Oral Health as a Risk Factor for Alzheimer Disease.

In patients with Alzheimer's disease pathophysiological changes of the brain that initiate the onset of Alzheimer's disease include accumulation of amyloid-ß plaques and phosphorylation of tau-tangles. A rather recently considered risk factor for the onset of Alzheimer's disease is poor oral health. The aim of this systematic review of the literature was to assess the potential association(s) of oral health as a risk factor for the onset of Alzheimer's disease. After a systematic search of Pubmed, Embase and Web of Science. A total of 1962 studies were assessed, of which 17 studies demonstrated possible associations between oral health diseases and Alzheimer's disease. 4 theories could be distinguished that describe the possible links between oral health and the development or onset of Alzheimer's disease; 1) role of pathogens, 2) role of inflammatory mediators, 3) role of APOE alleles and 4) role of Aß peptide. The main common denominator of all the theories is the neuroinflammation due to poor oral health. Yet, there is insufficient evidence to prove a link due to the diversity of the designs used and the quality of the study design of the included studies. Therefore, further research is needed to find causal links between oral health and neuroinflammation that possibly can lead to the onset of Alzheimer's disease with the future intention to prevent cognitive decline by better dental care.

The vanishing of the ACoA syndrome after aneurysmal subarachnoid haemorrhage: New era, different management, fewer problems?

Historically, a specific set of symptoms has been related to the rupture and repair of anterior communicating artery (ACoA) aneurysms. These consequences were defined as the 'ACoA syndrome' and included observations of severe memory loss, confabulation and personality or behavioural changes. These observations correspond to neuropsychological impairments in memory, executive functions and social cognition. However, in more recent studies, the existence of such a distinct syndrome has been called into question. We aimed to investigate the existence of the ACoA syndrome, by combining analysis of our own data with a systematic review of the literature. Memory, executive functions and social cognition of subarachnoid haemorrhage patients with ACoA aneurysms (N = 28) were compared to patients with aneurysms in other locations (N = 66). Results showed no significant differences. Subsequently, a systematic review of the existing literature on the ACoA syndrome was performed using Embase and PubMed until October 2022. Studies that investigated cognitive functions after rupture and repair of ACoA aneurysms were included. The search yielded 847 unique entries and after screening titles and abstracts, 648 records were excluded. 199 full-text articles were assessed for eligibility and 55 articles were included. Evidence was found for the ACoA syndrome in studies between 1960 and 2000, with impairments in memory and executive problems in the majority of studies. However, the majority of studies from 2000 did not demonstrate a distinct ACoA syndrome, although neuropsychological measurements improved. This coincides with the changes in the management of ACoA aneurysms over the past decades, such as the emergence of endovascular treatment and improvement of neurointensive care. Therefore, we hypothesize that the management techniques of ACoA aneurysms until around 2000, i.e. mainly conventional clipping, could be related to the presence of symptoms of the ACoA syndrome.

Influence of magnetic field on a novel scintillation dosimeter in a 1.5 T MR-linac.

For commissioning and quality assurance for adaptive workflows on the MR-linac, a dosimeter which can measure time-resolved dose during MR image acquisition is desired. The Blue Physics model 10 scintillation dosimeter is potentially an ideal detector for such measurements. However, some detectors can be influenced by the magnetic field of the MR-linac. To assess the calibration methods and magnetic field dependency of the Blue Physics scintillator in the 1.5 T MR-linac. Several calibration methods were assessed for robustness. Detector characteristics and the influence of the calibration methods were assessed based on dose reproducibility, dose linearity, dose rate dependency, relative output factor (ROF), percentage depth dose profile, axial rotation and the radial detector orientation with respect to the magnetic field. The potential application of time-resolved dynamic dose measurements during MRI acquisition was assessed. A variation of calibration factors was observed for different calibration methods. Dose reproducibility, dose linearity and dose rate stability were all found to be within tolerance and were not significantly affected by different calibration methods. Measurements with the detector showed good correspondence with reference chambers. The ROF and radial orientation dependence measurements were influenced by the calibration method used. Axial detector dependence was assessed and relative readout differences of up to 2.5% were observed. A maximum readout difference of 10.8% was obtained when rotating the detector with respect to the magnetic field. Importantly, measurements with and without MR image acquisition were consistent for both static and dynamic situations. The Blue Physics scintillation detector is suitable for relative dosimetry in the 1.5 T MR-linac when measurements are within or close to calibration conditions.

Quality assurance of radiation therapy after breast-conserving surgery among patients in the BOOG 2013-08 trial.

BACKGROUND AND PURPOSE: In the BOOG 2013-08 trial (NCT02271828), cT1-2N0 breast cancer patients were randomized between breast conserving surgery with or without sentinel lymph node biopsy (SLNB) followed by whole breast radiotherapy (WBRT). While awaiting primary endpoint results (axillary recurrence rate), this study aims to perform a quality assurance analysis on protocol adherence and (incidental) axillary radiation therapy (RT) dose. MATERIALS AND METHODS: Patients were enrolled between 2015 and 2022. Data on prescribed RT and (in 25% of included patients) planning target volumes (PTV) parameters were recorded for axillary levels I-IV and compared between treatment arms. Multivariable linear regression analysis was performed to determine prognostic variables for incidental axillary RT dose. RESULTS: 1,439/1,461 included patients (98.5%) were treated according to protocol and 87 patients (5.9%) received regional RT (SLNB 10.9%, no-SLNB 1.5 %). In 326 patients included in the subgroup analysis, the mean incidental PTV dose at axilla level I was 59.5% of the prescribed breast RT dose. In 5 patients (1.5%) the mean PTV dose at level I was ≥95% of the prescribed breast dose. No statistically or clinically significant differences regarding incidental axillary RT dose were found between treatment arms. Tumour bed boost (yes/no) was associated with a higher incidental mean dose in level I (R2 = 0.035, F(6, 263) = 1.532, p 0.168). CONCLUSION: The results indicate that RT-protocol adherence was high, and that incidental axillary RT dose was low in the BOOG 2013-08 trial. Potential differences between treatmentarms regarding the primary endpoint can thus not be attributed to different axillary radiation doses.

Experimental validation of multi-fraction online adaptations in magnetic resonance guided radiotherapy.

Background and purpose: Radiotherapy plan verification is generally performed on the reference plan based on the pre-treatment anatomy. However, the introduction of online adaptive treatments demands a new approach, as plans are created daily on different anatomies. The aim of this study was to experimentally validate the accuracy of total doses of multi-fraction plan adaptations in magnetic resonance imaging guided radiotherapy in a phantom study, isolated from the uncertainty of deformable image registration. Materials and methods: We experimentally verified the total dose, measured on external beam therapy 3 (EBT3) film, using a treatment with five online adapted fractions. Three series of experiments were performed, each focusing on a category of inter-fractional variation; translations, rotations and body modifications. Variations were introduced during each fraction and adapted plans were generated and irradiated. Single fraction doses and total doses over five online adapted fractions were investigated. Results: The online adapted measurements and calculations showed a good agreement for single fractions and multi-fraction treatments for the dose profiles, gamma passing rates, dose deviations and distances to agreement. The gamma passing rate using a 2%/2 mm criterion ranged from 99.2% to 99.5% for a threshold dose of 10% of the maximum dose (Dmax) and from 96.2% to 100% for a threshold dose of 90% of Dmax, for the total translations, rotations and body modifications. Conclusions: The total doses of multi-fraction treatments showed similar accuracies compared to single fraction treatments, indicating an accurate dosimetric outcome of a multi-fraction treatment in adaptive magnetic resonance imaging guided radiotherapy.

Variations in small-scale movements of, Rousettus aegyptiacus, a Marburg virus reservoir across a seasonal gradient.

BACKGROUND: Bats are increasingly being recognized as important hosts for viruses, some of which are zoonotic and carry the potential for spillover within human and livestock populations. Biosurveillance studies focused on assessing the risk of pathogen transmission, however, have largely focused on the virological component and have not always considered the ecological implications of different species as viral hosts. The movements of known viral hosts are an important component for disease risk assessments as they can potentially identify regions of higher risk of contact and spillover. As such, this study aimed to synthesize data from both virological and ecological fields to provide a more holistic assessment of the risk of pathogen transmission from bats to people. RESULTS: Using radiotelemetry, we tracked the small-scale movements of Rousettus aegyptiacus, a species of bat known to host Marburg virus and other viruses with zoonotic potential, in a rural settlement in Limpopo Province, South Africa. The tracked bats exhibited seasonal variations in their movement patterns including variable usage of residential areas which could translate to contact between bats and humans and may facilitate spillover. We identified a trend for increased usage of residential areas during the winter months with July specifically experiencing the highest levels of bat activity within residential areas. July has previously been identified as a key period for increased spillover risk for viruses associated with R. aegyptiacus from this colony and paired with the increased activity levels, illustrates the risk for spillover to human populations. CONCLUSION: This study emphasizes the importance of incorporating ecological data such as movement patterns with virological data to provide a better understanding of the risk of pathogen spillover and transmission.

Clinical Applications of Conebeam CTP Imaging in Cerebral Disease: A Systematic Review.

BACKGROUND: Perfusion imaging with multidetector CT is integral to the evaluation of patients presenting with ischemic stroke due to large-vessel occlusion. Using conebeam CT perfusion in a direct-to-angio approach could reduce workflow times and improve functional outcome. PURPOSE: Our aim was to provide an overview of conebeam CT techniques for quantifying cerebral perfusion, their clinical applications, and validation. DATA SOURCES: A systematic search was performed for articles published between January 2000 and October 2022 in which a conebeam CT imaging technique for quantifying cerebral perfusion in human subjects was compared against a reference technique. STUDY SELECTION: Eleven articles were retrieved describing 2 techniques: dual-phase (n = 6) and multiphase (n = 5) conebeam CTP. DATA ANALYSIS: Descriptions of the conebeam CT techniques and the correlations between them and the reference techniques were retrieved. DATA SYNTHESIS: Appraisal of the quality and risk of bias of the included studies revealed little concern about bias and applicability. Good correlations were reported for dual-phase conebeam CTP; however, the comprehensiveness of its parameter is unclear. Multiphase conebeam CTP demonstrated the potential for clinical implementation due to its ability to produce conventional stroke protocols. However, it did not consistently correlate with the reference techniques. LIMITATIONS: The heterogeneity within the available literature made it impossible to apply meta-analysis to the data. CONCLUSIONS: The reviewed techniques show promise for clinical use. Beyond evaluating their diagnostic accuracy, future studies should address the practical challenges associated with implementing these techniques and the potential benefits for different ischemic diseases.

Eye-tracking visual patterns of sonographers with and without fetal motor assessment expertise.

OBJECTIVES: Fetal motor assessment (FMA) in addition to structural anomaly scan enhances prenatal detection of arthrogryposis multiplex congenita (AMC). In the Amsterdam UMC, sonographers are trained to perform FMA. We examined the effect of motor assessment training by comparing sonographers with (SMA) and without this training (S) on their qualitative motor assessment in fetuses with normal (FNM) and abnormal motility (FAM) and their visual processing by eye-tracking. METHODS: The study was performed from 2019 to 2020. Five SMA and five S observed five FNM and five FAM videos. Qualitative FMA consisted of six aspects of the general movement and the overall conclusion normal or abnormal. The visual processing aspects examined through eye-tracking were fixation duration, number of revisits per region of interest (ROI) and scanpaths of saccades between fixation points. RESULTS: Quality assessment by SMA revealed more correct aspects in FNM than in FAM but overall conclusions were equally correct (92-96 %). S scored aspects of FNM better than in FAM, but overall conclusion correct only in half of FNM and three quarters of FAM. Eye-tracking of SMA and S showed fixation duration and revisits with similar distributions per ROIs for FNM and FAM, but SMA perform more trunk revisits in FNM. Scanpaths had smaller circumference, less outliers and more consistency in SMA than S. CONCLUSION: This modest population of qualified sonographers showed that additional FMA training improved qualitative motor assessment. Eye-tracking revealed differences in visual processing and stimulates continuous education for professionals active in the detection of these rare diseases.

Every maternal near-miss counts: Need for a national audit in South Africa? A mixed-methods study.

BACKGROUND: To improve maternal health, studies of maternal morbidity are increasingly being used to evaluate the quality of maternity care, in addition to studies of mortality. While South Africa (SA) has a well-established confidential enquiry into maternal deaths, there is currently no structure in place to systematically collect and analyse maternal near-misses (MNMs) at national level. OBJECTIVES: To synthesise MNM indicators and causes in SA by performing a systematic literature search, and to investigate perceived needs for data collection related to MNMs and determine whether the MNM tool from the World Health Organization (WHO-MNM) would require adaptations in order to be implemented. METHODS: The study used a mixed-methods approach. A systematic literature search was conducted to find all published data on MNM audits in SA. Semi-structured interviews were conducted virtually with maternal health experts throughout the country who had been involved in studies of MNMs, and main themes arising in the interviews were synthesised. A method for MNM data collection for SA use was discussed with these experts. RESULTS: The literature search yielded 797 articles, 15 of which met the WHO-MNM or Mantel et al. severe acute maternal morbidity criteria. The median (interquartile range) MNM incidence ratio in SA was 8.4/1 000 (5.6 - 8.7) live births, the median maternal mortality ratio was 130/100 000 (71.4 - 226) live births, and the median mortality index was 16.6% (11.7 - 18.8). The main causes of MNMs were hypertensive disorders of pregnancy and obstetric haemorrhage. Eight maternal health experts were interviewed from May 2020 to February 2021. All participants focused on the challenges of implementing a national MNM audit, yet noted the urgent need for one. Recognition of MNMs as an indicator of quality of maternity care was considered to lead to improved management earlier in the chain of events, thereby possibly preventing mortality. Obtaining qualitative information from women with MNMs was perceived as an important opportunity to improve the maternity care system. Participants suggested that the WHO-MNM tool would have to be adapted into a simplified tool with more clearly defined criteria and a number of specific diagnoses relevant to the SA setting. This 'Maternal near-miss: Inclusion criteria and data collection form' is provided as a supplementary file. CONCLUSION: Adding MNMs to the existing confidential maternal death enquiry could potentially contribute to a more robust audit with data that may inform health systems planning. This was perceived by SA experts to be valuable, but would require context-specific adaptations to the WHO-MNM tool. The available body of evidence is sufficient to justify moving to implementation.

Dosimetric evaluation of off-axis fields and angular transmission for the 1.5 T MR-linac.

Objective.GPU-oriented Monte Carlo dose (GPUMCD) is a fast dose calculation algorithm used for treatment planning on the Unity MR-linac. Treatments for the MR-linac must be calculated quickly and accurately, and must account for two important MR-linac aspects: off-axis positions and angular transmission through the cryostat, couch and MR-coils. Therefore, the aim of this research is to quantify the system-related errors for GPUMCD calculations over the range of clinically-relevant field configurations and gantry angles.Approach.Dose profiles (crossline, inline and PDD) were measured and calculated for varying field sizes, off-axis positions and depths. Eleven different (off-axis) positions were included. The angular transmission was investigated by measuring and calculating the transmission for multiple angles, taking the cryostat, couch and coils into account.Main results.Differences between absolute point doses were found to be within 1.7% for field sizes 2 × 2 cm2and larger. The relative dose profiles in the crossline, inline and PDD direction illustrated maximum mean dose differences of 0.9pp, 0.8pp and 0.7pp ofDmaxin the central region for field sizes 2 × 2 cm2and larger. The 1 × 1 cm2field size showed larger dosimetric errors for absolute point doses and relative dose profiles. The maximum mean DTA in the penumbra was 0.7 mm. The mean difference in angular transmission ranged from -0.33% ± 0.60% to 0.27% ± 0.91% using three treatment machines. Additionally, 77.1%-93.7% of the datapoints remained within 1% transmission difference. The largest transmission differences were present at the edges of the table.Significance.This research showed that the GPUMCD algorithm provides reliable dose calculations with a low uncertainty for field sizes 2 × 2 cm2and larger, focusing on off-axis fields and angular transmission.

Implications of fetal premature atrial contractions: systematic review.

OBJECTIVE: Fetal heart-rate irregularities occur in 1-2% of pregnancies and are usually caused by premature atrial contractions (PAC). Although PAC are considered benign, they may be associated with cardiac defects and tachyarrhythmia. We aimed to determine the incidence of congenital heart defects (CHDs) and complications in fetuses with PAC. METHODS: This was a systematic review and meta-analysis conducted in accordance with the PRISMA statement for reporting items for systematic reviews and meta-analyses. MEDLINE and EMBASE were searched from 1990 to June 2021 to identify studies on fetuses with PAC. The primary outcome was CHD; secondary outcomes were complications using the endpoints supraventricular tachyarrhythmia (SVT), cardiac failure and intrauterine fetal demise. Meta-analysis of proportions was performed, subdivided into high-risk and low-risk populations based on reason for referral. Pooled incidences with 95% CIs were calculated. RESULTS: Of 2443 unique articles identified, 19 cohort studies including 2260 fetuses were included. The pooled incidence of CHD in fetuses with PAC was 2.8% (95% CI, 1.5-4.1%), when 0.6% is the incidence expected in the general population. The pooled incidence of CHD was 7.2% (95% CI, 3.5-10.9%) in the high-risk population and 0.9% (95% CI, 0.0-2.0%) in the low-risk population. SVT occurred in 1.4% (95% CI, 0.6-3.4%) of fetuses diagnosed with PAC. Cardiac failure was described in 16 fetuses (1.4% (95% CI, 0.5-3.5%)), of which eight were CHD-related. Intrauterine fetal demise occurred in four fetuses (0.9% (95% CI, 0.5-1.7%)) and was related to CHD in two cases. CONCLUSIONS: Our findings suggest that the risk of CHD in fetuses with PAC is 4-5 times higher than that in the general population. CHD was present more frequently in the high-risk population. Consequently, an advanced ultrasound examination to diagnose PAC correctly and exclude CHD is recommended. Complications of PAC are rare but can result in fetal demise, thus weekly fetal heart-rate monitoring remains advisable to enable early detection of SVT and to prevent cardiac failure. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Autoimmune Encephalitis With mGluR1 Antibodies Presenting With Epilepsy, but Without Cerebellar Signs: A Case Report.

OBJECTIVE: To describe the unique case history of a patient with mGluR1 antibodies, with mainly limbic and without cerebellar symptoms. METHODS: A 50-year-old woman initially presented with focal seizures with epigastric rising and déjà-vu sensations, next to cognitive complaints, and musical auditory hallucinations. MRI, EEG, and neuronal autoantibody tests were performed. RESULTS: EEG findings showed slow and sharp activity (sharp waves and sharp-wave-slow-wave complex) in the left temporal lobe. A test for autoantibodies was negative initially. Because of persistent symptoms, serum and CSF were tested 4 years later and found positive for mGluR1 antibodies. Treatment started with monthly IV immunoglobulins and azathioprine that was replaced by mycophenolate mofetil later. Especially cognitive symptoms and hallucinations did not respond well to the treatment. During treatment, mGluR1 antibodies remained present in CSF. DISCUSSION: Whereas cerebellar symptoms are present in 97% of mGluR1-positive cases, our patient presented without ataxia. Therefore, we suggest that the clinical presentation of patients with mGluR1 antibodies is probably more diverse than previously described. Testing for mGluR1 antibodies should be considered in patients with limbic encephalitis and epilepsy, especially when negative for more common antibodies.

The Summer School Oncology Groningen: Improving a Successful International Course by Refining the Old, Maintaining What's Good.

For more than two decades, the International Summer School Oncology for Medical Students (ISOMS) has organized a biennial 2-week international summer school program in Groningen, the Netherlands. The summer school aims to increase knowledge about general cancer care, reduce fear of talking to cancer patients, and expose students to cancer-related problems. After 22 years, there was a need to improve the summer school format, the application procedure, and the intensity of the course. Here, we describe and evaluate these and additional changes that were made to the program. Several changes were made to the summer school format. The course was shortened from 10 days to a more intensive 7 days. The scientific program was integrated with the clinical program and students were taught scientific writing and presentation skills. The application process involved a personal video pitch. Importantly, the new summer school format was organized by a committee in which medical students had the lead. To evaluate the changes to the summer school, we conducted knowledge tests and regularly obtained feedback. There was a high overall student satisfaction, with a median score of a 9 out of 10. Students appreciated the interactive sessions and practicals and the scientific program, and were satisfied with the course level. All students had improved test scores. Improvement points highlighted the need for a less packed schedule and more lectures on basic oncology principles, or were related to specific lectures. The student-led innovation and adaptation of the ISOMS has been successful.

A Comparison of Health Status and Quality of Life in Patients with Intermittent Claudication.

BACKGROUND: Patient reported outcome measures (PROMs) such as health status (HS) and quality of life (QOL) are frequently used interchangeably while they represent different outcomes. Whether a discrepancy exists in patients with intermittent claudication (IC) in changes over time between HS and QOL is unclear. This study aimed to investigate the strength and the direction of the association between HS and QOL over time in patients with IC that underwent supervised exercise therapy (SET). MATERIAL AND METHODS: Patients were part of the ELECT multi-center prospective cohort study. One goal of this study was to obtain data on HS and QOL at different time intervals of patients with IC that underwent SET. HS (VascuQOL-6) and QOL (WHOQOL-BREF) were completed at baseline, 3 months, and 6 months follow up. Pearson's correlation coefficients and the associated common variances (R2) were calculated to measure the strength and the direction of the association between HS and QOL in changes between baseline and follow-up moments. RESULTS: In total, 177 patients were included in data analyses. Only changes in physical QOL and overall QOL had a small correlation with changes over time in HS, at both 3- and 6 months follow up (respectively R2=.14; P < 0.001 and R2 = 0.12; P < 0.001 for physical QOL and R2 = 0.18; P < 0.001 and R2 = 0.13; P < 0.001 for overall QOL). CONCLUSIONS: This study showed that HS and QOL provide different outcomes in patients with IC that underwent SET. Future studies should be aware of these differences before PROMs are being incorporated as an outcome measure in clinical studies.

Inheritance of physico-chemical properties and ROS generation by carbon quantum dots derived from pyrolytically carbonized bacterial sources.

Bacteria are frequently used in industrial processes and nutrient supplementation to restore a healthy human microflora, but use of live bacteria is often troublesome. Here, we hypothesize that bacterially-derived carbon-quantum-dots obtained through pyrolytic carbonization inherit physico-chemical properties from probiotic and pathogenic source-bacteria. Carbon-quantum-dots carbonized at reaction-temperatures below 200 â€‹°C had negligible quantum-yields, while temperatures above 220 â€‹°C yielded poor water-suspendability. Fourier-transform infrared-spectroscopy demonstrated preservation of amide absorption bands in carbon-quantum-dots derived at intermediate temperatures. X-ray photoelectron-spectroscopy indicated that the at%N in carbon-quantum-dots increased with increasing amounts of protein in source-bacterial surfaces. Carbonization transformed hydrocarbon-like bacterial surface compounds into heterocyclic aromatic-carbon structures, evidenced by a broad infrared absorption band (920-900 â€‹cm-1) and the presence of carbon in C-C functionalities of carbon-quantum-dots. The chemical composition of bacterially-derived carbon-quantum-dots could be explained by the degradation temperatures of main bacterial cell surface compounds. All carbon-quantum-dots generated reactive-oxygen-species, most notably those derived from probiotic lactobacilli, carrying a high amount of surface protein. Concluding, amide functionalities in carbon-quantum-dots are inherited from surface proteins of source-bacteria, controlling reactive-oxygen-species generation. This paves the way for applications of bacterially-derived carbon-quantum-dots in which reactive-oxygen-species generation is essential, instead of hard-to-use live bacteria, such as in food supplementation or probiotic-assisted antibiotic therapy.

The accuracy of gap and step-off measurements in acetabular fracture treatment.

The assessment of gaps and steps in acetabular fractures is challenging. Data from various imaging techniques to enable accurate quantification of acetabular fracture displacement are limited. The aim of this study was to assess the accuracy of pelvic radiographs, intraoperative fluoroscopy, and computed tomography (CT) in detecting gaps and step-offs in acetabular fractures. Sixty patients, surgically treated for acetabular fractures, were included. Five observers (5400 measurements) measured the gaps and step-offs on radiographs and CT scans. Intraoperative fluoroscopy images were reassessed for the presence of gaps and/or step-offs. Preoperatively, 25% of the gaps and 40% of the step-offs were undetected on radiographs compared to CT. Postoperatively, 52% of the gaps and 80% of the step-offs were missed on radiographs compared to CT. Radiograph analysis led to a significantly smaller gap and step-off compared to the CT measurements, an underestimation by a factor of two. Approximately 70% of the residual gaps and step-offs was not detected using intraoperative fluoroscopy. Gaps and step-offs that exceed the critical cut-off indicating worse prognosis often remained undetected on radiographs compared to CT scans. Less-experienced observers tend to overestimate gaps and step-offs compared to the more-experienced observers. In acetabular fracture treatment, gaps and step-offs were often undetected and underestimated on radiographs and intraoperative fluoroscopy in comparison with CT scans. This means that CT is superior to radiographs in detecting acetabular fracture displacement, which is clinically relevant for patient counselling regarding treatment decisions and prognosis.

Acceptance procedure for the linear accelerator component of the 1.5 T MRI-linac.

PURPOSE: To develop and implement an acceptance procedure for the new Elekta Unity 1.5 T MRI-linac. METHODS: Tests were adopted and, where necessary adapted, from AAPM TG106 and TG142, IEC 60976 and NCS 9 and NCS 22 guidelines. Adaptations were necessary because of the atypical maximum field size (57.4 × 22 cm), FFF beam, the non-rotating collimator, the absence of a light field, the presence of the 1.5 T magnetic field, restricted access to equipment within the bore, fixed vertical and lateral table position, and the need for MR image to MV treatment alignment. The performance specifications were set for stereotactic body radiotherapy (SBRT). RESULTS: The new procedure was performed similarly to that of a conventional kilovoltage x-ray (kV) image guided radiation therapy (IGRT) linac. Results were acquired for the first Unity system. CONCLUSIONS: A comprehensive set of tests was developed, described and implemented for the MRI-linac. The MRI-linac met safety requirements for patients and operators. The system delivered radiation very accurately with, for example a gantry rotation locus of isocenter of radius 0.38 mm and an average MLC absolute positional error of 0.29 mm, consistent with use for SBRT. Specifications for clinical introduction were met.

Knowledge, health beliefs and attitudes towards dementia and dementia risk reduction among descendants of people with dementia: a qualitative study using focus group discussions.

BACKGROUND: Individuals with a parental family history of dementia have an increased risk of developing dementia because they share their genes as well as their psychosocial behaviour. Due to this increased risk and their experience with dementia, they may be particularly eager to receive information regarding dementia risk reduction (DRR). This study evaluated the knowledge, beliefs and attitudes towards dementia and DRR among descendants of people with dementia. METHOD: Using a semi-structured topic guide, three focus group discussions were conducted consisting of 12 female (80%) and 3 male (20%) descendants of people with dementia with a mean (± SD) age of 48.8 (± 12) years. Focus group discussions were audio recorded and transcribed. Each transcript was analysed thoroughly, and where appropriate, a code was generated and assigned by two researchers independently. Then, similar codes were grouped together and categorized into themes. RESULTS: The items in the topic guide could only be addressed after participants had been given the opportunity to share their experiences of having a parent with dementia. Participants were unaware or uncertain about the possibility of reducing the risk of developing dementia and therefore hesitant to assess their dementia risk without treatment options in sight. Moreover, participants indicated that their general practitioner only gave some information on heritability, not on DRR. Although participants identified a large number of modifiable risk factors as a group during the group discussions, they were eager to receive more information on dementia and DRR. In the end, participants adopted a more positive attitude towards a DRR programme and provided suggestions for the development of future DRR programmes. CONCLUSIONS: Although the research aim was to evaluate the knowledge, beliefs and attitudes towards dementia and DRR, sharing experiences of having a parent with dementia seemed a prerequisite for considering participants' own risk of developing dementia and participating in a DRR programme. Knowledge of dementia and DRR was limited. Due to unawareness of the possibility of reducing dementia risk, participants were hesitant about assessing their dementia risk. Group discussions positively changed the perception of dementia risk assessment and participants' willingness to participate in a DRR programme.

Micronutrient deficiencies in critical illness.

BACKGROUND & AIMS: Low micronutrient levels in critical illness have been reported in multiple studies. Because of the antioxidant properties of various micronutrients, micronutrient deficiency may augment oxidative stress in critical illness. However, it remains unclear whether micronutrient concentrations in ICU patients are different from those in healthy age-matched controls. It is also unclear whether micronutrient deficiency develops, worsens, or resolves during ICU admission without supplementation. METHODS: We prospectively studied a cohort of adult critically ill patients. Micronutrient levels, including selenium, ß-carotene, vitamin C, E, B1 and B6 were measured repeatedly during the first week of ICU admission. We compared the micronutrient concentrations at ICU admission to those of healthy age-matched controls. In addition, associations between micronutrient concentrations with severity of illness, inflammation and micronutrient intake were investigated. RESULTS: Micronutrient blood concentrations were obtained from 24 critically ill adults and 21 age-matched healthy controls. The mean micronutrient levels at admission in the ICU patients were: selenium 0.52 µmol/l, ß-carotene 0.17 µmol/l, vitamin C 21.5 µmol/l, vitamin E 20.3 µmol/l, vitamin B1 129.5 nmol/l and vitamin B6 41.0 nmol/l. In the healthy controls micronutrient levels of selenium (0.90 µmol/l), ß-carotene (0.50 µmol/l), vitamin C (45 µmol/l) and vitamin E (35.5 µmol/l) were significantly higher, while vitamin B1 (122 nmol/l) and B6 (44 nmol/l) were not significantly different between patients and controls. Selenium, vitamin B1 and vitamin B6 levels remained stable during ICU admission. Vitamin C levels dropped significantly until day 5 (p < 0.01). Vitamin E and ß-carotene levels increased significantly on days 5-7 and day 7, respectively (p < 0.01). Micronutrient levels were not associated with severity of illness, CRP or micronutrient intake during the admission. CONCLUSIONS: At admission, ICU patients already had lower plasma levels of selenium, ß-carotene, vitamin C and vitamin E than healthy controls. Vitamin C levels dropped significantly during the first days of ICU admission, while ß-carotene and vitamin E levels increased after 5-7 days. No association between micronutrient levels and severity of illness, C-reactive protein (CRP) or micronutrient intake was found. Progressive enteral tube feeding containing vitamins and trace elements does not normalize plasma levels in the first week of ICU stay. This was a hypothesis generating study and more investigation in a larger more diverse sample is needed.

Baby's first bites: Association between observed maternal feeding behavior and infant vegetable intake and liking.

Positive experiences with the introduction of solid food in infancy may lead to positive associations with feeding in both parent and infant. During this transitional period, parental feeding behavior and infant eating behavior might mutually reinforce each other. A feeding style that is found to be associated with positive child eating behavior, is sensitive feeding. In the present study we tested bidirectional prospective relations between mother and infant behavior in a cross-lagged model using observations of two feeds on two consecutive days on which the first bites of solid food were offered. The sample consisted of 246 first-time mothers and their infants, whose feeding interactions were videotaped during two home visits. Maternal sensitive feeding behavior (consisting of responsiveness to child feeding cues, general sensitivity and non-intrusiveness) and maternal positive and negative affect were coded. In addition, infant vegetable intake was weighed and vegetable liking was reported by mother. Results showed at least some stability of maternal feeding behavior and infant vegetable intake and liking from the first to the second feed. In addition, during the second feed maternal sensitive feeding and positive affect were associated with infant vegetable intake (r=.34 and r=.14) and liking (r=.33 and r=.39). These associations were mostly absent during the first feed. Finally, infant vegetable liking during the first feed positively predicted maternal sensitive feeding behavior during the second feed (ß=.25), suggesting that the infant's first response might influence maternal behavior. Taken together, mother and infant seem more attuned during the second feed than during the first feed. Future studies might include multiple observations over a longer time period, or micro-coding. Such insights can inform prevention programs focusing on optimizing feeding experiences during the weaning period.