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Childhood adversities (CAs) predict heightened risks of posttraumatic stress disorder (PTSD) and major depressive episode (MDE) among people exposed to adult traumatic events. Identifying which CAs put individuals at greatest risk for these adverse posttraumatic neuropsychiatric sequelae (APNS) is important for targeting prevention interventions.
Data came from n = 999 patients ages 18–75 presenting to 29 U.S. emergency departments after a motor vehicle collision (MVC) and followed for 3 months, the amount of time traditionally used to define chronic PTSD, in the Advancing Understanding of Recovery After Trauma (AURORA) study. Six CA types were self-reported at baseline: physical abuse, sexual abuse, emotional abuse, physical neglect, emotional neglect and bullying. Both dichotomous measures of ever experiencing each CA type and numeric measures of exposure frequency were included in the analysis. Risk ratios (RRs) of these CA measures as well as complex interactions among these measures were examined as predictors of APNS 3 months post-MVC. APNS was defined as meeting self-reported criteria for either PTSD based on the PTSD Checklist for DSM-5 and/or MDE based on the PROMIS Depression Short-Form 8b. We controlled for pre-MVC lifetime histories of PTSD and MDE. We also examined mediating effects through peritraumatic symptoms assessed in the emergency department and PTSD and MDE assessed in 2-week and 8-week follow-up surveys. Analyses were carried out with robust Poisson regression models.
Most participants (90.9%) reported at least rarely having experienced some CA. Ever experiencing each CA other than emotional neglect was univariably associated with 3-month APNS (RRs = 1.31–1.60). Each CA frequency was also univariably associated with 3-month APNS (RRs = 1.65–2.45). In multivariable models, joint associations of CAs with 3-month APNS were additive, with frequency of emotional abuse (RR = 2.03; 95% CI = 1.43–2.87) and bullying (RR = 1.44; 95% CI = 0.99–2.10) being the strongest predictors. Control variable analyses found that these associations were largely explained by pre-MVC histories of PTSD and MDE.
Although individuals who experience frequent emotional abuse and bullying in childhood have a heightened risk of experiencing APNS after an adult MVC, these associations are largely mediated by prior histories of PTSD and MDE.
The impact of the coronavirus disease 2019 (COVID-19) pandemic on mental health is still being unravelled. It is important to identify which individuals are at greatest risk of worsening symptoms. This study aimed to examine changes in depression, anxiety and post-traumatic stress disorder (PTSD) symptoms using prospective and retrospective symptom change assessments, and to find and examine the effect of key risk factors.
Online questionnaires were administered to 34 465 individuals (aged 16 years or above) in April/May 2020 in the UK, recruited from existing cohorts or via social media. Around one-third (n = 12 718) of included participants had prior diagnoses of depression or anxiety and had completed pre-pandemic mental health assessments (between September 2018 and February 2020), allowing prospective investigation of symptom change.
Prospective symptom analyses showed small decreases in depression (PHQ-9: −0.43 points) and anxiety [generalised anxiety disorder scale – 7 items (GAD)-7: −0.33 points] and increases in PTSD (PCL-6: 0.22 points). Conversely, retrospective symptom analyses demonstrated significant large increases (PHQ-9: 2.40; GAD-7 = 1.97), with 55% reported worsening mental health since the beginning of the pandemic on a global change rating. Across both prospective and retrospective measures of symptom change, worsening depression, anxiety and PTSD symptoms were associated with prior mental health diagnoses, female gender, young age and unemployed/student status.
We highlight the effect of prior mental health diagnoses on worsening mental health during the pandemic and confirm previously reported sociodemographic risk factors. Discrepancies between prospective and retrospective measures of changes in mental health may be related to recall bias-related underestimation of prior symptom severity.
We developed a model and subsequently simulated robust white foxtail (Setaria viridis var. robusta-alba Schreiber) or robust purple foxtail (Setaria viridis var. robusta-purpurea Schreiber) growth. SETSIM (SETaria SIMulation) uses the GASP IV simulation language which allows for both continuously changing variables and discrete events. GASP IV provides the necessary integrations and automatic time-stepping essential in simulation. SETSIM uses the materials-flow concept to simulate foxtail growth and development on a population basis. Carbohydrate flow among six compartments (leaf, stem, and root total nonstructural carbohydrate pools; leaf, stem, and root tissue) is governed by nine physiological rates. Each rate is dependent on the physiological state of the foxtail population and the environmental conditions prevailing. Simulation of carbohydrate flow in and out of each compartment results in the net growth of that compartment. By considering all six compartments simultaneously, the vegetative growth and development of a foxtail population can be simulated. Validation of SETSIM with field data recorded over a 2-yr period has shown that this simulator can accurately predict foxtail growth parameters such as dry matter accumulation, plant height, leaf area index, and leaf to stem ratio. SETSIM could serve as a framework for other weed models because of its modular structure. Such models can benefit weed science by predicting the active stage of weed growth, predicting whether a weed could become a problem under different climatic conditions, interfacing with existing crop models to predict yield and harvest restriction, pointing out gaps in our present knowledge in weed biology, and serving as teaching aids.
Prior studies have suggested a relationship between atopy and mental health, although methodological barriers have limited the generalizability of these findings. The objective of this study was to investigate the relationship between early-life atopy and vulnerability to mental health problems among youth in the community.
Data were drawn from the Raine Study (N = 2868), a population-based birth cohort study in Western Australia. Logistic regression and generalized estimating equations were used to examine the relationship between atopy at ages 1–5 years [using parent report and objective biological confirmation (sera IgE)], and the range of internalizing and externalizing mental health problems at ages 5–17 years.
Atopy appears to be associated with increased vulnerability to affective and anxiety problems, compared to youth without atopy. These associations remained significant after adjusting for a range of potential confounders. No relationship was evident between atopy and attention deficit hyperactivity disorder or externalizing problems.
Findings are the first linking atopy (measured by both parent report and objective verification) with increased vulnerability to affective and anxiety problems. Therefore, replication is required. If replicated, future research aimed at understanding the possible biological and/or social and environmental pathways underlying these links is needed. Such information could shed light on shared pathways that could lead to more effective treatments for both atopy and internalizing mental health problems.
Impetigo is common in remote Indigenous children of northern Australia, with the primary driver in this context being Streptococcus pyogenes [or group A Streptococcus (GAS)]. To reduce the high burden of impetigo, the transmission dynamics of GAS must be more clearly elucidated. We performed whole genome sequencing on 31 GAS isolates collected in a single community from children in 11 households with ⩾2 GAS-infected children. We aimed to determine whether transmission was occurring principally within households or across the community. The 31 isolates were represented by nine multilocus sequence types and isolates within each sequence type differed from one another by only 0–3 single nucleotide polymorphisms. There was evidence of extensive transmission both within households and across the community. Our findings suggest that strategies to reduce the burden of impetigo in this setting will need to extend beyond individual households, and incorporate multi-faceted, community-wide approaches.
Non-typhoidal Salmonella is estimated to be the most common bacterial cause of foodborne illness in the United States, causing an estimated one million domestically acquired foodborne illnesses annually. Recent, large outbreaks have highlighted the importance of ground beef as an important source of multidrug-resistant Salmonella. We analysed the epidemiology of salmonellosis outbreaks that were attributed to beef in the United States reported to the Centers for Disease Control and Prevention (CDC) from 1973 to 2011. During 1973–2011, of the 1965 outbreaks of Salmonella where a food vehicle was implicated, 96 were attributed to beef, accounting for 3684 illnesses. We observed a shift in the type of beef implicated in salmonellosis outbreaks, from roast to ground beef. Delicatessen-style roast beef cooked in commercial processing establishments was the predominant type during the 1970s and early 1980s; regulations on cooking and processing essentially eliminated this problem by 1987. Ground beef emerged as an important vehicle in the 2000s; it was implicated in 17 (45%) of the 38 beef-attributed outbreaks reported during 2002–2011. Although this emergence was likely due in part to increased participation in CDC's PulseNet, which was established in 1996, and proactive decisions by the United States Department of Agriculture's Food Safety and Inspection Service, stronger measures are needed to decrease contamination of ground beef with Salmonella.
To identify risk factors for Clostridium difficile infection (CDI) in Danish patients consulting general practice with gastrointestinal symptoms, a prospective matched case-control study was performed; cases (N = 259) had positive cultures for toxigenic C. difficile and controls (N = 455) negative cultures. Data were analysed by conditional logistic regression. In patients aged ⩾2 years (138 cases), hospitalization [odds ratio (OR) 8·4, 95% confidence interval (CI) 3·1–23], consumption of beef (OR 5·5, 95% CI 2·0–15), phenoxymethylpenicillin (OR 15, 95% CI 2·7–82), dicloxacillin (OR 27, 95% CI 3·6–211), and extended spectrum penicillins (OR 9·2, 95% CI 1·9–45) were associated with CDI. In patients aged <2 years none of these were associated with CDI, but in a subgroup analysis contact with animals was associated with CDI (OR 8·1, 95% CI 1·0–64). This study emphasizes narrow-spectrum penicillins, and suggests beef consumption, as risk factors for CDI in adults, and indicates a different epidemiology of CDI in infants.
The combustion synthesis of the common ferroelectric material, BaTiO3, was developed using the stoichiometry: BaO2+0.2 Ti+0.8 TiO2→BaTiO3+0.3 O2. An adiabatic temperature, Tad, of the reaction was calculated from known thermodynamic data to be 1917 °C. Real time chemical changes in the formation of BaTiO3 during the reaction have been monitored using time-resolved X-ray diffraction with synchrotron radiation as the X-ray source. A time resolution of 250 ms was achieved. The combustion synthesis of BaTiO3 was followed by observing the intensities of reactant and product Bragg diffraction peaks in order to qualitatively identify the phases present. Because BaTiO3 forms initially as a cubic phase, X-ray diffraction of the product was monitored for a period of 20 min after the reaction to observe the phase transformation to the tetragonal form. This transformation is evident in these post-reaction scans as the cubic 110 and 220 peaks are split to the tetragonal 101/110 and 202/220 ones, respectively.
The montane cloud-forests of the north-central Andes and the montane grassland and transitional elfin forest of the central Andean páramo contain a high diversity of bird species including several restricted range and uncommon species. Little is known of how densities of Andean cloud-forest species are affected by habitat degradation. Bird densities within pristine and degraded habitats at the Guandera Biological Reserve, Carchi province, Ecuador were recorded over a 10-week period. Densities were calculated for 48 species; where densities could be compared, 69% of species occurred at a higher density in pristine habitats. Pristine forest had the highest species richness with 72 species and páramo contained 44 species. In total, 26% of pristine forest species were only found in pristine forest, 39% of páramo species only in páramo, 13% of farmland species only in farmland and there were no exclusively secondary scrub species; 47% of species found in pristine forest, and 50% found in páramo were found in both secondary scrub and farmland. Restricted range species recorded at Guandera included the Carunculated Caracara Phalcobenus carunculatus, Black-thighed Puffleg Eriocnemis derbyi, Chestnut-bellied Cotinga Doliornis remseni, Crescent-faced Antpitta Grallaricula lineifrons, Masked Mountain-tanager Buthraupis wetmorei and Black-backed Bush-tanager Urothraupis stolzmanni. Three further species that occurred at Guandera of relatively local occurrence were the Grey-breasted Mountain Toucan Andigena hypoglauca, Golden-breasted Puffleg Eriocnemis mosquera and Mountain Avocetbill Opisthoprora euryptera. Of these nine species at least five used degraded habitats, while three occurred only in pristine treeline habitats.
A collaborative exercise, supervised by the World Health Organisation, was set up to compare ELISAs used for the serological detection of Salmonella enteritica serotype Enteritidis in chickens. The aim was to ascertain how far agreement could be reached on the interpretation of optical density readings for high titre, intermediate titre and low titre sera. Two sets of sera were sent to 14 participants. The first set compared high, medium and low titre sera raised in specified-pathogen-free and commercial broiler breeder chickens. The second set comprised 20 sera of different antibody titres raised in commercial birds reared under laboratory conditions and sent blind. Both indirect and double-antibody sandwich blocking ELISAs were used with a number of different detecting antigens. With a few exceptions good agreement was reached on the interpretation of results obtained from high and low titre sera from the optical density obtained with a single serum dilution. Differences were observed in the interpretation of medium titre sera. The results suggested that most ELISAs produce reasonably comparable results and that practical problems may arise from interpretation of the results mainly as a result of the choice of the criteria used for differentiating sera obtained from infected and uninfected chickens. These problems are discussed.
Detectable allelic variation at the Gpi-1 loci on the short arms of the homoeologous group 1 chromsomes in wheat is not common. However, a variant null allele at the Gpi-D1 locus is present in some stocks of Chinese Spring. This has allowed the locus to be mapped between the ω-gliadin locus carried distally on the short arm of chromosome 1D, Gli-D1 (34·5%) and the high-molecular-weight glutenin subunit locus carried near the centromere on the long arm, Glu-D1 (36·2%). The origin of this isoenzyme polymorphism in Chinese Spring stocks is described and its potential significance is discussed in relation to quantitative analysis of aneuploids, alien chromosome addition and substitution lines and intervarietal chromosome substitution lines involving Chinese Spring.
Recent work suggests that heavy use of cannabis is associated with an increased risk of schizophrenia-like psychosis. However, there is a dearth of experimental studies of the effects of the constituents of cannabis, such as Δ9-tetrahydrocannabinol (THC). In a study of intravenous (i.v.) synthetic THC in healthy humans, we aimed to study the relationship of the psychotic symptoms induced by THC to the consequent anxiety and neuropsychological impairment.
Twenty-two healthy adult males aged 28±6 years (mean±s.d.) participated in experimental sessions in which i.v. THC (2.5 mg) was administered under double-blind, placebo-controlled conditions. Self-rated and investigator-rated measurements of mood and psychosis [the University of Wales Institute of Science and Technology Mood Adjective Checklist (UMACL), the Positive and Negative Syndrome Scale (PANSS) and the Community Assessment of Psychic Experiences (CAPE)] were made at baseline and at 30, 80 and 120 min post-injection. Participants also completed a series of neuropsychological tests [the Rey Auditory Verbal Learning Task (RAVLT), Digit Span, Verbal Fluency and the Baddeley Reasoning Task] within 45 min of injection.
THC-induced positive psychotic symptoms, and participant- and investigator-rated measurements of these were highly correlated. Participants showed an increase in anxiety ratings but there was no relationship between either self- or investigator-rated positive psychotic symptoms and anxiety. THC also impaired neuropsychological performance but once again there was no relationship between THC-induced positive psychotic symptoms and deficits in working memory/executive function.
These findings confirm that THC can induce a transient, acute psychotic reaction in psychiatrically well individuals. The extent of the psychotic reaction was not related to the degree of anxiety or cognitive impairment.
Biological markers or ‘biomarkers’ of organ damage and dysfunction occupy a central position in the armamentarium of the clinician that is used for the screening, diagnosis and management of disease. Our knowledge of the pathophysiological basis of individual diseases continues to increase inexorably and the discoveries emanating from the Human Genome Project are set to enhance this knowledge immeasurably. Understanding the aetiopathogenesis of changes that take place in individual tissues, organs or compartments of the body can help in the search for markers that reflect these changes. Some of these changes may be directly related to the pathological abnormality while others might be a secondary consequence of the abnormality.
Basic research into the pathophysiology of a disease provides the foundation of knowledge that can lead to the discovery of valuable biomarkers. This foundation can also act as the starting point for the discovery of pharmaceutical interventions. Increasingly, with a more systematic approach to biomarker development and drug discovery, we are seeing the measurement of the biomarker playing a greater role in monitoring the efficacy and/or side effects of the therapeutic intervention. From a clinical standpoint, this can have a major benefit in assessing compliance with therapy, which is acknowledged to be one of the key determinants of efficacy, especially when there is no other ready means to judge the patient's response.
The discovery of a new biomarker is complemented by the development and validation of appropriate analytical technology.