Including endophenotypes as covariates in variance component heritability and linkage analysis

The purpose of these analyses was to determine if incorporating or adjusting for covariates in genetic analyses helped or hindered in genetic analyses, specifically heritability and linkage analyses. To study this question, two types of covariate models were used in the simulated Genetic Analysis Workshop 14 dataset in which the true gene locations are known. All four populations of one replicate were combined for the analyses. The first model included typical covariates of sex and cohort (population) and the second included the typical covariates and also those related endophenotypes that are thought to be associated with the trait (phenotypes A, B, C, D, E, F, G, H, I, J, K, and L). A final best fit model produced in the heritability analyses was used for linkage. Linkage for disease genes D1, D3, and D4 were localized using models with and without the covariates. The use of inclusion of covariates did not appear to have any consistent advantage or disadvantage for the different phenotypes in regards to gene localization or false positive rate

Effects of breaking up prolonged sitting following low and high glycaemic index breakfast consumption on glucose and insulin concentrations

Purpose: Breaking up prolonged sitting can attenuate the postprandial rise in glucose and insulin. Whether such effects are dependent of the glycaemic index (GI) of the consumed carbohydrate is unknown. This study examined the acute effects of breaking up prolonged sitting following a low GI and a high GI breakfast on postprandial glucose and insulin concentrations. Procedures: Fourteen adult males aged 22.1 ± 1.2 years completed four, 4 h experimental conditions: high GI breakfast followed by uninterrupted sitting (HGI-SIT), low GI breakfast followed by uninterrupted sitting (LGI-SIT), high GI breakfast followed by 2 min activity breaks every 20 min (HGI-ACT), and low GI breakfast followed by 2 min activity breaks every 20 min (LGI-ACT). Positive incremental area under the curve (iAUC) for glucose and insulin (mean [95% CI]) for each 4h experimental condition was calculated. Statistical analyses were completed using linear mixed models. Results: The sitting × breakfast GI interaction was not significant for glucose positive iAUC (P=0.119). Glucose positive iAUC (mmol/L4 h−1) was significantly lower in the activity breaks conditions than the uninterrupted sitting conditions (2.07 [2.24, 2.89] vs. 2.56 [1.74, 2.40], respectively, P=0.004) and significantly lower in the low GI conditions than the high GI conditions (2.13 [1.80, 2.45] vs. 2.51 [2.18, 2.84], respectively, P=0.022). Insulin concentrations did not differ between conditions (P ≥ 0.203). Conclusions: Breaking up prolonged sitting and lowering breakfast GI independently reduced postprandial glucose responses. This indicates that interrupting prolonged sitting and reducing dietary GI are beneficial approaches for reducing cardiometabolic disease risk

Factors affecting contraceptive choice in women over 40: a qualitative study

Objective To explore the views of women over 40 years in choosing and using contraception, and to inform how contraceptive counselling for this age group could be improved. Design, setting and participants Fourteen women aged 40–52 years were recruited through social media platforms to take part in online, semistructured, in-depth interviews. Transcripts were analysed using a qualitative thematic approach. Results (1) Participants were anxious about unplanned pregnancy, and still highly motivated to avoid this. (2) Changes of contraceptive method over the lifecourse were occasionally precipitated by emergent health conditions, but healthcare providers often recommended a change in method on the basis of age alone. (3) Participants were experiencing perimenopausal symptoms but were largely unaware of how hormonal contraception could be used to treat these symptoms. (4) Prior negative experiences with contraceptive methods, coercive experiences with healthcare providers, and traumatic life events all contributed to a narrowing of contraceptive preference in later life. Conclusion Women over 40 years may be highly motivated to avoid pregnancy. This age group may have complex contraceptive histories with emerging perimenopausal symptoms. Women over 40 years may have accumulated adverse experiences which impact their contraceptive choices. These factors need to be explored by clinicians, to facilitate shared decision-making

Dynamic Light Regulation of Translation Status in Arabidopsis thaliana

Light, a dynamic environmental parameter, is an essential regulator of plant growth and development. Light-regulated transcriptional networks are well documented, whereas light-regulated post-transcriptional regulation has received limited attention. In this study, dynamics in translation of cytosolic mRNAs were evaluated at the genome-level in Arabidopsis thaliana seedlings grown under a typical light/dark diurnal regime, shifted to darkness at midday, and then re-illuminated. One-hour of unanticipated darkness reduced levels of polysomes by 17% in a manner consistent with inhibition of initiation of translation. This down-regulation of translation was reversed within 10 min of re-illumination. Quantitative comparison of the total cellular population of transcripts (the transcriptome) to those associated with one or more 80S ribosome (the translatome) identified over 1600 mRNAs that were differentially translated in response to light availability. Unanticipated darkness limited both transcription and translation of mRNAs encoding components of the photosynthetic machinery. Many mRNAs encoding proteins associated with the energy demanding process of protein synthesis were stable but sequestered in the dark, in a rapidly reversible manner. A meta-analysis determined these same transcripts were similarly and coordinately regulated in response to changes in oxygen availability. The dark and hypoxia translationally repressed mRNAs lack highly supported candidate RNA-regulatory elements but are characterized by G + C-rich 5′-untranslated regions. We propose that modulation of translation of a subset of cellular mRNAs functions as an energy conservation mechanism

Design and analysis of laboratory experiments on aquatic plant litter decomposition

Microcosm studies are a useful tool when it comes to studying leaf litter decomposition but designing and analysing them can be a tricky path with many pitfalls. Because there is a plethora of drivers of leaf decomposition, it is important to be precise about the scientific questions that can be addressed with microcosm set-ups, and to use experimental designs that have minimal logistic implications but, at the same time, high statistical power. In this chapter, we first set the scene by introducing a hypothetical study that has the aim to estimate how leaf decomposition is driven by different decomposers and abiotic conditions. Following on from this scenario, we give an overview of the main biotic and abiotic drivers of leaf decomposition that will play a role in laboratory settings (with special attention to consumer species identity, species richness, body size and metabolic capacity, and also temperature, time scales and stressors). We then explain how to design and analyse laboratory experiments on aquatic leaf litter decomposition including the mathematics for calculating the metabolic power of leaf decomposers and some statistical models. Further three case studies are given—highly controlled experiments that can be analysed by analysis of variance.PostprintPeer reviewe

Relationships and Sex Education teaching in English secondary schools and the impact of the COVID-19 pandemic

The impact of the COVID-19 pandemic on school education resulted in class disruption and fragmented online teaching. Relationships and Sex Education (RSE) was made compulsory in England in 2020, but the impact of the COVID-19 pandemic on RSE is unclear. In this study, 16 teachers working in English secondary schools participated in online qualitative, semi-structured interviews on their experiences teaching RSE. Themes were identified using deductive and inductive codes as part of a thematic analysis process. Participants taught children aged 11–18 in independent, comprehensive and academy schools. Teachers found it difficult to deliver high quality RSE lessons because of concern that available material would be inappropriate for virtual delivery. Fragmentation of teaching also limited the development of pupil-teacher rapport, highlighted as key to effective RSE. Extra-curricular initiatives were also disrupted by the pandemic, persisting even after face-to-face teaching returned as schools focused on ‘core’ academic subjects. RSE teaching was seriously impacted by the COVID-19 pandemic, and although face to face teaching has resumed, healthy peer-on-peer relationships remain impacted by fragmented teaching. Ongoing prioritisation of RSE, and the appropriate use of digital resources, will support young people moving forward and help prepare for any future disruption of to face-to-face teaching

Reduced axonal diameter of peripheral nerve fibres in a mouse model of Rett syndrome

Rett syndrome (RTT) is a neurological disorder characterized by motor and cognitive impairment, autonomic dysfunction and a loss of purposeful hand skills. In the majority of cases, typical RTT is caused by de novo mutations in the X-linked gene, MECP2. Alterations in the structure and function of neurons within the central nervous system of RTT patients and Mecp2-null mouse models are well established. In contrast, few studies have investigated the effects of MeCP2-deficiency on peripheral nerves. In this study, we conducted detailed morphometric as well as functional analysis of the sciatic nerves of symptomatic adult female Mecp2+/- mice. We observed a significant reduction in the mean diameter of myelinated nerve fibers in Mecp2+/- mice. In myelinated fibers, mitochondrial densities per unit area of axoplasm were significantly altered in Mecp2+/- mice. However, conduction properties of the sciatic nerve of Mecp2 knockout mice were not different from control. These subtle changes in myelinated peripheral nerve fibers in heterozygous Mecp2 knockout mice could potentially explain some RTT phenotypes

Views, attitudes and experiences of South Asian women concerning sexual health services in the UK: a qualitative study

OBJECTIVE: To explore the views, attitudes, and experiences of South Asian women in the UK regarding sexual health services. METHODS: We performed virtual semi-structured interviews with South Asian women 18 and over living in the UK. We explored participants' experiences of accessing sexual health services, including contraception, smear tests and sexually transmitted infection (STI) tests. We coded interview transcripts and analysed them thematically. RESULTS: From February to April 2021, we conducted 14 interviews with South Asian women between the ages of 18 and 40 living in England and Wales, from February to April 2021. We identified four overarching themes: Access to sexual health services, entry to sexual health services, quality of sexual health services and stigma associated with sexual health services. Important barriers to sexual health services include limited knowledge of local provision, stigma and shame, and concerns about confidentiality. Participants found it difficult to discuss their sexual health (with anyone) and were often being met with judgement and a lack of partnership from clinicians. CONCLUSION: Our results suggest that South Asian women are uncomfortable accessing sexual health services and communicating their sexual health concerns with health care professionals. Service providers should collaborate with community-based organisations to ensure that services are discrete, confidential, and culturally appropriate