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Identifying factors that influence the functional outcome is an important goal in schizophrenia research. The 22q11.2 deletion syndrome (22q11DS) is a unique genetic model with high risk (20–25%) for schizophrenia. This study aimed to identify potentially targetable domains of neurocognitive functioning associated with functional outcome in adults with 22q11DS.
We used comprehensive neurocognitive test data available for 99 adults with 22q11DS (n = 43 with schizophrenia) and principal component analysis to derive four domains of neurocognition (Verbal Memory, Visual and Logical Memory, Motor Performance, and Executive Performance). We then investigated the association of these neurocognitive domains with adaptive functioning using Vineland Adaptive Behavior Scales data and a linear regression model that accounted for the effects of schizophrenia status and overall intellectual level.
The regression model explained 46.8% of the variance in functional outcome (p < 0.0001). Executive Performance was significantly associated with functional outcome (p = 0.048). Age and schizophrenia were also significant factors. The effects of Executive Performance on functioning did not significantly differ between those with and without psychotic illness.
The findings provide the impetus for further studies to examine the potential of directed (early) interventions targeting Executive Performance to improve long-term adaptive functional outcome in individuals with, or at high risk for, schizophrenia. Moreover, the neurocognitive test profiles may benefit caregivers and clinicians by providing insight into the relative strengths and weaknesses of individuals with 22q11DS, with and without psychotic illness.
In September 2015, an outbreak of Escherichia coli Phage Type 32 with an indistinguishable multi locus variable number tandem repeat analysis profile was identified in Scotland. Twelve cases were identified; nine primary cases, two secondary and one asymptomatic case. Extensive food history investigations identified venison products containing wild venison produced by a single food business operator as the most likely source of the outbreak. Of the nine primary cases, eight had consumed venison products, and one case had not eaten venison themselves but had handled and cooked raw venison in the household. This was the first reported outbreak of Shiga toxin-producing Escherichia coli (STEC) linked to venison products in the UK, and was also notable due to the implicated products being commercially produced and widely distributed. In contrast, previous venison outbreaks reported from other countries have tended to be smaller and related to individually prepared carcases. The outbreak has highlighted some important knowledge gaps in relation to STEC in venison that are currently been investigated via a number of research studies.
The aim of the present work was to address experimentally the possible impact of exposure to air pollution during gestation on the differentiation and function of the gonads of the offspring using a rabbit model. Rabbits were exposed daily to diluted diesel exhaust gas or filtered air from the 3rd until the 27th day of gestation, during which time germ cells migrate in genital ridges and divide, and fetal sex is determined. Offspring gonads were collected shortly before birth (28th day of gestation) or after puberty (7.5 months after birth). The structure of the gonads was analyzed by histological and immunohistological methods. Serum concentrations of testosterone and anti-Müllerian hormone were determined using ELISA. The morphology and the endocrine function of the gonads collected just at the arrest of the exposure were similar in polluted and control animals in both sexes. No differences were observed as well in gonads collected after puberty. Sperm was collected at the head of the epididymis in adults. Sperm motility and DNA fragmentation were measured. Among all parameters analyzed, only the sperm DNA fragmentation rate was increased three-fold in exposed males. Mechanisms responsible for these modifications and their physiological consequences are to be further clarified.
Alterations in reinforcement-based decision making may be associated with increased psychiatric vulnerability in children who have experienced maltreatment. A probabilistic passive avoidance task and a model-based functional magnetic resonance imaging analytic approach were implemented to assess the neurocomputational components underlying decision making: (a) reinforcement expectancies (the representation of the outcomes associated with a stimulus) and (b) prediction error signaling (the ability to detect the differences between expected and actual outcomes). There were three main findings. First, the maltreated group (n = 18; mean age = 13), relative to nonmaltreated peers (n = 19; mean age = 13), showed decreased activity during expected value processing in a widespread network commonly associated with reinforcement expectancies representation, including the striatum (especially the caudate), the orbitofrontal cortex, and medial temporal structures including the hippocampus and insula. Second, consistent with previously reported hyperresponsiveness to negative cues in the context of childhood abuse, the maltreated group showed increased prediction error signaling in the middle cingulate gyrus, somatosensory cortex, superior temporal gyrus, and thalamus. Third, the maltreated group showed increased activity in frontodorsal regions and in the putamen during expected value representation. These findings suggest that early adverse environments disrupt the development of decision-making processes, which in turn may compromise psychosocial functioning in ways that increase latent vulnerability to psychiatric disorder.
Heritability estimates from twin studies of the multi-faceted phenotype of nicotine dependence (ND) range from moderate to high (31–60%), but vary substantially based on the specific ND-related construct examined. The current study estimated the aggregate role of common genetic variants on key ND constructs.
Genomic-relationship-matrix restricted maximum likelihood (GREML) was used to decompose phenotypic variance across multiple ND indices using 796 125 polymorphisms from 2346 unrelated ‘lifetime ever smokers’ of European ancestry. Measures included DSM-IV ND and Fagerström Test for Nicotine Dependence (FTND) summary measures and constituent constructs (e.g. withdrawal severity, tolerance, heaviness of smoking and time spent smoking). Exploratory and confirmatory factor models were used to describe the covariance structure across ND measures; resulting factor(s) were the subject(s) of GREML analyses.
Factor models indicated highly correlated DSM-IV and FTND factors for ND (0.545, 95% confidence interval 0.50–0.60) that could be represented as a higher-order factor (NIC DEP). Additive genetic influence on NIC DEP was 33% (s.e. = 0.14, p = 0.009). Post-hoc analyses indicated moderate genetic effects on the DSM-IV (34%, s.e. = 0.14, p = 0.008) and FTND (26%, s.e. = 0.14, p = 0.032) factors, both of which were influenced by the same genetic effects (rG-SNP = 1.00, s.e. = 0.09, p < 0.00001).
Overall, common single nucleotide polymorphisms accounted for a large proportion of the genetic influences on ND-related phenotypes that have been observed in twin studies. Genetic contributions across distinct ND scales were largely influenced by shared genetic factors.
Diethylstilbestrol (DES) is a non-steroidal estrogen that was commonly prescribed during pregnancy from the late 1940s to 1971. A potent endocrine disruptor, prenatal DES exposure has been linked with reproductive tract malformations, adverse pregnancy outcomes, cancer, infertility and earlier menopause. DES was used for years as a growth promoter in animal production. Some animal studies suggest that prenatal DES exposure is associated with obesity and metabolic disturbances. Using data from the National Cancer Institute DES Follow-Up Study, we evaluated the association between DES and adult obesity, weight gain from age 20 to mid-life, central adiposity and height among 2871 prenatally exposed and 1352 unexposed women between 23 and 52 years of age (median 41.5) at baseline in 1994. DES exposure status was confirmed by prenatal medical record review. We used multivariable log-binomial models to calculate risk ratios (RRs) for obesity in 2006, and linear regression to calculate mean differences in body mass index, weight gain, waist circumference and height. The adjusted RR for DES and obesity was 1.09 [95% confidence interval (CI): 0.97, 1.22], and RRs were 1.23 (CI: 1.07, 1.42) and 1.05 (CI: 0.91, 1.20) for low and high estimated total DES dose, respectively, compared with no exposure. DES-exposed women gained slightly more weight than unexposed women [mean difference, 0.70 kg (CI: −0.27, 1.66)]. This study suggests that prenatal DES exposure may be associated with a small increase in adult obesity.
Human campylobacteriosis exhibits a distinctive seasonality in temperate regions. This paper aims to identify the origins of this seasonality. Clinical isolates [typed by multi-locus sequence typing (MLST)] and epidemiological data were collected from Scotland. Young rural children were found to have an increased burden of disease in the late spring due to strains of non-chicken origin (e.g. ruminant and wild bird strains from environmental sources). In contrast the adult population had an extended summer peak associated with chicken strains. Travel abroad and UK mainland travel were associated with up to 17% and 18% of cases, respectively. International strains were associated with chicken, had a higher diversity than indigenous strains and a different spectrum of MLST types representative of these countries. Integrating empirical epidemiology and molecular subtyping can successfully elucidate the seasonal components of human campylobacteriosis. The findings will enable public health officials to focus strategies to reduce the disease burden.
During a 15-month period in Scotland a small but important number of human Campylobacter cases (3·2%) arose from 91 putative household outbreaks. Of the 26 outbreaks with known strain composition, 89% were composed of the same MLST which supports the potential use of MLST in public health epidemiology. The number of cases associated with household outbreaks is much larger than general outbreaks and there is some evidence to indicate that there may be secondary transmission, although this is relatively rare.
A point source outbreak of haemorrhagic colitis due to Escherichia coli O 157. H7 producing verocytotoxin (VT), took place following a christening party in Birmingham in June 1987. Twenty-six people were affected, six were admitted to hospital and one developed haemolytic uraemic syndrome: there were no deaths. VT + E. coli O 157. H7 was isolated from 13 (57%) of 23 faecal specimens from affected people and from 3 (9%) of 33 specimens from asymptomatic people. Free VT was detected in the faeces of one further asymptomatic person. Illness was associated with eating turkey-roll sandwiches (P < 0·001) suggesting that cold meats might be an important source of infection.
An outbreak of Salmonella enteritidis PT 6B food poisoning, the first reported of this recently described phage type, resulted in illness among 46 of 49 members of a camping group in North Wales. 33 of whom were hospitalized. Epidemiological evidence (P < 0·0001) indicated that a lemon meringue pie was the vehicle of infection. Fresh shell eggs, stored after purchase at ambient temperature, appear to be the most likely source of infection, with multiplication during preparation and subsequent storage of the pie a significant contributory factor. Campers may be at greater risk than others and should consider the use of cold boxes for the transport and storage of eggs, and avoid the preparation of lightly cooked egg products under these basic conditions.
An outbreak of Salmonella paratyphi B infection in the UK associated with a fish-and-chip shop is reported. The source of infection for the first three cases was believed to be a food handler who was infected overseas 6 years earlier. His wife whose faeces and urine were originally culture negative continued to run the shop but subsequently her faeces became positive on one occasion. She was considered to have been the source of two further cases, and secondary household spread of infection from these two cases resulted in one symptomatic and two asymptomatic infections. A second household contact of the proprietor also became a faecal excretor 2 months later. We recommend that food handlers living in households or in intimate contact with eases or carriers of S. paratyphi B should be put off work until all household contacts cease excreting the organism.
Scouring (diarrhoea) is a major concern for sheep producers as the accumulation of faecal material (dags) around the breech pre-disposes sheep to flystrike. Scouring occurs when the consistency of faeces is fluid with a low percentage of dry matter. In temperate areas such as the southern half of Australia, New Zealand and the United Kingdom, scouring is associated with ingestion of parasitic nematode larvae, mainly Teladorsagia circumcincta and Trichostrongylus colubriformis (Larsen et al., 1994). Breeding sheep to be resistant to these nematodes is a sustainable parasite-control strategy due to reduced reliance on chemical treatment. However, in adult sheep, scouring appears equally prevalent in resistant animals and, in some environments, is even more severe than in susceptible sheep (Karlsson et al., 2004). In this experiment, we investigated how faecal dry matter (FDM) in sheep from a flock bred for resistance to parasitic nematodes changed when challenged with infective larvae. We expected that FDM would be lower in challenged sheep compared to unchallenged controls, and FDM would also be lower in sheep with high dag scores compared to sheep with low dag scores.
Most thyroid cysts are benign; however, they require aspiration if symptomatic or atypical on ultrasound scanning, and ablation with ethanol injection if recurrent. We have systematically studied the use of new safety technologies for surgical procedures, which protect both the surgeon and the patient. Here, we describe the use of one such technology, the reciprocating procedure device, which enables simpler, safer, more efficient and less painful thyroid cyst aspiration and therapeutic ablation.
Male-sterile, female-fertile plants were used to produce hybrid soybean seed. Manual cross-pollination using male-sterile plants to produce large quantities of hybrid seed is difficult and time-consuming because of the low success rate in cross-pollination. Insect pollinators may be suitable vectors to transfer pollen, but the most suitable vector for pollen transfer from the male parent to the female parent has not been identified for soybean. The objective of the present study was to evaluate seed-set on four male-sterile, female-fertile soybean lines by using alfalfa leafcutting bees (Megachile rotundata (F.)) and honey bees (Apis mellifera (L.)) as pollinators. Seed-set was evaluated in summers 2003 and 2005 near Ames, Iowa, USA and in summers 2003, 2004, and 2005 near Wooster, Ohio, USA. Neither the effect of pollinator species nor the interaction effect of pollinator species×location was significant for any year. Honey bees performed similarly to alfalfa leafcutting bees at both locations. The results indicated significant differences for seed-set among male-sterile lines, suggesting preferential pollination. Male-sterile lines, ms1 (Urbana) and ms2 (Ames 2), had higher cross-pollinated seed-set compared to ms6 (Ames 1), and ms6 (Corsoy 79). At the Ames location, ms1ms1 (Urbana) plants had the highest seed-set (50·16 seeds per male-sterile plant in 2005). At the Wooster location, ms1ms1 (Urbana) plants also had the highest seed-set (92·04 seeds per male-sterile plant) in 2005. Costs and local conditions need to be addressed to support the choice of either pollinator species as a pollination vector to produce hybrid soybean seed.
Leaf mass per area (MA) is a central ecological trait that is intercorrelated with leaf life span, photosynthetic rate, nutrient concentration, and palatability to herbivores. These coordinated variables form a globally convergent leaf economics spectrum, which represents a general continuum running from rapid resource acquisition to maximized resource retention. Leaf economics are little studied in ancient ecosystems because they cannot be directly measured from leaf fossils. Here we use a large extant data set (65 sites; 667 species-site pairs) to develop a new, easily measured scaling relationship between petiole width and leaf mass, normalized for leaf area; this enables MA estimation for fossil leaves from petiole width and leaf area, two variables that are commonly measurable in leaf compression floras. The calibration data are restricted to woody angiosperms exclusive of monocots, but a preliminary data set (25 species) suggests that broad-leaved gymnosperms exhibit a similar scaling. Application to two well-studied, classic Eocene floras demonstrates that MA can be quantified in fossil assemblages. First, our results are consistent with predictions from paleobotanical and paleoclimatic studies of these floras. We found exclusively low-MA species from Republic (Washington, U.S.A., 49 Ma), a humid, warm-temperate flora with a strong deciduous component among the angiosperms, and a wide MA range in a seasonally dry, warm-temperate flora from the Green River Formation at Bonanza (Utah, U.S.A., 47 Ma), presumed to comprise a mix of short and long leaf life spans. Second, reconstructed MA in the fossil species is negatively correlated with levels of insect herbivory, whether measured as the proportion of leaves with insect damage, the proportion of leaf area removed by herbivores, or the diversity of insect-damage morphotypes. These correlations are consistent with herbivory observations in extant floras and they reflect fundamental trade-offs in plant-herbivore associations. Our results indicate that several key aspects of plant and plant-animal ecology can now be quantified in the fossil record and demonstrate that herbivory has helped shape the evolution of leaf structure for millions of years.
“The best books live by the appeal they make to the heart, even more than by the appeal they make to reason … [T]hey trouble the waters of sympathy within us, and keep them from stagnation.”
– W. J. Dawson, The Making of Manhood (1890)
Just such an appeal to the heart has made former Union General Lew Wallace's novel Ben-Hur a literary, stage, and film phenomenon for more than 120 years. In fact, as the historian Victor Davis Hanson observes, this was a book like no other previously published in America:
Wallace's novel began the strange nexus in American life, for good or ill, between literature, motion pictures, advertising, and popular culture. The novel led to the stage and then to the movies, but in the process it spun out entire ancillary industries of songs, skits, ads, clothes, and fan clubs, ensuring that within fifty years of its publication, nearly every American had heard the word “Ben-Hur” without necessarily ever reading the book.
When published in 1880, however, and long before it became a cultural phenomenon, Ben-Hur astounded and inspired readers with its pious affect. For many, it was probably the first and only novel they ever perused; such readers in fact considered it less an entertaining fiction and more a devotional text with which they could, and did, connect in a spiritually uplifting fashion.
Background. Although many studies have reported impairments of neurocognitive performance in patients with anorexia nervosa (AN), these have involved a wide range of assessment methods and some findings are inconsistent.
Method. Twenty-five female in-patients with a DSM-IV diagnosis of AN, identified from three units specializing in the treatment of eating disorders, volunteered for the study. Twenty-five non-clinical control subjects were recruited, matched for age, gender and estimated IQ. Subjects were assessed with a range of computer-administered neurocognitive tasks from the Cambridge Neuropsychological Test Automated Battery (CANTAB), which has been validated in many studies of neuropsychiatric disorders.
Results. The patient group showed significant but moderate impairments (i.e. less than one standard deviation below the mean performance of the control group) on tests of spatial recognition memory, a planning task and rapid visual information processing, while a subgroup of patients (n=14) showed greater degrees of impairments on at least one of these tests. The degrees of impairments did not correlate with body mass index (BMI). No impairments were observed on tests of spatial span, pattern recognition memory, spatial working memory, matching-to-sample, paired associates learning and set-shifting.
Conclusions. The findings, in relation to a mean BMI of 15·3, are compatible with, in general, subtle impairments in neurocognition in AN. However, in those patients with relatively severe degrees of impairments, these may have adverse effects on complex tasks of social and occupational functioning. Further research is needed on the nature of relevant causal mechanisms, including the effects of potentially confounding variables.