Gene × environment interactions in schizophrenia: evidence from genetic mouse models

The study of gene × environment, as well as epistatic interactions in schizophrenia, has provided important insight into the complex etiopathologic basis of schizophrenia. It has also increased our understanding of the role of susceptibility genes in the disorder and is an important consideration as we seek to translate genetic advances into novel antipsychotic treatment targets. This review summarises data arising from research involving the modelling of gene × environment interactions in schizophrenia using preclinical genetic models. Evidence for synergistic effects on the expression of schizophrenia-relevant endophenotypes will be discussed. It is proposed that valid and multifactorial preclinical models are important tools for identifying critical areas, as well as underlying mechanisms, of convergence of genetic and environmental risk factors, and their interaction in schizophrenia

Design and validation of a German version of the GSRS-IBS - an analysis of its psychometric quality and factorial structure

Background: Currently, a suitable questionnaire in German language is not available to monitor the progression and evaluate the severity of irritable bowel syndrome (IBS). Therefore, this study aimed to translate the Gastrointestinal Symptom Rating Scale for Irritable Bowel Syndrome (GSRS-IBS) into German and to evaluate its psychometric qualities and factorial structure. Methods: This study is based on a total sample of 372 participants [62.6% female, mean age = 41 years (SD = 17 years)]. 17.5% of the participants had a diagnosis of IBS, 19.9% were receiving treatment for chronic inflammatory bowel disease, 12.1% of the participants were recruited from a psychosomatic clinic, and 50.5% belonged to a control group. All participants completed the German version of GSRS-IBS (called Reizdarm-Fragebogen, RDF), as well as the Gießen Subjective Complaints List (GBB-24) and the Hospital Anxiety and Depression Scale - German version (HADS-D). Results: The internal consistency of the RDF total scale was at least satisfactory in all subsamples (Cronbach’s Alpha between .77 and .92), and for all subscales (Cronbach’s Alpha between .79 and .91). The item difficulties (between .25 and .73) and the item-total correlations (between .48 and .83) were equally satisfactory. Principal axis analysis revealed a four-factorial structure of the RDF items, which mainly resembled the structure of the English original. Convergent validity was established based on substantial and significant correlations with the stomach-complaint scale of the GBB-24 (r = .71; p < .01) and the anxiety (r = .42; p < .01) and depression scales (r = .43; p < .01) of the HADS-D. Conclusion: The German version of the GSRS-IBS RDF proves to be an effective, reliable, and valid questionnaire for the assessment of symptom severity in IBS, which can be used in clinical practice as well as in clinical studies

An Exhaustive Symmetry Approach to Structure Determination: Phase Transitions in Bi2Sn2O7

The exploitable properties of many materials are intimately linked to symmetry-lowering structural phase transitions. We present an automated and exhaustive symmetry-mode method for systematically exploring and solving such structures which will be widely applicable to a range of functional materials. We exemplify the method with an investigation of the Bi2Sn2O7 pyrochlore, which has been shown to undergo transitions from a parent γ cubic phase to β and α structures on cooling. The results include the first reliable structural model for β-Bi2Sn2O7 (orthorhombic Aba2, a = 7.571833(8), b = 21.41262(2), and c = 15.132459(14) Å) and a much simpler description of α-Bi2Sn2O7 (monoclinic Cc, a = 13.15493(6), b = 7.54118(4), and c = 15.07672(7) Å, β = 125.0120(3)°) than has been presented previously. We use the symmetry-mode basis to describe the phase transition in terms of coupled rotations of the Bi2O′ anti-cristobalite framework, which allow Bi atoms to adopt low-symmetry coordination environments favored by lone-pair cations

Is there a renoprotective value to leukodepletion during heart valve surgery? A randomized controlled trial (ROLO)

Background: Acute Kidney Injury (AKI) adversely affects outcomes after cardiac surgery. A major mediator of AKI is the activation of leukocytes through exposure to the cardiopulmonary bypass circuit. We evaluate the use of leukodepletion filters throughout bypass to protect against post-operative AKI by removing activated leukocytes during cardiac surgery. Methods: This is a single-centre, double-blind, randomized controlled trial comparing the use of leukodepletion versus a standard arterial filter throughout bypass. Elective adult patients undergoing heart valve surgery with or without concomitant procedures were investigated. The primary clinical outcome measured was the development of AKI according to the KDIGO criteria. Secondary measures included biomarkers of renal tubular damage (urinary Retinol Binding Protein and Kidney Injury Molecule-1), glomerular kidney injury (urinary Micro Albumin and serum Cystatin C) and urinary Neutrophil Gelatinase Associated Lipocalin, as well as the length of hospital stay and quality of life measures through EQ-5D-5L questionnaires. Results: The ROLO trial randomized 64 participants with a rate of recruitment higher than anticipated (57% achieved, 40% anticipated). The incidence of AKI was greater in the leukodepletion filter group (44% versus 23%, risk difference 21, 95% CI − 2 to 44%). This clinical finding was supported by biomarker levels especially by a tendency toward glomerular insult at 48 h, demonstrated by a raised serum Cystatin C (mean difference 0.11, 95% CI 0.00 to 0.23, p = 0.068) in the leukodepleted group. There was however no clear association between the incidence or severity of AKI and length of hospital stay. On average, health related quality of life returned to pre-operative levels in both groups within 3 months of surgery. Conclusions: Leukocyte depletion during cardiopulmonary bypass does not significantly reduce the incidence of AKI after valvular heart surgery. Other methods to ameliorate renal dysfunction after cardiac surgery need to be investigated. Trial registration: The trial was registered by the International Standard Randomized Controlled Trial Number Registry ISRCTN42121335. Registered on the 18 February 2014. The trial was run by the Bristol Clinical Trials and Evaluation Unit. This trial was financially supported by the National Institute of Health Research (Research for Patient Benefit), award ID: PB-PG-0711-25,090

Barriers and enablers to guideline implementation strategies to improve obstetric care practice in low- and middle-income countries: a systematic review of qualitative evidence

Peer reviewedPublisher PD

Health amongst former rugby union players:A cross-sectional study of morbidity and health-related quality of life

Abstract In the general population, physical activity is associated with improved health outcomes. However, long-term sports participation may be associated with adverse outcomes, particularly at the elite level. The aims of this study were to assess morbidity and health-related quality of life (HrQoL) amongst former rugby players, compared to an age-standardised general population sample. A cross-sectional study of former elite, male, rugby players (n = 259) was undertaken, and standardised morbidity ratios (SMR) calculated, assessing morbidity prevalence relative to English Longitudinal Study of Aging participants (ELSA, n = 5186). HrQoL, measured using the EQ-5D, was compared to a Health Survey for England (HSE, n = 2981) sample. In SMR analyses of participants aged 50+, diabetes was significantly lower amongst former players, (0.28, 95% CI 0.11–0.66), whereas osteoarthritis (4.00, 95% CI 3.32–4.81), joint replacement (6.02, 95% CI 4.66–7.77), osteoporosis (2.69, 95% CI 1.35–5.38), and anxiety (2.00, 95% CI 1.11–3.61) were significantly higher. More problems in HrQoL were reported amongst former players within the domains of mobility (p < 0.001), self-care (p = 0.041), usual activities (p < 0.001) and pain/discomfort (p < 0.001). Morbidity and HrQoL differ between players and the general population, with higher musculoskeletal morbidity and lower diabetes amongst former players. The magnitude of musculoskeletal morbidity may warrant proactive osteoarthritis management within this population

Differential effects of mTOR inhibition and dietary ketosis in a mouse model of subacute necrotizing encephalomyelopathy

Genetic mitochondrial diseases are the most frequent cause of inherited metabolic disorders and one of the most prevalent causes of heritable neurological disease. Leigh syndrome is the most common clinical presentation of pediatric mitochondrial disease, typically appearing in the first few years of life, and involving severe multisystem pathologies. Clinical care for Leigh syndrome patients is difficult, complicated by the wide range of symptoms including characteristic progressive CNS lesion, metabolic sequelae, and epileptic seizures, which can be intractable to standard management. While no proven therapies yet exist for the underlying mitochondrial disease, a ketogenic diet has led to some reports of success in managing mitochondrial epilepsies, with ketosis reducing seizure risk and severity. The impact of ketosis on other aspects of disease progression in Leigh syndrome has not been studied, however, and a rigorous study of the impact of ketosis on seizures in mitochondrial disease is lacking. Conversely, preclinical efforts have identified the intracellular nutrient signaling regulator mTOR as a promising therapeutic target, with data suggesting the benefits are mediated by metabolic changes. mTOR inhibition alleviates epilepsies arising from defects in TSC, an mTOR regulator, but the therapeutic potential of mTOR inhibition in seizures related to primary mitochondrial dysfunction is unknown. Given that ketogenic diet is used clinically in the setting of mitochondrial disease, and mTOR inhibition is in clinical trials for intractable pediatric epilepsies of diverse causal origins, a direct experimental assessment of their effects is imperative. Here, we define the impact of dietary ketosis on survival and CNS disease in the Ndufs4(KO) mouse model of Leigh syndrome and the therapeutic potential of both dietary ketosis and mTOR inhibition on seizures in this model. These data provide timely insight into two important clinical interventions

Climate affects neighbour‐induced changes in leaf chemical defences and tree diversity‐herbivory relationships

1. Associational resistance theory predicts that insect herbivory decreases with increasing tree diversity in forest ecosystems. However, the generality of this effect and its underlying mechanisms are still debated, particularly since evidence has accumulated that climate may influence the direction and strength of the relationship between diversity and herbivory. 2. We quantified insect leaf herbivory and leaf chemical defences (phenolic compounds) of silver birch Betula pendula in pure and mixed plots with different tree species composition across 12 tree diversity experiments in different climates. We investigated whether the effects of neighbouring tree species diversity on insect herbivory in birch, that is, associational effects, were dependent on the climatic context, and whether neighbour-induced changes in birch chemical defences were involved in associational resistance to insect herbivory. 3. We showed that herbivory on birch decreased with tree species richness (i.e. associational resistance) in colder environments but that this relationship faded as mean annual temperature increased. 4. Birch leaf chemical defences increased with tree species richness but decreased with the phylogenetic distinctiveness of birch from its neighbours, particularly in warmer and more humid environments

Quantitative Factors Proposed to Influence the Prevalence of Canine Tick-Borne Disease Agents in the United States

The Companion Animal Parasite Council hosted a meeting to identify quantifiable factors that can influence the prevalence of tick-borne disease agents among dogs in North America. This report summarizes the approach used and the factors identified for further analysis with mathematical models of canine exposure to tick-borne pathogens