Medical demography at stroke centers: Current situation in France.

INTRODUCTION: Following the 2010-2014 French national stroke action plan, the number of stroke center (SC) has gradually increased in France, allowing a homogeneous coverage and access to neurovascular care in organized and territorially defined structures. However, operational difficulties within SCs have been progressively reported over the last few years. The objective of this study was to identify the medical staff shortages in SC that may contribute to these difficulties. METHODS: A survey on the medical staffing level as of January 1, 2021 was sent to all French SC managers. Specific questions related on vacancies, need of interim medical staff, and participation in out-of-hour healthcare services. RESULTS: Among the 139 SC managers contacted, 122 (88%) filled in the questionnaire. Analysis of the data showed that over 879 physician positions opened, 163 (18.5%) remained vacant for a mean of two years, and that in 51 SCs (41.9%), more than two positions were unfilled. In 13 of these 51 SCs, the out-of-hour healthcare services relied on less than four practitioners, defining a critical situation, and three other SCs had to close temporarily (2) or permanently (1). Moreover, 39.2% of SCs with at least one vacancy used interim physicians, for a median period of 12.5 weeks/year (IQR 5-18). CONCLUSION: This study highlights the significant medical staff shortage in French SCs. In the absence of urgent measures, more SCs will close, jeopardizing the regional network and access to care for stroke patients.

Inequalities in energy drink consumption among UK adolescents: a mixed-methods study.

OBJECTIVE: To examine energy drink consumption among adolescents in the United Kingdom (UK) and associations with deprivation and dietary inequalities. DESIGN: Quantitative dietary and demographic data from the National Diet and Nutrition Survey (NDNS) repeated cross-sectional survey were analysed using logistic regression models. Qualitative data from semi-structured interviews were analysed using inductive thematic analysis. SETTING: UK. PARTICIPANTS: Quantitative data: nationally representative sample of 2587 adolescents aged 11-18 years. Qualitative data: 20 parents, 9 teachers, and 28 adolescents from Hampshire, UK. RESULTS: NDNS data showed adolescents' consumption of energy drinks was associated with poorer dietary quality (OR 0.46 per SD; 95% CI 0.37, 0.58; p<0.001). Adolescents from more deprived areas and lower income households were more likely to consume energy drinks than those in more affluent areas and households (OR 1.40; 95%CI 1.16, 1.69; p<0.001; OR 0.98 per £1000; 95%CI, 0.96, 0.99; p<0.001 respectively). Between 2008 and 2016, energy drink consumption among adolescents living in the most deprived areas increased, but decreased among those living in the most affluent neighbourhoods (p=0.04). Qualitative data identified three themes. First, many adolescents drink energy drinks because of their friends and because the unbranded drinks are cheap. Second, energy drink consumption clusters with other unhealthy eating behaviours and adolescents don't know why energy drinks are unhealthy. Third, adolescents believe voluntary bans in retail outlets and schools do not work. CONCLUSIONS: This study supports the introduction of age-dependent legal restrictions on the sale of energy drinks which may help curb existing socio-economic disparities in adolescents' energy drink intake.

Differential relationships between parent-child DXA and pQCT bone measures: Results from the Southampton Women's Survey.

AIM: To investigate the associations between indices of bone health in childhood and corresponding parental measures. METHODS: The Southampton Women's Survey characterised 12,583 non-pregnant women aged 20-34 years; 3158 subsequently had singleton live births. In a subset, dual-energy X-ray absorptiometry (DXA) measurements of bone area (BA), bone mineral content (BMC) and areal bone mineral density (aBMD) lumbar spine and total hip were obtained in the parent/offspring (aged 8-9 years) trios. Another subset of children (aged 6-7 years), and their parents, had peripheral quantitative computed tomography (pQCT; 4% and 38% tibia) measures. Using multivariable linear regression we examined relationships between mother/father and offspring, adjusting for parental age, habitual walking speed and education; offspring age and sex; and the corresponding bone measure in the other parent (ß-coefficients (95%CI) unit/unit for each bone measure). RESULTS: Data were available for 260 trios with DXA and 99 with pQCT. There were positive associations for BA, BMC and aBMD between either parent and offspring. Mother-child associations were of greater magnitude than father-child; for example, mother-child aBMD (ß = 0.26 g·cm-2/g·cm-2 (0.21,0.32)) and father-child aBMD (ß = 0.16 g·cm-2/g·cm-2 (0.11,0.21)), P-difference in ß = 0.007. In the subset with pQCT there was a positive association for mother-offspring 4% tibial total area (ß = 0.33 mm2/mm2 (0.17,0.48)), but little evidence of a father-offspring association (ß = -0.06 mm2/mm2 (-0.17,0.06)). In contrast offspring 38% cortical density was more strongly associated with this measure in fathers (ß = 0.48 mg·cm-3/mg·cm-3 (0.15,0.82)) than mothers (ß = 0.27 mg·cm-3/mg·cm-3 (-0.03,0.56)). In general mother-father differences were attenuated by adjustment for height. CONCLUSIONS: Whilst offspring bone measures are independently associated with those of either parent, the magnitude of the association is often greater for maternal than paternal relationships. These findings are consistent with an in utero influence on offspring growth but might also reflect genetic and/or epigenetic parent of origin effects. SUMMARY: In an established parent-offspring cohort, associations between parent and offspring bone indices were generally greater in magnitude for mother-offspring than father-offspring relationships.

Placental volume at 11 weeks is associated with offspring bone mass at birth and in later childhood: Findings from the Southampton Women's Survey.

OBJECTIVES: To investigate associations between placental volume (PV) at 11 weeks' gestation and offspring bone outcomes at birth, 6 years and 8 years. METHODS: 3D ultrasound scanning was used to assess 11 week PV in a subset (n = 236) of the Southampton Women's Survey (a prospective mother-offspring cohort). Maternal anthropometric measures and lifestyle information were obtained pre-pregnancy and at 11 weeks' gestation. Offspring dual-energy x-ray absorptiometry scanning was performed within 2 weeks postnatally and at 6 and 8 years. Linear regression was used to assess associations between PV and bone outcomes, adjusting for offspring age at DXA and sex, and maternal age, height, smoking status, walking speed and triceps skinfold thickness. ß are SD change in bone outcome per SD change in PV. RESULTS: In adjusted models, 11 week PV was positively associated with bone area (BA) at all time points, with evidence of persisting associations with increasing childhood age (birth: n = 80, ß = 0.23 [95%CI = 0.03, 0.42], 6 years: n = 110, ß = 0.17 [-0.01, 0.36], 8 years: n = 85, ß = 0.13 [-0.09, 0.36]). Similar associations between 11 week PV and bone mineral content (BMC) were observed. Associations with size-corrected bone mineral content were weaker at birth but strengthened in later childhood (birth: n = 78, ß = 0.07 [-0.21, 0.35], 6 years: n = 107, ß = 0.13 [-0.08, 0.34], 8 years: n = 71, ß = 0.19 [-0.05, 0.43]). CONCLUSIONS: 11 week PV is associated with DXA bone measures at birth, with evidence of persisting associations into later childhood. Further work is required to elucidate the contributions of placental morphology and function to gestational influences on skeletal development.

Outcomes of Acute Stroke Patients Requiring Mechanical Ventilation: Study Protocol for the SPICE Multicenter Prospective Observational Study.

BACKGROUND: Care pathways and long-term outcomes of acute stroke patients requiring mechanical ventilation have not been thoroughly studied. METHODS AND RESULTS: Stroke Prognosis in Intensive Care (SPICE) is a prospective multicenter cohort study which will be conducted in 34 intensive care units (ICUs) in the Paris, France area. Patients will be eligible if they meet all of the following inclusion criteria: (1) age of 18 years or older; (2) acute stroke (i.e., ischemic stroke, intracranial hemorrhage, or subarachnoid hemorrhage) diagnosed on neuroimaging; (3) ICU admission within 7 days before or after stroke onset; and (4) need for mechanical ventilation for a duration of at least 24 h. Patients will be excluded if they meet any of the following: (1) stroke of traumatic origin; (2) refusal to participate; and (3) privation of liberty by administrative or judicial decision. The primary endpoint is poor functional outcome at 1 year, defined by a score of 4 to 6 on the modified Rankin scale (mRS), indicating severe disability or death. Main secondary endpoints will include decisions to withhold or withdraw care, mRS scores at 3 and 6 months, and health-related quality of life at 1 year. CONCLUSIONS: The SPICE multicenter study will investigate 1-year outcomes, ethical issues, as well as care pathways of acute stroke patients requiring invasive ventilation in the ICU. Gathered data will delineate human resources and facilities needs for adequate management. The identification of prognostic factors at the acute phase will help to identify patients who may benefit from prolonged intensive care and rehabilitation. TRIAL REGISTRATION: NCT03335995.

Impact of maternal body mass index and gestational weight gain on pregnancy complications: an individual participant data meta-analysis of European, North American and Australian cohorts.

OBJECTIVE: To assess the separate and combined associations of maternal pre-pregnancy body mass index (BMI) and gestational weight gain with the risks of pregnancy complications and their population impact. DESIGN: Individual participant data meta-analysis of 39 cohorts. SETTING: Europe, North America, and Oceania. POPULATION: 265 270 births. METHODS: Information on maternal pre-pregnancy BMI, gestational weight gain, and pregnancy complications was obtained. Multilevel binary logistic regression models were used. MAIN OUTCOME MEASURES: Gestational hypertension, pre-eclampsia, gestational diabetes, preterm birth, small and large for gestational age at birth. RESULTS: Higher maternal pre-pregnancy BMI and gestational weight gain were, across their full ranges, associated with higher risks of gestational hypertensive disorders, gestational diabetes, and large for gestational age at birth. Preterm birth risk was higher at lower and higher BMI and weight gain. Compared with normal weight mothers with medium gestational weight gain, obese mothers with high gestational weight gain had the highest risk of any pregnancy complication (odds ratio 2.51, 95% CI 2.31- 2.74). We estimated that 23.9% of any pregnancy complication was attributable to maternal overweight/obesity and 31.6% of large for gestational age infants was attributable to excessive gestational weight gain. CONCLUSIONS: Maternal pre-pregnancy BMI and gestational weight gain are, across their full ranges, associated with risks of pregnancy complications. Obese mothers with high gestational weight gain are at the highest risk of pregnancy complications. Promoting a healthy pre-pregnancy BMI and gestational weight gain may reduce the burden of pregnancy complications and ultimately the risk of maternal and neonatal morbidity. TWEETABLE ABSTRACT: Promoting a healthy body mass index and gestational weight gain might reduce the population burden of pregnancy complications.

Associations between maternal physical activity in early and late pregnancy and offspring birth size: remote federated individual level meta-analysis from eight cohort studies.

OBJECTIVE: Evidence on the impact of leisure time physical activity (LTPA) in pregnancy on birth size is inconsistent. We aimed to examine the association between LTPA during early and late pregnancy and newborn anthropometric outcomes. DESIGN: Individual level meta-analysis, which reduces heterogeneity across studies. SETTING: A consortium of eight population-based studies (seven European and one US) comprising 72 694 participants. METHODS: Generalised linear models with consistent inclusion of confounders (gestational age, sex, parity, maternal age, education, ethnicity, BMI, smoking, and alcohol intake) were used to test associations between self-reported LTPA at either early (8-18 weeks gestation) or late pregnancy (30+ weeks) and the outcomes. Results were pooled using random effects meta-analyses. MAIN OUTCOME MEASURES: Birth weight, large-for-gestational age (LGA), macrosomia, small-for-gestational age (SGA), % body fat, and ponderal index at birth. RESULTS: Late, but not early, gestation maternal moderate to vigorous physical activity (MVPA), vigorous activity, and LTPA energy expenditure were modestly inversely associated with BW, LGA, macrosomia, and ponderal index, without heterogeneity (all: I2  = 0%). For each extra hour/week of MVPA, RR for LGA and macrosomia were 0.97 (95% CI: 0.96, 0.98) and 0.96 (95% CI: 0.94, 0.98), respectively. Associations were only modestly reduced after additional adjustments for maternal BMI and gestational diabetes. No measure of LTPA was associated with risk for SGA. CONCLUSIONS: Physical activity in late, but not early, pregnancy is consistently associated with modestly lower risk of LGA and macrosomia, but not SGA. TWEETABLE ABSTRACT: In an individual participant meta-analysis, late pregnancy moderate to vigorous physical activity modestly reduced birth size outcomes.

Breech presentation is associated with lower bone mass and area: findings from the Southampton Women's Survey.

We compared bone outcomes in children with breech and cephalic presentation at delivery. Neonatal whole-body bone mineral content (BMC) and area were lower in children with breech presentation. At 4 years, no differences in whole-body or spine measures were found, but hip BMC and area were lower after breech presentation. INTRODUCTION: Breech presentation is associated with altered joint shape and hip dysplasias, but effects on bone mineral content (BMC), area (BA) and density (BMD) are unknown. METHODS: In the prospective Southampton Women's Survey mother-offspring cohort, whole-body bone outcomes were measured using dual-energy X-ray absorptiometry (DXA) in 1430 offspring, as neonates (mean age 6 days, n = 965, 39 with a breech presentation at birth) and/or at age 4.1 years (n = 999, 39 breech). Hip and spine bone outcomes were also measured at age 4 years. RESULTS: Neonates with breech presentation had 4.2 g lower whole-body BMC (95% CI -7.4 to - 0.9 g, P = 0.012) and 5.9 cm2 lower BA (- 10.8 to - 1.0 cm2, P = 0.019), but BMD was similar between groups (mean difference - 0.007, - 0.016 to 0.002 g/cm2, P = 0.146) adjusting for sex, maternal smoking, gestational diabetes, mode of delivery, social class, parity, ethnicity, age at scan, birthweight, gestational age and crown-heel length. There were no associations between breech presentation and whole-body outcomes at age 4 years, but, in similarly adjusted models, regional DXA (not available in infants) showed that breech presentation was associated with lower hip BMC (- 0.51, - 0.98 to - 0.04 g, P = 0.034) and BA (- 0.67, - 1.28 to - 0.07 cm2, P = 0.03) but not with BMD (- 0.009, - 0.029 to 0.012 g, P = 0.408), or spine outcomes. CONCLUSIONS: These results suggest that breech presentation is associated with lower neonatal whole-body BMC and BA, which may relate to altered prenatal loading in babies occupying a breech position; these differences did not persist into later childhood. Modest differences in 4-year hip BMC and BA require further investigation.

Imaging performance of a dedicated radiation transparent RF coil on a 1.0 Tesla inline MRI-linac.

This work describes the first imaging studies on a 1.0 Tesla inline MRI-Linac using a dedicated transmit/receive RF body coil that has been designed to be completely radio transparent and provide optimum imaging performance over a large patient opening. A series of experiments was performed on the MRI-Linac to investigate the performance and imaging characteristics of a new dedicated volumetric RF coil: (1) numerical electromagnetic simulations were used to measure transmit efficiency in two patient positions; (2) image quality metrics of signal-to-noise ratio (SNR), ghosting and uniformity were assessed in a large diameter phantom with no radiation beam; (3) radiation induced effects were investigated in both the raw data (k-space) and image sequences acquired with simultaneous irradiation; (4) radiation dose was measured with and without image acquisition; (5) RF heating was studied using an MR-compatible fluoroptic thermometer and; (6) the in vivo image quality and versatility of the coil was demonstrated in normal healthy subjects for both supine and standing positions. Daily phantom measurements demonstrated excellent imaging performance with stable SNR over a period of 3 months (42.6 ± 0.9). Simultaneous irradiation produced no statistical change in image quality (p > 0.74) and no interference in raw data for a 20 × 20 cm radiation field. The coil was found to be efficient over large volumes and negligible RF heating was observed. Volunteer scans acquired in both supine and standing positions provided artefact free images with good anatomical visualisation. The first completely radio transparent RF coil for use on a 1.0 Tesla MRI-Linac has been described. There is no impact on either the imaging or dosimetry performance with a simultaneous radiation beam. The open design enables imaging and radiotherapy guidance in a variety of positons.

Development of a Short Questionnaire to Assess Diet Quality among Older Community-Dwelling Adults.

OBJECTIVE: To evaluate the use of a short questionnaire to assess diet quality in older adults. DESIGN: Cross-sectional study. SETTING: Hertfordshire, UK. PARTICIPANTS: 3217 community-dwelling older adults (59-73 years). MEASUREMENTS: Diet was assessed using an administered food frequency questionnaire (FFQ); two measures of diet quality were defined by calculating participants' 'prudent diet' scores, firstly from a principal component analysis of the data from the full FFQ (129 items) and, secondly, from a short version of the FFQ (including 24 indicator foods). Scores calculated from the full and short FFQ were compared with nutrient intake and blood concentrations of vitamin C and lipids. RESULTS: Prudent diet scores calculated from the full FFQ and short FFQ were highly correlated (0.912 in men, 0.904 in women). The pattern of associations between nutrient intake (full FFQ) and diet scores calculated using the short and full FFQs were very similar, both for men and women. Prudent diet scores calculated from the full and short FFQs also showed comparable patterns of association with blood measurements: in men and women, both scores were positively associated with plasma vitamin C concentration and serum HDL; in women, an inverse association with serum triglycerides was also observed. CONCLUSIONS: A short food-based questionnaire provides useful information about the diet quality of older adults. This simple tool does not require nutrient analysis, and has the potential to be of value to non-specialist researchers.

Modifiable risk factors of maternal postpartum weight retention: an analysis of their combined impact and potential opportunities for prevention.

BACKGROUND/OBJECTIVES: Pregnancy triggers a physiological change in weight status. Postpartum weight retention in the childbearing years can substantially alter a woman's weight gain trajectory, with several potential contributing factors identified. Most research has relied on women's recall of pre-pregnancy weight during pregnancy or later, and not considered risk factors in combination. Using measured pre-pregnancy weight, this study aimed to examine the associations of maternal postpartum weight retention with parity, pre-pregnancy BMI, excessive gestational weight gain (GWG), maternal serum vitamin D concentration and dietary Glycaemic Index in early and late pregnancy, and breastfeeding duration, including analysis of the combined impact of potentially modifiable risk factors. SUBJECTS/METHODS: Prospective cohort study of 12 583 non-pregnant women aged 20-34 years in Southampton (UK) who were assessed prior to pregnancy, with those who subsequently became pregnant followed up in early and late gestation, and after delivery (n=2559 in the final sample). Linear regression models examined potential predictors of weight retention in adjusted individual and multivariate analyses, and as a risk factor score. RESULTS: Compared with pre-pregnancy weight, 73% of women retained some weight at 6 months postpartum (mean (s.d.): 3.5 (6.2) kg). In the adjusted multivariate model, women who were primiparous, had a lower pre-pregnancy BMI, excessive GWG, a lower early pregnancy vitamin D concentration and breastfed for <6 months had greater weight retention 6 months postpartum (P<0.05 for all variables). For each additional modifiable risk factor (excessive GWG, low vitamin D concentration in early pregnancy and short breastfeeding duration; scale 0-3), women retained an additional 2.49 kg (95% CI: 2.16, 2.82; P<0.001). CONCLUSIONS: Having a greater number of modifiable risk factors was associated with greater weight retention 6 months postpartum. Initiatives supporting women to target these risk factors in the years prior to, during and after pregnancy could impact on their weight gain trajectory and later risk of adverse weight-related outcomes.

Maternal stress and psychological distress preconception: association with offspring atopic eczema at age 12 months.

BACKGROUND: Perinatal maternal stress and low mood have been linked to offspring atopic eczema. OBJECTIVES: To examine the relation of maternal stress/mood with atopic eczema in the offspring, focusing particularly on stress/psychological distress preconception. METHODS: At recruitment in the UK Southampton Women's Survey, preconception maternal reports of perceived stress in daily living and the effect of stress on health were recorded; in a subsample, psychological distress was assessed (12-item General Health Questionnaire). Infants were followed up at ages 6 (n = 2956) and 12 (n = 2872) months and atopic eczema ascertained (based on UK Working Party Criteria for the Definition of Atopic Dermatitis). At 6 months post-partum, mothers were asked if they had experienced symptoms of low mood since childbirth and completed the Edinburgh Postnatal Depression Scale. RESULTS: Preconception perceived stress affecting health [OR 1.21 (95% CI 1.08-1.35), P = 0.001] and stress in daily living [OR 1.16 (1.03-1.30), P = 0.014] were associated with an increased risk of offspring atopic eczema at age 12 months but not at 6 months, robust to adjustment for potentially confounding variables. Findings were similar for maternal psychological distress preconception. Low maternal mood between delivery and 6 months post-partum was associated with an increased risk of infantile atopic eczema at age 12 months, but no significant association between post-natal mood and atopic eczema was seen after taking account of preconception stress. CONCLUSION AND CLINICAL RELEVANCE: Our data provide novel evidence linking maternal stress at preconception to atopic eczema risk, supporting a developmental contribution to the aetiology of atopic eczema and pointing to potentially modifiable influences.

Automatic segmentation of the glenohumeral cartilages from magnetic resonance images.

PURPOSE: Magnetic resonance (MR) imaging plays a key role in investigating early degenerative disorders and traumatic injuries of the glenohumeral cartilages. Subtle morphometric and biochemical changes of potential relevance to clinical diagnosis, treatment planning, and evaluation can be assessed from measurements derived from in vivo MR segmentation of the cartilages. However, segmentation of the glenohumeral cartilages, using approaches spanning manual to automated methods, is technically challenging, due to their thin, curved structure and overlapping intensities of surrounding tissues. Automatic segmentation of the glenohumeral cartilages from MR imaging is not at the same level compared to the weight-bearing knee and hip joint cartilages despite the potential applications with respect to clinical investigation of shoulder disorders. In this work, the authors present a fully automated segmentation method for the glenohumeral cartilages using MR images of healthy shoulders. METHODS: The method involves automated segmentation of the humerus and scapula bones using 3D active shape models, the extraction of the expected bone-cartilage interface, and cartilage segmentation using a graph-based method. The cartilage segmentation uses localization, patient specific tissue estimation, and a model of the cartilage thickness variation. The accuracy of this method was experimentally validated using a leave-one-out scheme on a database of MR images acquired from 44 asymptomatic subjects with a true fast imaging with steady state precession sequence on a 3 T scanner (Siemens Trio) using a dedicated shoulder coil. The automated results were compared to manual segmentations from two experts (an experienced radiographer and an experienced musculoskeletal anatomist) using the Dice similarity coefficient (DSC) and mean absolute surface distance (MASD) metrics. RESULTS: Accurate and precise bone segmentations were achieved with mean DSC of 0.98 and 0.93 for the humeral head and glenoid fossa, respectively. Mean DSC scores of 0.74 and 0.72 were obtained for the humeral and glenoid cartilage volumes, respectively. The manual interobserver reliability evaluated by DSC was 0.80 ± 0.03 and 0.76 ± 0.04 for the two cartilages, implying that the automated results were within an acceptable 10% difference. The MASD between the automatic and the corresponding manual cartilage segmentations was less than 0.4 mm (previous studies reported mean cartilage thickness of 1.3 mm). CONCLUSIONS: This work shows the feasibility of volumetric segmentation and separation of the glenohumeral cartilages from MR images. To their knowledge, this is the first fully automated algorithm for volumetric segmentation of the individual glenohumeral cartilages from MR images. The approach was validated against manual segmentations from experienced analysts. In future work, the approach will be validated on imaging datasets acquired with various MR contrasts in patients.

Technical Note: Experimental results from a prototype high-field inline MRI-linac.

PURPOSE: The pursuit of real-time image guided radiotherapy using optimal tissue contrast has seen the development of several hybrid magnetic resonance imaging (MRI)-treatment systems, high field and low field, and inline and perpendicular configurations. As part of a new MRI-linac program, an MRI scanner was integrated with a linear accelerator to enable investigations of a coupled inline MRI-linac system. This work describes results from a prototype experimental system to demonstrate the feasibility of a high field inline MR-linac. METHODS: The magnet is a 1.5 T MRI system (Sonata, Siemens Healthcare) was located in a purpose built radiofrequency (RF) cage enabling shielding from and close proximity to a linear accelerator with inline (and future perpendicular) orientation. A portable linear accelerator (Linatron, Varian) was installed together with a multileaf collimator (Millennium, Varian) to provide dynamic field collimation and the whole assembly built onto a stainless-steel rail system. A series of MRI-linac experiments was performed to investigate (1) image quality with beam on measured using a macropodine (kangaroo) ex vivo phantom; (2) the noise as a function of beam state measured using a 6-channel surface coil array; and (3) electron contamination effects measured using Gafchromic film and an electronic portal imaging device (EPID). RESULTS: (1) Image quality was unaffected by the radiation beam with the macropodine phantom image with the beam on being almost identical to the image with the beam off. (2) Noise measured with a surface RF coil produced a 25% elevation of background intensity when the radiation beam was on. (3) Film and EPID measurements demonstrated electron focusing occurring along the centerline of the magnet axis. CONCLUSIONS: A proof-of-concept high-field MRI-linac has been built and experimentally characterized. This system has allowed us to establish the efficacy of a high field inline MRI-linac and study a number of the technical challenges and solutions.

Higher maternal serum concentrations of nicotinamide and related metabolites in late pregnancy are associated with a lower risk of offspring atopic eczema at age 12 months.

BACKGROUND: Evidence that atopic eczema partly originates in utero is increasing, with some studies linking the risk of developing the condition with aspects of maternal diet during pregnancy. Nicotinamide, a naturally occurring nutrient that is maintained through the dietary intakes of vitamin B3 and tryptophan, has been used in the treatment of some skin conditions including atopic eczema. OBJECTIVE: To examine the relation of maternal serum concentrations of nicotinamide and related tryptophan metabolites to the risk of atopic eczema in the offspring. METHODS: Within the UK Southampton Women Survey, infantile atopic eczema at ages 6 and 12 months was ascertained (modified UK Working Party Criteria for the Definition of Atopic Dermatitis). Maternal serum levels of kynurenine, kynurenic acid, anthranilic acid, tryptophan, nicotinamide and N1-methylnicotinamide were measured in late pregnancy by mass spectrometry (n = 497) and related to the odds ratio of infantile atopic eczema. RESULTS: Maternal nicotinamide and related metabolite concentrations were not associated with offspring atopic eczema at age 6 months. Higher concentrations of nicotinamide and anthranilic acid were, however, associated with a lower risk of eczema at age 12 months (odds ratios 0.69, 95% CI 0.53-0.91/SD change, P = 0.007 and 0.63, 0.48-0.83, P = 0.001, respectively). The associations were robust to adjustment for potentially confounding variables. CONCLUSION AND CLINICAL RELEVANCE: This is the first study linking maternal serum concentrations of nicotinamide and related metabolites to the risk of atopic eczema in the offspring. The findings point to potentially modifiable maternal influences on this complex and highly prevalent condition.

Posterior reversible encephalopathy syndrome (PRES) and hypomagnesemia: A frequent association?

Posterior reversible encephalopathy syndrome (PRES) is a serious neurological condition encountered in various medical fields. Pathophysiological factor(s) common to PRES cases of apparently unrelated etiologies are yet to be found. Based on the hypothesis that hypomagnesemia might participate in the cascade leading to PRES, our study sought to verify whether hypomagnesemia is frequently associated with PRES regardless of etiology. From a retrospective study of a cohort of 57 patients presenting with PRES of different etiologies, presented here are the findings of 19 patients with available serum magnesium levels (SMLs) during PRES. In the acute phase of PRES, hypomagnesemia was present in all 19 patients in spite of differences in etiology (including immunosuppressive drugs, hypertensive encephalopathy, eclampsia, systemic lupus erythematosus, iatrogenic etiology and unknown). SMLs were within normal ranges prior to PRES and below normal ranges during the first 48h of PRES, with a significant decrease in SMLs during the acute phase. In this retrospective study, constant hypomagnesemia was observed during the acute phase of PRES regardless of its etiology. These results now require larger studies to assess the particular importance of acute hypomagnesemia in PRES and especially the possible need to treat PRES with magnesium sulfate.

Age at introduction of solid foods and feeding difficulties in childhood: findings from the Southampton Women's Survey.

This study aimed to determine whether age at introduction of solid foods was associated with feeding difficulties at 3 years of age. The present study was carried out using data from the Southampton Women's Survey (SWS). Women enrolled in the SWS who subsequently became pregnant were followed-up during pregnancy and postpartum, and the offspring have been studied through childhood. Maternal socio-demographic and anthropometric data and child anthropometric and feeding data were collected through interviews and self-administered questionnaires. When the children were 3 years of age, mothers/carers rated six potential child feeding difficulty questions on a four-point Likert scale, including one general question and five specific feeding difficulty questions. Age at introduction of solids as a predictor of feeding difficulties was examined in 2389 mother-child pairs, adjusting for child (age last breast fed, sex, gestation) and maternal characteristics (parity, pre-pregnancy BMI, age, education, employment, parenting difficulties, diet quality). The majority of mothers/carers (61 %) reported some feeding difficulties (general feeding difficulty question) at 3 years of age, specifically with their child eating enough food (61 %), eating the right food (66 %) and being choosy with food (74 %). Children who were introduced to solids ≥6 months had a lower risk of feeding difficulties (RR 0·73; 95 % CI 0·59, 0·91, P=0·004) than children who were introduced to solids between 4 and 6 months. No other significant associations were found. There were few associations between feeding difficulties in relation to age at introduction of solid foods. However, general feeding difficulties were less common among infants introduced to solid foods ≥6 months of age.

Design and Experimental Evaluation of a Non-Invasive Microwave Head Imaging System for Intracranial Haemorrhage Detection.

An intracranial haemorrhage is a life threatening medical emergency, yet only a fraction of the patients receive treatment in time, primarily due to the transport delay in accessing diagnostic equipment in hospitals such as Magnetic Resonance Imaging or Computed Tomography. A mono-static microwave head imaging system that can be carried in an ambulance for the detection and localization of intracranial haemorrhage is presented. The system employs a single ultra-wideband antenna as sensing element to transmit signals in low microwave frequencies towards the head and capture backscattered signals. The compact and low-profile antenna provides stable directional radiation patterns over the operating bandwidth in both near and far-fields. Numerical analysis of the head imaging system with a realistic head model in various situations is performed to realize the scattering mechanism of haemorrhage. A modified delay-and-summation back-projection algorithm, which includes effects of surface waves and a distance-dependent effective permittivity model, is proposed for signal and image post-processing. The efficacy of the automated head imaging system is evaluated using a 3D-printed human head phantom with frequency dispersive dielectric properties including emulated haemorrhages with different sizes located at different depths. Scattered signals are acquired with a compact transceiver in a mono-static circular scanning profile. The reconstructed images demonstrate that the system is capable of detecting haemorrhages as small as 1 cm3. While quantitative analyses reveal that the quality of images gradually degrades with the increase of the haemorrhage's depth due to the reduction of signal penetration inside the head; rigorous statistical analysis suggests that substantial improvement in image quality can be obtained by increasing the data samples collected around the head. The proposed head imaging prototype along with the processing algorithm demonstrates its feasibility for potential use in ambulances as an effective and low cost diagnostic tool to assure timely triaging of intracranial hemorrhage patients.

Relation of FTO gene variants to fetal growth trajectories: Findings from the Southampton Women's survey.

INTRODUCTION: Placental function is an important determinant of fetal growth, and fetal growth influences obesity risk in childhood and adult life. Here we investigated how FTO and MC4R gene variants linked with obesity relate to patterns of fetal growth and to placental FTO expression. METHODS: Southampton Women's Survey children (n = 1990) with measurements of fetal growth from 11 to 34 weeks gestation were genotyped for common gene variants in FTO (rs9939609, rs1421085) and MC4R (rs17782313). Linear mixed-effect models were used to analyse relations of gene variants with fetal growth. RESULTS: Fetuses with the rs9939609 A:A FTO genotype had faster biparietal diameter and head circumference growth velocities between 11 and 34 weeks gestation (by 0.012 (95% CI 0.005 to 0.019) and 0.008 (0.002-0.015) standard deviations per week, respectively) compared to fetuses with the T:T FTO genotype; abdominal circumference growth velocity did not differ between genotypes. FTO genotype was not associated with placental FTO expression, but higher placental FTO expression was independently associated with larger fetal size and higher placental ASCT2, EAAT2 and y + LAT2 amino acid transporter expression. Findings were similar for FTO rs1421085, and the MC4R gene variant was associated with the fetal growth velocity of head circumference. DISCUSSION: FTO gene variants are known to associate with obesity but this is the first time that the risk alleles and placental FTO expression have been linked with fetal growth trajectories. The lack of an association between FTO genotype and placental FTO expression adds to emerging evidence of complex biology underlying the association between FTO genotype and obesity.

Triage practices in stroke units: Physicians' perceptions and ethical issues.

OBJECTIVE: We aimed to explore acute stroke admission decisions and to discuss ethical issues in triage practices in stroke units (SUs) in France. METHODS: In this study, 337 questionnaires were sent to physicians involved in acute admission to SUs in Île-de-France (neurologists and physicians from emergency medical services). The questionnaires comprised questions about physicians' perceptions of the reasonable allocation of SU beds and admission criteria for patients in SU in clinical vignettes illustrating complex situations. RESULTS: In total, 162 questionnaires were fully completed. There were some discrepancies in perceptions and reporting practices between emergency physicians and neurologists concerning patient admission criteria. Triage choices were more frequently declared by emergency physicians than by neurologists and were related to the difficulty of obtaining a positive response for the admission of certain complex patients (particularly those with comorbidities). CONCLUSIONS: Despite recommendations stating that all patients with stroke should be admitted to SUs, this study has shown that triage practices exist in stroke admission decisions. The triage depends on the role and perceptions of each physician in acute stroke management. These decisions suggest reflections on the applicability of distributive justice theories and on ethical issues in triage practices in medicine.