious motive and intent (Gaynor & Hatcher, 1987; Ritchie & Huff, 1999). The true extent of the problem is unknown, as it is often difficult to determine whether or not a fire has been deliberately set and only a small proportion of arson offences come to prosecution. Nonetheless, the incidence of arson appears to have increased in the USA and in most European countries in recent years (Prins, 1994; Räsänen et al, 1995; Soothill et al, 2004). In England and Wales there were 39 318 cases in 2007–08 (Home Office, 2008). ‘Firesetting’ is used to describe a broader range of fire-lighting behaviour, which may not involve the conscious intent to commit a crime (Barnett et al, 1999; Ritchie & Huff, 1999). ‘Firesetting’ is often used in the clinical literature to denote ‘fire-lighting’ in the absence of a diagnosis of pyromania.
The 71-s modulation in the light curve of the old nova DQ Her has a mean semi-amplitude of 1.8% at 2180 Å, although the amplitude varies by at least a factor of two from orbit to orbit. The disturbance in the amplitude and phase of the modulation during eclipses is similar to that observed at visual wavelengths. We conclude that at 2180 Å, as at visual wavelengths, the modulated flux is reprocessed and comes from the accretion disk.
One of the first stellar photometry programs completed with the High Speed Photometer (HSP) on the Hubble Space Telescope (HST) was visual and ultraviolet observations of the Crab pulsar. We obtained continuous observations on four consecutive days using a visual filter (4000 - 7000 Å) and an additional observation, approximately two months later, using an ultraviolet filter (1600 - 3000 Å). Each observation has a time resolution of 10.7 μsec and spans approximately 30 minutes in duration. In addition to the observations made with the HSP, contemporaneous UBVR observations were also made at Jodrell Bank and McDonald Observatory. Some of the more prominent results include the following: 1) the main pulse arrival time is the same in the UV as it is in the optical and the radio regions of the spectrum, 2) there is essentially no difference in the shape of the optical pulse from one observation to the next, 3) the “flatness” of the peak of the main pulse suggests that the main pulse has been resolved in time, and 4) in accordance with the trend of observations from the radio to infrared wavelengths, the main pulse is slightly narrower in the UV than in the optical.
A second HSP science observing program was a long-term program to monitor the eclipsing dwarf nova, Z Chamaeleontis (Porb = 107 minutes). We obtained a total of 42 observations of Z Cha in the UV (1120 - 1580 Å) each with a duration of approximately 45 minutes and separated by approximately three days. Although the majority of the observations cover the eclipse of the white dwarf and hot spot, a few observations were obtained outside-of-eclipse in order to obtain the complete light curve. During the course of this program, Z Cha underwent two “normal” outbursts in which the shape of the light curve changed dramatically. We will present a comparison of the light curve in quiescence with that during a “normal” outburst and quantify such geometrical and physical parameters as temperature and size of the white dwarf, hot spot, and accretion disk.
Changes in reflexive emotional responses are hallmarks of depression, but how emotional reflexes make an impact on adaptive decision-making in depression has not been examined formally. Using a Pavlovian-instrumental transfer (PIT) task, we compared the influence of affectively valenced stimuli on decision-making in depression and generalized anxiety disorder compared with healthy controls; and related this to the longitudinal course of the illness.
A total of 40 subjects with a current DSM-IV-TR diagnosis of major depressive disorder, dysthymia, generalized anxiety disorder, or a combination thereof, and 40 matched healthy controls performed a PIT task that assesses how instrumental approach and withdrawal behaviours are influenced by appetitive and aversive Pavlovian conditioned stimuli (CSs). Patients were followed up after 4–6 months. Analyses focused on patients with depression alone (n = 25).
In healthy controls, Pavlovian CSs exerted action-specific effects, with appetitive CSs boosting active approach and aversive CSs active withdrawal. This action-specificity was absent in currently depressed subjects. Greater action-specificity in patients was associated with better recovery over the follow-up period.
Depression is associated with an abnormal influence of emotional reactions on decision-making in a way that may predict recovery.
To characterize health professional schools by their vaccination policies for acceptable forms of evidence of immunity and exemptions permitted.
Data were collected between September 2011 and April 2012 using an Internet-based survey e-mailed to selected types of accredited health professional programs. Schools were identified through accrediting associations for each type of health professional program. Analysis was limited to schools requiring ≥1 vaccine recommended by the Advisory Committee on Immunization Practices (ACIP): measles, mumps, rubella, hepatitis B, varicella, pertussis, and influenza. Weighted bivariate frequencies were generated using SAS 9.3.
Of 2,775 schools surveyed, 75% (n=2,077) responded; of responding schools, 93% (1947) required ≥1 ACIP-recommended vaccination. The proportion of schools accepting ≥1 non–ACIP-recommended form of evidence of immunity varied by vaccine: 42% for pertussis, 37% for influenza, 30% for rubella, 22% for hepatitis B, 18% for varicella, and 9% for measles and mumps. Among schools with ≥1 vaccination requirement, medical exemptions were permitted for ≥1 vaccine by 75% of schools; 54% permitted religious exemptions; 35% permitted personal belief exemptions; 58% permitted any nonmedical exemption.
Many schools accept non–ACIP-recommended forms of evidence of immunity which could lead some students to believe they are protected from vaccine preventable diseases when they may be susceptible. Additional efforts are needed to better educate school officials about current ACIP recommendations for acceptable forms of evidence of immunity so school policies can be revised as needed.
The influence of genetic factors on major depressive disorder is lower than on other psychiatric disorders. Heritability estimates mainly derive from cross-sectional studies, and knowledge on the longitudinal aetiology of symptoms of anxiety and depression (SxAnxDep) across the lifespan is limited. We aimed to assess phenotypic, genetic and environmental stability in SxAnxDep between ages 3 and 63 years.
We used a cohort-sequential design combining data from 49 524 twins followed from birth to age ⩾20 years, and from adolescence into adulthood. SxAnxDep were assessed repeatedly with a maximum of eight assessments over a 25-year period. Data were ordered in 30 age groups and analysed with longitudinal genetic models.
Over age, there was a significant increase during adolescence in mean scores with sex differences (women>men) emerging. Heritability was high in childhood and decreased to 30–40% during adulthood. This decrease in heritability was due to an increase in environmental variance. Phenotypic stability was moderate in children (correlations across ages ~0.5) and high in adolescents (r = 0.6), young adults (r = 0.7), and adults (r = 0.8). Longitudinal stability was mostly attributable to genetic factors. During childhood and adolescence there was also significant genetic innovation, which was absent in adults. Environmental effects contributed to short-term stability.
The substantial stability in SxAnxDep is mainly due to genetic effects. The importance of environmental effects increases with age and explains the relatively low heritability of depression in adults. The environmental effects are transient, but the contribution to stability increases with age.