Assessing Displacement of Plastic Interstitial Catheters in Image-Guided Gynecological HDR Brachytherapy

PURPOSE/OBJECTIVE(S)

Interstitial HDR brachytherapy involves precise, localized delivery to targets with high dose gradients, sparing adjacent organs at risk. Due to the proximity of the rectum and bladder to the target, deviations in the catheters with respect to patient anatomy can change dose to those structures. While utilizing plastic interstitial catheters allows the patient to receive hyperthermia therapy during their course of interstitial treatment, the plastic catheters were observed to show significant deflection when the metal stylets are removed for treatment. The hyperthermia electrodes and the HDR source cable are both wires of approximately the same thickness. The purpose of this study is to assess the magnitude and deflection of the plastic catheters for gynecologic interstitial plans and determine whether using flexible wires for visualization on pre-treatment imaging is suitable for reconstructing the actual treatment received.

MATERIALS/METHODS

Pre-treatment CT images where the stylets were utilized for catheter visualization were registered to a subsequent CT scan with the metal stylets removed. The original treatment dwell positions were adjusted to the second CT to evaluate 3D catheter displacement and dose distributions calculated for the bladder, rectum, and target. The plans were subsequently reconstructed on a pre-planning CT with flexible 20-gauge wires instead of metal stylets to determine their suitability as a surrogate for stylets.

RESULTS

Absolute 3D displacement for all patients was 3.5 ± 5.4 mm (n = 3433 catheter dwell positions, mean ± SD, p < 0.001) comparing plans with the stylet in versus out. Absolute catheter deflection for interstitial treatments increased with the removal of the metal stylets with a difference of 0.75 ± 0.49° (n = 313 catheters, mean ± SD, p < 0.01). The plans utilizing flexible wire instead of stylets are observed to correlate with the plans with no stylets with absolute 3D displacement and angular deflection of 1.1 ± 0.6 mm and 0.35° ± 0.3° respectively (n = 39 catheters, mean ± SD, p > 0.2). While the average target EQD2 D90 reduced by 5% ± 5% by planning without the stylets, four patients would have experienced a deviation from the prescription by >10%. There was an overall decrease in bladder D2cc and overall increase in rectal D2cc in the plans with the stylets utilized vs removed. Bladder D2cc, rectal D2cc, and target coverage showed no appreciable difference between utilizing flexible wires and the plans without. The difference in HU between the metal stylets and flexible wires was negligible.

CONCLUSION

Catheter reconstruction in interstitial gynecological treatments with CT imaging revealed significant changes in catheter positioning with respect to the target volume once the stylets are removed for treatment. Using flexible wires of similar thickness to the source cable allow for more accurate tracking during planning without distorting the patient's anatomy or the treatment images, preserving the integrity of the treatment plan.

Resilience in adolescence during the COVID-19 crisis in Canada

BACKGROUND

The COVID-19 pandemic constitutes a social crisis that will have long-term health consequences for much of the global population, especially for adolescents. Adolescents are triply affected as they: 1) are experiencing its immediate, direct effects, 2) will carry forward health habits they develop now into adulthood, and 3) as future parents, will shape the early life health of the next generation. It is therefore imperative to assess how the pandemic is influencing adolescent wellbeing, identify sources of resilience, and outline strategies for attenuating its negative impacts.

METHODS

We report the results of longitudinal analyses of qualitative data from 28 focus group discussions (FGDs) with 39 Canadian adolescents and of cross-sectional analyses of survey data from 482 Canadian adolescents gathered between September 2020 and August 2021. FGD participants and survey respondents reported on their: socio-demographic characteristics; mental health and wellbeing before and during the pandemic; pre- and during-pandemic health behaviours; experiences living through a crisis; current perceptions of their school, work, social, media, and governmental environments; and ideas about pandemic coping and mutual aid. We plotted themes emerging from FGDs along a pandemic timeline, noting socio-demographic variations. Following assessment for internal reliability and dimension reduction, quantitative health/wellbeing indicators were analyzed as functions of composite socio-demographic, health-behavioural, and health-environmental indicators.

RESULTS

Our mixed methods analyses indicate that adolescents faced considerable mental and physical health challenges due to the pandemic, and were generally in poorer health than expected in non-crisis times. Nevertheless, some participants showed significantly better outcomes than others, specifically those who: got more exercise; slept better; were food secure; had clearer routines; spent more time in nature, deep in-person social relationships, and leisure; and spent less time on social media.

CONCLUSIONS

Support for youth during times of crisis is essential to future population health because adolescence is a period in the life course which shapes the health behaviours, socio-economic capacities, and neurophysiology of these future parents/carers and leaders. Efforts to promote resilience in adolescents should leverage the factors identified above: helping them find structure and senses of purpose through strong social connections, well-supported work and leisure environments, and opportunities to engage with nature.

Speakers prioritise affordance-based object semantics in scene descriptions

This work investigates the linearisation strategies used by speakers when describing real-world scenes to better understand production plans for multi-utterance sequences. In this study, 30 participants described real-world scenes aloud. To investigate which semantic features of scenes predict order of mention, we quantified three features (meaning, graspability, and interactability) using two techniques (whole-object ratings and feature map values). We found that object-level semantic features, namely those affordance-based, predicted order of mention in a scene description task. Our findings provide the first evidence for an object-related semantic feature that guides linguistic ordering decisions and offer theoretical support for the role of object semantics in scene viewing and description.

A91 CANADIAN FEMALE FELLOW PERSPECTIVES ON TRAINING IN THE BOYS CLUB: ADVANCED THERAPEUTIC ENDOSCOPY

Background

Unequal female representation in the field of advanced therapeutic endoscopy (ATE) has been recently highlighted in the United States. Previous attempts to determine the barriers of entry into the career have found reasons including lack of mentorship, patriarchy, inflexible hours/call and exposure to fluoroscopy. There is no current literature describing the landscape of exposure to ATE for trainees in Canada or determining differences in experience based on gender.

Aims

We sought to determine the barriers to pursuing a career in advanced therapeutic endoscopy, specifically focussing on the perspectives of Canadian female gastroenterology fellows.

Methods

A survey was developed and distributed to the gastroenterology fellows enrolled in Royal College accredited programs across Canada via an online survey platform.

Results

Responses were received from gastroenterology fellows at 12 out of the 14 Canadian universities with Royal College accredited programs. The response rate was 46% (n=42, 16 female respondents, 26 male respondents). An equal proportion of male (42%, n=11) and female (38%, n=6) trainees indicated interest in a career in ATE. 38% (n=6) of female trainees felt that they had inadequate mentorship opportunities/role models within ATE, in comparison to 4% (n=1) of males (p=0.004). Furthermore, 19% (n=3) of females felt that this lack of mentorship/role models was a primary deterrent from pursuing ATE as a career, in comparison to 0% of males (p=0.02). There was equal self-perceived competency surrounding ATE knowledge between both genders.

Conclusions

Female gastroenterology fellows in Canada lack mentorship and role models in ATE, which they also indicated as a primary deterrent from pursuing it as a career when compared to their male counterparts. Recognizing and addressing the lack of female leadership and visibility is necessary to improve parity and encourage women to train in the male-dominated field of ATE.

Funding Agencies

None

Meeting the UK Government's prevention agenda: primary care practitioners can be trained in skills to prevent disease and support self-management

Aims:

The NHS Long Term Plan has a prevention focus and ambition to support patients to self-manage disease through improving health behaviours. An essential requirement of self-management is behaviour change, but many practitioners have not been trained in skills to support behaviour change. ‘Healthy Conversation Skills’ (HCS) training was developed at the University of Southampton for this purpose. This article reports on a pilot study that aimed to assess the feasibility of primary care practitioners adopting HCS in their routine practice. It describes their experiences and level of competence post-training.

Methods:

Health Education England (Wessex) commissioned HCS training for 18 primary care practitioners. Fifteen of these practitioners were subsequently observed in their consultations at one or two time points; face-to-face semi-structured, reflective feedback interviews were conducted immediately following the observations. Practitioners’ HCS competence was assessed from the observations and interviews using a previously developed and published coding rubric. The interview data were analysed thematically to understand practitioners’ experiences of using the new skills.

Results:

Practitioners demonstrated competence in embedding the skills into their routine practice following HCS training. They reflected on how patients liked being asked questions, the usefulness of setting SMARTER (Specific, Measured, Action-oriented, Realistic, Timed, Evaluated and Reviewed) goals and the power of listening. They could also identify facilitators of skill use and ways to overcome challenges such as patients with competing priorities and organisational constraints. They found the skills valuable as a way of empowering patients to make changes to manage their own health.

Conclusions:

HCS are acceptable to primary care practitioners, can be readily adopted into their routine consultations and are a helpful strategy for supporting patients to make changes. HCS training has the potential to be a sustainable, scalable and effective way of contributing to the prevention agenda by supporting disease self-management, and hence of addressing today’s epidemic of lifestyle-related conditions.

Electric scooters: convenient transport or ED headache?

Electric scooters (e-scooters) provide a potentially attractive means of private transportation in the pandemic era, during which use of public transport is discouraged. E-scooter use has become widespread recently, and we have noticed a concomitant rise in related craniomaxillofacial injuries, often associated with alcohol consumption and lack of protective equipment. We present here the first-published UK data on electric scooter injuries which, in the post-lockdown period, included facial lacerations, mandibular and midface fractures, avulsed teeth, and cervical spine injury. We urge that forthcoming legislation make e-scooters subject to at least the same requirements in lighting, helmet wear, and sobriety as bicycles and that, in this way, their benefits can be enjoyed while reducing associated morbidity and mortality.

[Guidelines for the Management of Community Acquired Pneumonia in Children and Adolescents (Pediatric Community Acquired Pneumonia, pCAP) - Issued under the Responsibility of the German Society for Pediatric Infectious Diseases (DGPI) and the German Society for Pediatric Pulmonology (GPP)]

The present guideline aims to improve the evidence-based management of children and adolescents with pediatric community-acquired pneumonia (pCAP). Despite a prevalence of approx. 300 cases per 100 000 children per year in Central Europe, mortality is very low. Prevention includes infection control measures and comprehensive immunization. The diagnosis can and should be established clinically by history, physical examination and pulse oximetry, with fever and tachypnea as cardinal features. Additional signs or symptoms such as severely compromised general condition, poor feeding, dehydration, altered consciousness or seizures discriminate subjects with severe pCAP from those with non-severe pCAP. Within an age-dependent spectrum of infectious agents, bacterial etiology cannot be reliably differentiated from viral or mixed infections by currently available biomarkers. Most children and adolescents with non-severe pCAP and oxygen saturation > 92 % can be managed as outpatients without laboratory/microbiology workup or imaging. Anti-infective agents are not generally indicated and can be safely withheld especially in children of young age, with wheeze or other indices suggesting a viral origin. For calculated antibiotic therapy, aminopenicillins are the preferred drug class with comparable efficacy of oral (amoxicillin) and intravenous administration (ampicillin). Follow-up evaluation after 48 - 72 hours is mandatory for the assessment of clinical course, treatment success and potential complications such as parapneumonic pleural effusion or empyema, which may necessitate alternative or add-on therapy.

Exploring the acceptability of controlled human infection with SARSCoV2-a public consultation

Rapid development of an effective vaccine for SARSCoV2 is a global priority. A controlled human infection model (CHIM) would accelerate the efficacy assessment of candidate vaccines. This strategy would require deliberate exposure of volunteers to SARSCoV2 with no currently available treatment and a small but definite risk of serious illness or death. This raises complex questions about the social and ethical acceptability of risk to individuals, given the potential benefit to the wider population, and as such, a study cannot be done without public involvement. We conducted a structured public consultation with 57 individuals aged 20-40 years to understand public attitudes to a CHIM, and pre-requisites for enrolment. The overall response to this strategy was positive, and many would volunteer altruistically. Carefully controlled infection is viewed as safer than natural exposure to wild virus. The prolonged social isolation required for the proposed CHIM is considered an obstacle but not insurmountable, with reasonable compensation and supportive care. Given the significant level of public interest, a CHIM should be done as open science with regular, controlled dissemination of information into the public domain. Importantly, there was a strong view that the final decision whether to conduct a CHIM should be in the hands of qualified and experienced clinician-scientists and the authorities.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

0140 Dietary Macronutrients and Sleep Duration, Sleep Disturbance, and Daytime Fatigue

Introduction

We examined nationally-representative data on macronutrients associated with multiple dimensions of sleep health.

Methods

Data were obtained from the 2015–2016 National Health and Nutrition Examination Survey, (N=5,266 adults). Standard 24-h dietary recall procedures were analyzed to establish daily consumption of protein, carbohydrates, sugar, fiber, total fat, and saturated fat. Self-reported habitual sleep duration was categorized as very short (&lt;5h), short (5–6.5h), normal (7-8h), and long (&gt;8h). Sleep disturbance and daytime tiredness/fatigue were self-reported as either none, mild, moderate, or severe. Weighted multinomial logistic regressions with sleep variables as outcome/dependent variable and percent of each macronutrient as independent variable were adjusted for age, sex, race/ethnicity, education, and body mass index.

Results

Increased protein was associated with a decreased likelihood of very short sleep (RRR=0.01, p=0.019) and severe fatigue (RRR=0.06, p=0.020). Increased carbohydrates was associated with an increased likelihood of very short (RRR=61.17, p=0.001), short (RRR=3.96, p=0.017), and long (RRR=2.58, p=0.041) sleep, severe sleep disturbance (RRR=9.37, p=0.010) and fatigue (RRR=7.61, p=0.009). Increased sugar was associated with an increased likelihood of very short (RRR=24.17, p=0.001), short (RRR=3.29, p=0.017), and long (RRR=2.22, p=0.046) sleep, as well as mild (RRR=2.36, p=0.041) and severe (RRR=10.70, p=0.001) sleep disturbance, and severe fatigue (RRR=12.98, p&lt;0.0005). Increased fiber was associated with a decreased likelihood of long (RRR=0.01, p=0.032) sleep and severe sleep disturbance (RRR&lt;0.01, p&lt;0.0005), as well as moderate (RRR&lt;0.01, p=0.026) and severe (RRR&lt;0.01, p&lt;0.0005) fatigue. Increased fat was associated with a decreased likelihood of very short sleep (RRR=0.01, p=0.010). Increased saturated fat was associated with a decreased likelihood of very short sleep (RRR&lt;0.01, p=0.017).

Conclusion

Protein and fiber were associated with better sleep profiles overall and carbohydrate and sugar were associated with worse sleep, as well as increased prevalence of sleep disturbances and fatigue.

Support

Dr. Grandner is supported by R01MD011600

Improving pregnant women's diet and physical activity behaviours: the emergent role of health identity

Background

Women who gain too much weight in pregnancy are at increased risk of disease and of having children with increased risk. Interventions to improve health behaviours are usually designed for a general population of pregnant women, and trial outcomes show an average impact that does not represent the differences between individuals. To inform the development of future interventions, this study explored the factors that influenced women’s diet and physical activity during pregnancy and aimed to identify the needs of these women with regards to lifestyle support.

Methods

Women who completed a trial of vitamin D supplementation and nurse support in pregnancy were invited to take part in an interview. Seventeen women were interviewed about their lifestyles during pregnancy, the support they had, and the support they wanted. Interview transcripts were coded thematically and analysed to understand the factors that influenced the diets and physical activity levels of these women and their engagement with resources that could provide support.

Results

Women identified barriers to eating well or being physically active, and pregnancy-specific issues like nausea and pain were common. Women’s interest in maintaining a healthy lifestyle and their engagement with lifestyle support was related to the extent to which they self-identified as healthy people. Health-disengaged women were disinterested in talking about their lifestyles while health-focused women did not feel that they needed extra support. Women between these ends of the ‘health identity’ spectrum were interested in improving their health, and were able to identify barriers as well as sources of support.

Conclusions

Lifestyle interventions in pregnancy should be adapted to meet the needs of individuals with different health identities, and encouraging a change in health identity may be one way of supporting sustained change in health behaviours.

Who uses foodbanks and why? Exploring the impact of financial strain and adverse life events on food insecurity

Background

Rising use of foodbanks highlights food insecurity in the UK. Adverse life events (e.g. unemployment, benefit delays or sanctions) and financial strains are thought to be the drivers of foodbank use. This research aimed to explore who uses foodbanks, and factors associated with increased food insecurity.

Methods

We surveyed those seeking help from front line crisis providers from foodbanks (N = 270) and a comparison group from Advice Centres (ACs) (N = 245) in relation to demographics, adverse life events, financial strain and household food security.

Results

About 55.9% of foodbank users were women and the majority were in receipt of benefits (64.8%). Benefit delays (31.9%), changes (11.1%) and low income (19.6%) were the most common reasons given for referral. Compared to AC users, there were more foodbank users who were single men without children, unemployed, currently homeless, experiencing more financial strain and adverse life events (P = 0.001). Food insecurity was high in both populations, and more severe if they also reported financial strain and adverse life events.

Conclusions

Benefit-related problems appear to be a key reason for foodbank referral. By comparison with other disadvantaged groups, foodbank users experienced more financial strain, adverse life events, both increased the severity of food insecurity.

Translating the Developmental Origins of Health and Disease concept to improve the nutritional environment for our next generations: a call for a reflexive, positive, multi-level approach

Evidence supporting the Developmental Origins of Health and Disease (DOHaD) hypothesis indicates that improving early life environments can reduce non-communicable disease risks and improve health over the lifecourse. A widespread understanding of this evidence may help to reshape structures, guidelines and individual behaviors to better the developmental conditions for the next generations. Yet, few efforts have yet been made to translate the DOHaD concept beyond the research community. To understand why, and to identify priorities for DOHaD Knowledge Translation (KT) programs, we review here a portion of published descriptions of DOHaD KT efforts and critiques thereof. We focus on KT targeting people equipped to apply DOHaD knowledge to their everyday home or work lives. We identified 17 reports of direct-to-public DOHaD KT that met our inclusion criteria. Relevant KT programs have been or are being initiated in nine countries, most focusing on secondary school students or care-workers-in-training; few target parents-to-be. Early indicators suggest that such programs can empower participants. Main critiques of DOHaD KT suggest it may overburden mothers with responsibility for children's health and health environments, minimizing the roles of other people and institutions. Simultaneously, though, many mothers-to-be seek reliable guidance on prenatal health and nutrition, and would likely benefit from engagement with DOHaD KT. We thus recommend emphasizing solidarity, and bringing together people likely to one day become parents (youth), people planning pregnancies, expecting couples, care workers and policymakers into empowering conversation about DOHaD and about the importance and complexity of early life environments.

A Two Centre Observational Study of Simultaneous Pulse Oximetry and Arterial Oxygen Saturation Recordings in Intensive Care Unit Patients

The influence of variables that might affect the accuracy of pulse oximetry (SpO2) recordings in critically ill patients is not well established. We sought to describe the relationship between paired SpO2/SaO2 (oxygen saturation via arterial blood gas analysis) in adult intensive care unit (ICU) patients and to describe the diagnostic performance of SpO2 in detecting low SaO2 and PaO2. A paired SpO2/SaO2 measurement was obtained from 404 adults in ICU. Measurements were used to calculate bias, precision, and limits of agreement. Associations between bias and variables including vasopressor and inotrope use, capillary refill time, hand temperature, pulse pressure, body temperature, oximeter model, and skin colour were estimated. There was no overall statistically significant bias in paired SpO2/SaO2 measurements; observed limits of agreement were +/-4.4%. However, body temperature, oximeter model, and skin colour, were statistically significantly associated with the degree of bias. SpO2 <89% had a sensitivity of 3/7 (42.9%; 95% confidence intervals, CI, 9.9% to 81.6%) and a specificity of 344/384 (89.6%; 95% CI 86.1% to 92.5%) for detecting SaO2 <89%. The absence of statistically significant bias in paired SpO2/SaO2 in adult ICU patients provides support for the use of pulse oximetry to titrate oxygen therapy. However, SpO2 recordings alone should be used cautiously when SaO2 recordings of 4.4% higher or lower than the observed SpO2 would be of concern. A range of variables relevant to the critically ill had little or no effect on bias.

The relationship between maternal self-efficacy, compliance and outcome in a trial of vitamin D supplementation in pregnancy

In a randomised controlled trial of vitamin D during pregnancy, we demonstrated that women with lower self-efficacy were more likely to experience practical problems with taking the trial medication and that this was associated with lower compliance and achieved 25(OH)-vitamin D concentrations.

INTRODUCTION

The relationship between self-efficacy (the belief that one can carry out a behaviour), compliance with study protocol and outcome was explored within a randomised, double-blind, placebo-controlled trial of vitamin D supplementation in pregnancy.

METHODS

In the Maternal Vitamin D Osteoporosis Study (MAVIDOS) trial, women with circulating plasma 25(OH)-vitamin D of 25-100 nmol/l in early pregnancy were randomised to either 1000 IU cholecalciferol/day or matched placebo from 14 weeks until delivery. Circulating 25(OH)-vitamin D concentrations were assessed at 14 and 34 weeks' gestation. A sequential sub-sample completed Schwarzer's General Self-Efficacy Scale at 14 and 34 weeks and the Problematic Experiences of Therapy Scale at 34 weeks. Women were interviewed about their experiences of the trial and interview transcripts analysed thematically.

RESULTS

In 203 women, those with higher self-efficacy were less likely to experience practical problems taking the study medication (odds ratio (OR) 0.81 (95 % confidence interval (CI) 0.69-0.95), p = 0.01). Over half reported practical problems associated with poorer compliance with the protocol requiring women to take the medication daily. Compliance in women who experienced practical problems was 94 % compared with 98 % for those with no problems (p < 0.001). Poorer compliance was also associated with lower concentrations of 25(OH)-D in late pregnancy in the treatment group (β = 0.54 nmol/l (95 % CI 0.18-0.89), p = 0.003). Thematic analysis suggested common difficulties were remembering to take the medication every day and swallowing the large capsules.

CONCLUSIONS

These findings suggest that differences in self-efficacy influence trial outcomes. Such information may help clinicians anticipate responses to routine vitamin D supplementation in pregnancy and identify those who may need more support to comply.

TRIAL REGISTRATION

ISRCTN82927713, registered 11/04/2008.

Preconception and pregnancy: opportunities to intervene to improve women's diets and lifestyles

Recently, large-scale trials of behavioural interventions have failed to show improvements in pregnancy outcomes. They have, however, shown that lifestyle support improves maternal diet and physical activity during pregnancy, and can reduce weight gain. This suggests that pregnancy, and possibly the whole periconceptional period, represents a 'teachable moment' for changes in diet and lifestyle, an idea that was made much of in the recent report of the Chief Medical Officer for England. The greatest challenge with all trials of diet and lifestyle interventions is to engage people and to sustain this engagement. With this in mind, we propose a design of intervention that aims simultaneously to engage women through motivational conversations and to offer access to a digital platform that provides structured support for diet and lifestyle change. This intervention design therefore makes best use of learning from the trials described above and from recent advances in digital intervention design.

Subunit organization of a synechocystis hetero-oligomeric thylakoid FtsH complex involved in photosystem II repair

FtsH metalloproteases are key components of the photosystem II (PSII) repair cycle, which operates to maintain photosynthetic activity in the light. Despite their physiological importance, the structure and subunit composition of thylakoid FtsH complexes remain uncertain. Mutagenesis has previously revealed that the four FtsH homologs encoded by the cyanobacterium Synechocystis sp PCC 6803 are functionally different: FtsH1 and FtsH3 are required for cell viability, whereas FtsH2 and FtsH4 are dispensable. To gain insights into FtsH2, which is involved in selective D1 protein degradation during PSII repair, we used a strain of Synechocystis 6803 expressing a glutathione S-transferase (GST)-tagged derivative (FtsH2-GST) to isolate FtsH2-containing complexes. Biochemical analysis revealed that FtsH2-GST forms a hetero-oligomeric complex with FtsH3. FtsH2 also interacts with FtsH3 in the wild-type strain, and a mutant depleted in FtsH3, like ftsH2(-) mutants, displays impaired D1 degradation. FtsH3 also forms a separate heterocomplex with FtsH1, thus explaining why FtsH3 is more important than FtsH2 for cell viability. We investigated the structure of the isolated FtsH2-GST/FtsH3 complex using transmission electron microscopy and single-particle analysis. The three-dimensional structural model obtained at a resolution of 26 Å revealed that the complex is hexameric and consists of alternating FtsH2/FtsH3 subunits.

Low levels of food involvement and negative affect reduce the quality of diet in women of lower educational attainment

BACKGROUND

Women of lower educational attainment tend to have poorer quality diets and lower food involvement (an indicator of the priority given to food) than women of higher educational attainment. The present study reports a study of the role of food involvement in the relationship between educational attainment and quality of diet in young women.

METHODS

The first phase uses six focus group discussions (n = 28) to explore the function of food involvement in shaping the food choices of women of lower and higher educational attainment with young children. The second phase is a survey that examines the relationship between educational attainment and quality of diet in women, and explores the role of mediating factors identified by the focus group discussions.

RESULTS

The focus groups suggested that lower food involvement in women of lower educational attainment might be associated with negative affect (i.e. an observable expression of negative emotion), and that this might mean that they did not place a high priority on eating a good quality diet. In support of this hypothesis, the survey of 1010 UK women found that 14% of the effect of educational attainment on food involvement was mediated through the woman's affect (P ≤ 0.001), and that 9% of the effect of educational attainment on quality of diet was mediated through food involvement (P ≤ 0.001).

CONCLUSIONS

Women who leave school with fewer qualifications may have poorer quality diets than women with more qualifications because they tend to have a lower level of food involvement, partly attributed to a more negative affect. Interventions to improve women's mood may benefit their quality of diet.

[Interferon-gamma release assays for hospital-based tuberculosis diagnostics in children and adolescents--a retrospective analysis]

OBJECTIVE

Interferon-gamma release assays (IGRA) are well established for diagnosing latent tuberculosis infection in adults. Evidence for their diagnostic relevance in children is still insufficient. The aim of this study was to evaluate the sensitivity and specificity of IGRA compared to the tuberculin skin test (TST) in a local population of children and adolescents presenting to our lung clinic with a specialised outpatient department.

METHODS

Records from all patients evaluated for tuberculosis at our centre between 2009 and 2011 were analysed retrospectively. Complete data sets were available for 80 children and adolescents (age 3 months to 17 years) in the following diagnostic groups: active pulmonary tuberculosis (MTB, n = 13), latent tuberculosis infection (LTBI, n = 15) and controls with tuberculosis exposure (n = 40), non-tuberculous mycobacterial disease (NTM, n = 2) or other lung diseases (n = 10).

RESULTS

All 13 patients with MTB were positive on both IGRA and TST. Among the LTBI patients, 14 /15 had a positive IGRA and 14 /15 a positive TST result. In the control group 0 /52 exceeded the IGRA cut-off, while three patients had a positive TST due to a cross reaction with BCG or NTM.

DISCUSSION

IGRA and TST results are highly correlated in paediatric patients with active or latent tuberculosis. IGRA sensitivity was comparable to that of the TST with a higher specificity as expected. The importance of IGRA in the hospital setting to guide diagnostic algorithms in an unselected population should be further evaluated in prospective studies.

Subchronic Oral Toxicity Study of Furan in B6C3F1 Mice

Furan is a heterocyclic organic compound formed during heat treatment for processing and preservation of various types of food. Rodent studies have previously shown that furan is a hepatocarcinogen. Those studies were conducted over a high dose range, which induced tumors at nearly 100% incidence at all doses. This ninety-day gavage study in mice was conducted to extend the dose to a lower range (0.0, 0.03, 0.12, 0.5, 2.0, and 8.0 mg/kg body weight [bw] per day) to identify a no-observed adverse effect level for hepatotoxicity and to characterize non-neoplastic effects, including those affecting clinical biochemistry, hematology, tissue morphology, and histopathology. The liver was the primary target organ with dose-dependent toxicity. Liver weights were increased at the 8.0 mg/kg bw dose in females only. Levels of the serum enzyme alanine transaminase, representative of liver damage, were increased three-fold at the highest dose. Histological changes in the liver were observed at 2.0 and 8.0 mg/kg bw in both sexes. Although clinical parameters were also altered for the kidney, these differences were not accompanied by histological changes. Based on these clinical biochemical and histological changes, a no-observed adverse effect level of 0.12 mg/kg bw per day of furan in mice is suggested.

Subchronic Oral Toxicity Study of Furan in Fischer-344 Rats

Rodent studies have shown that furan is a hepatocarcinogen. Previous studies conducted with high doses showed tumors at nearly 100% incidence at all doses. In this paper, a ninety-day gavage experiment conducted with lower doses (0.0, 0.03, 0.12, 0.5, 2.0, and 8.0 mg/kg bw) to identify a no-observed adverse effect level for hepatotoxicity and to characterize non-neoplastic effects including gross changes and histopathology, clinical biochemistry, hematology, and immunotoxicology is reported. As indicated by changes in serum biomarkers, increased liver weights and gross and histological lesions, the liver is the major target organ affected by furan. There were no changes in body weights, food consumption, or histology in other organs. Some of the serum electrolyte markers, including phosphorus, were altered. There was a significant increase in serum thyroxine and triidothyronine in males. This increase was not accompanied by histological thyroid changes. Immunophenotypic analysis showed that thymic lymphocyte maturation was altered in male rats. Although altered clinical biochemistry and hematological parameters were observed at a dose of > 0.5 mg/kg bw, mild histological lesions in the liver were observed at > 0.12 mg/kg bw. Based on this finding, a furan dose of 0.03 mg/kg bw was proposed as the no-observed adverse effect level for hepatic toxicity.

Identification and pathogenicity to rainbow trout, Oncorhynchus mykiss (Walbaum), of some aeromonads

Twelve strains of fish pathogenic aeromonads were identified by 16S rRNA sequencing as Aeromonas bestiarum, A. hydrophila, A. hydrophila subsp. dhakensis, A. salmonicida subsp. salmonicida, A. sobria biovar sobria and A. veronii biovar sobria. Following intramuscular injection, A. hydrophila subsp. dhakensis caused dark liquefying, raised furuncle-like lesions in rainbow trout within 48 h. Extracellular products of all cultures contained gelatinase and lecithinase, and most revealed lipase. Congo red absorption and siderophore production was recorded, but not so the suicide phenomenon or slime production. Sodium dodecyl sulphate polyacrylamide gel electrophoresis profile of the outer membrane proteins (OMP) revealed 10-25 bands, of which major bands were seen in the region of 32.5-47.5 and 62-83 kDa. Marked heterogenicity of the OMP and whole cell protein (WCP) profiles within and among the species was observed. Polypeptides of 83-173 kDa were detected in the WCP profile of the cultures, but they were not expressed in OMP fractions.

Pediatric multidetector computed tomography using tube current modulation and a patient image gallery

BACKGROUND

Dose reduction is crucial in pediatric multidetector computed tomography (MDCT).

PURPOSE

To perform pediatric 16-slice MDCT using tube current modulations and to adjust prospectively the tube current using a patient image gallery (IG) providing simulated dose-reduced protocols; and to evaluate and compare the image quality of the IG and the clinical MDCT.

MATERIAL AND METHODS

30 examinations (thorax, n = 15; abdomen, n = 8; pelvis, n = 7) in 20 patients (nine male, age 8.05 +/- 7.33 years, weight 29.8 +/- 24.02 kg) were performed according to an IG on a 16-slice MDCT with additional use of online tube current modulation (CARE Dose). Three radiologists visually assessed image quality from the IG and actual 16-slice MDCT scans. For objective analysis, image noise was determined.

RESULTS

Statistical analysis showed moderate concordance in objective (K = 0.68-0.78) and subjective (K = 0.33-0.64) image assessment between the IG and clinical 16-slice MDCT scans. Depending on the weight group and clinical question, no or only minor dose reductions in the chest, but moderate to considerable reductions in the abdominal/pelvic 16-slice MDCT scans compared to previously used pediatric protocols were achieved. Extra dose reduction was achieved due to additional use of CARE Dose depending on age group and scan region (mean 8.6-23.9%).

CONCLUSION

The IG enabled us to prospectively reduce the tube current and adapt the required image quality to the clinical question. Additional dose reduction was achieved with application of CARE Dose; nevertheless, the images are comparable to the simulated images of the IG.

Community participation in primary health care projects of the Muldersdrift Health and Development Programme

After numerous teething problems (1974-1994), the Department of Nursing Education of WITS University took responsibility for the Muldersdrift Health and Development Programme (MHDP). The nursing science students explored and implemented an empowerment approach to community participation. The students worked with MHDP health workers to improve health through community participation, in combination with primary health care (PHC) activities and the involvement of a variety of community groups. As the PHC projects evolved overtime, the need arose to evaluate the level of community participation and how much community ownership was present over decision-making and resources. This led to the question “What was the level of community participation in PHC projects of the MHDP?” Based on the question the following objectives were set, i.e. i) to evaluate the community participation in PHC initiatives; ii) to provide the project partners with motivational affirmation on the level of community participation criteria thus far achieved; iii) to indicate to participants the mechanisms that should still be implemented if they wanted to advance to higher levels of community participation; iv) to evaluate the MHDP’s implementation of a people-centred approach to community participation in PHC; and v) the evaluation of the level of community participation in PHC projects in the MHDP. An evaluative, descriptive, contextual and quantitative research design was used. Ethical standards were adhered to throughout the study. The MHDP had a study population of twentythree (N=23) PHC projects. A purposive sample of seven PHC initiatives was chosen according to specific selection criteria and evaluated according to the “Criteria to evaluate community participation in PHC projects” instrument (a quantitative tool). Structured group interviews were done with PHC projects’ executive committee members. The Joint Management Committee’s data was collected through mailed self-administered questionnaires. Validity and reliability were ensured according to strict criteria. Thereafter results were analysed and plotted on a radiating arm continuum. The following factors had component scores: organization, leadership, resources, management; needs and skills. A spider graph was produced after each factor’s continuum was connected in a spoke figuration that brought them together at the base where participation was at its most narrow. The results are presented and a graph and discussion is provided on each of the PHC projects.

The role of the FtsH and Deg proteases in the repair of UV-B radiation-damaged Photosystem II in the cyanobacterium Synechocystis PCC 6803

The photosystem two (PSII) complex found in oxygenic photosynthetic organisms is susceptible to damage by UV-B irradiation and undergoes repair in vivo to maintain activity. Until now there has been little information on the identity of the enzymes involved in repair. In the present study we have investigated the involvement of the FtsH and Deg protease families in the degradation of UV-B-damaged PSII reaction center subunits, D1 and D2, in the cyanobacterium Synechocystis 6803. PSII activity in a DeltaFtsH (slr0228) strain, with an inactivated slr0228 gene, showed increased sensitivity to UV-B radiation and impaired recovery of activity in visible light after UV-B exposure. In contrast, in DeltaDeg-G cells, in which all the three deg genes were inactivated, the damage and recovery kinetics were the same as in the WT. Immunoblotting showed that the loss of both the D1 and D2 proteins was retarded in DeltaFtsH (slr0228) during UV-B exposure, and the extent of their restoration during the recovery period was decreased relative to the WT. However, in the DeltaDeg-G cells the damage and recovery kinetics of D1 and D2 were the same as in the WT. These data demonstrate a key role of FtsH (slr0228), but not the Deg proteases, for the repair of PS II during and following UV-B radiation at the step of degrading both of the UV-B damaged D1 and D2 reaction center subunits.

Extensive DNA methylation in normal colorectal mucosa in hyperplastic polyposis

BACKGROUND

Hyperplastic polyposis of the colorectum is a precancerous condition that has been linked with DNA methylation. The polyps in this condition have been distinguished from typical small hyperplastic polyps and renamed sessile serrated adenomas. Sessile serrated adenomas also occur sporadically and appear to be indistinguishable from their counterparts in hyperplastic polyposis.

AIMS AND METHODS

The existence of distinguishing molecular features was explored in a series of serrated polyps and matched normal mucosa from patients with and without hyperplastic polyposis by assessing mutation of BRAF, DNA methylation in 14 markers (MINTs 1, 2 and 31, p16, MGMT, MLH1, RASSF1, RASSF2, NORE1 (RASSF5), RKIP, MST1, DAPK, FAS, and CHFR), and immunoexpression of MLH1.

RESULTS

There was more extensive methylation in sessile serrated adenomas from subjects with hyperplastic polyposis (p<0.0001). A more clearcut difference in patients with hyperplastic polyposis was the finding of extensive DNA methylation in normal mucosa from the proximal colon.

CONCLUSIONS

A genetic predisposition may underlie at least some forms of hyperplastic polyposis in which the earliest manifestation may be hypermethylation of multiple gene promoters in normal colorectal mucosa. Additionally, some of the heterogeneity within hyperplastic polyposis may be explained by different propensities for MLH1 inactivation within polyps.

Advanced colorectal polyps with the molecular and morphological features of serrated polyps and adenomas: concept of a 'fusion' pathway to colorectal cancer

AIM

To establish and explain the pattern of molecular signatures across colorectal polyps.

METHODS AND RESULTS

Thirty-two sessile serrated adenomas (SSA), 10 mixed polyps (MP), 15 traditional serrated adenomas (SA), 49 hyperplastic polyps (HP) and 84 adenomas were assessed for mutation of KRAS and BRAF and aberrant expression of p53. The findings were correlated with loss of expression of O-6-methylguanine DNA methyltransferase (MGMT). KRAS mutation occurred more frequently (26.5%) than BRAF mutation (4.8%) in adenomas (P < 0.001) and particularly in adenomas with villous architecture (50%). Loss of expression of MGMT correlated with KRAS mutation in small tubular adenomas (P < 0.04). BRAF mutation was frequent in HPs (67%) and SSAs (81%), while KRAS mutation was infrequent (4% and 3%, respectively). Of MPs and SAs, 72% had either BRAF or KRAS mutation. Aberrant expression of p53 was uncommon overall, but occurred more frequently in MPs and SAs (12%) than adenomas (1%) (P < 0.04) and there was concordant loss of expression of MGMT.

CONCLUSIONS

Molecular alterations that are characteristic of the serrated pathway and adenoma-carcinoma sequence can co-occur in a minority of advanced colorectal polyps that then show morphological features of both pathways. These lesions account for only 2% of colorectal polyps, but may be relatively aggressive.

The deg proteases protect Synechocystis sp. PCC 6803 during heat and light stresses but are not essential for removal of damaged D1 protein during the photosystem two repair cycle

Members of the DegP/HtrA (or Deg) family of proteases are found widely in nature and play an important role in the proteolysis of misfolded and damaged proteins. As yet, their physiological role in oxygenic photosynthetic organisms is unclear, although it has been widely speculated that they participate in the degradation of the photodamaged D1 subunit in the photosystem two complex (PSII) repair cycle, which is needed to maintain PSII activity in both cyanobacteria and chloroplasts. We have examined the role of the three Deg proteases found in the cyanobacterium Synechocystis sp. PCC 6803 through analysis of double and triple insertion mutants. We have discovered that these proteases show overlap in function and are involved in a number of key physiological responses ranging from protection against light and heat stresses to phototaxis. In previous work, we concluded that the Deg proteases played either a direct or an indirect role in PSII repair in a glucose-tolerant version of Synechocystis 6803 (Silva, P., Choi, Y. J., Hassan, H. A., and Nixon, P. J. (2002) Philos. Trans. R. Soc. Lond. B Biol. Sci. 357, 1461-1467). In this work, we have now been able to demonstrate unambiguously, using a triple deg mutant created in the wild type strain of Synechocystis 6803, that the Deg proteases are not obligatory for PSII repair and D1 degradation. We therefore conclude that although the Deg proteases are needed for photoprotection of Synechocystis sp. PCC 6803, they do not play an essential role in D1 turnover and PSII repair in vivo.

Why are rural Indian women so thin? Findings from a village in Maharashtra

OBJECTIVE

To identify social, behavioural and cultural factors that explain the thinness of young women relative to their men in rural Maharashtra, India.

DESIGN

Twelve focus group discussions were conducted to explore the villagers' understanding of why women in their area might be thinner than men.

SETTING

Pabal village and surrounding hamlets, in the Pune district of Maharashtra, India.

SUBJECTS

Samples of young mothers and fathers, grandmothers and grandfathers were selected from families in the village with children below 10 years of age.

RESULTS

Four factors were identified that the villagers felt contributed to the disparity in thinness. First, marriage isolated girls from their own families and villages, and brought the expectation of early motherhood. Young brides were often unable to relax and eat adequately. Second, marriage increased the workload of young women. They were expected to do the heaviest household chores as well as farm work in this predominantly agricultural community. Third, women had no financial autonomy or freedom of movement, and were therefore denied access to supplementary food sources available to men. Fourth, young women felt responsible for their household's health and success. They were encouraged to fast regularly to ensure this. Despite feeling responsible, young women had no control over factors that might affect the household's well being. This made them anxious and worried a great deal of the time.

CONCLUSIONS

Interventions to improve the nutritional status of young women in this region need to recognise the roles and responsibilities taken up by young brides.

Outbreak of low pathogenicity H7N3 avian influenza in UK, including associated case of human conjunctivitis

On 26 April 2006, the veterinary authorities in the United Kingdom reported that there had been an outbreak of avian influenza type A/H7 among a 35 000-bird housed poultry flock in eastern England, United Kingdom.

Volatile organic compounds in the exhaled breath of young patients with cystic fibrosis

Inflammatory mediators in the exhaled breath are receiving growing medical interest as noninvasive disease markers. Volatile organic compounds have been investigated in this context, but clinical information and methodological standards are limited. The levels of ethane, propane, n-pentane, methanol, ethanol, 2-propanol, acetone, isoprene, benzene, toluene, dimethyl sulphide (DMS) and limonene were measured in repeated breath samples from 20 cystic fibrosis patients and 20 healthy controls (aged 8-29 yrs). Three end-exhaled and one ambient air sample were collected per person and analysed on a customised gas chromatography system. Intra-subject coefficients of variation ranged between 9 and 34%, and hydrocarbon breath levels were influenced by their inspired concentrations. The alveolar gradient for pentane was higher in cystic fibrosis patients than in healthy controls (0.36 versus 0.21 ppb) and inversely proportional to forced expiratory volume in one second; highest values were observed in patients with pulmonary exacerbations (0.73 versus 0.24 ppb). Cystic fibrosis patients also exhibited a lower output of DMS (3.9 versus 7.6 ppb). Group differences were not significant for ethane and the remaining substances. It was concluded that chemical breath analysis for volatile organic compounds is feasible and may hold potential for the noninvasive diagnosis and follow-up of inflammatory processes in cystic fibrosis lung disease.