SVEP1 influences monocyte to macrophage differentiation via integrin α4β1/α9β1 and Rho/Rac signalling

BACKGROUND

The large extracellular matrix protein SVEP1 mediates cell adhesion via integrin α9β1. Recent studies have identified an association between a missense variant in SVEP1 and increased risk of coronary artery disease (CAD) in humans and in mice Svep1 deficiency alters the development of atherosclerotic plaques. However how SVEP1 functionally contributes to CAD pathogenesis is not fully understood. Monocyte recruitment and differentiation to macrophages is a key step in the development of atherosclerosis. Here, we investigated the requirement for SVEP1 in this process.

METHODS

SVEP1 expression was measured during monocyte-macrophage differentiation in primary monocytes and THP-1 human monocytic cells. SVEP1 knockout THP-1 cell lines and the dual integrin α4β1/α9β1 inhibitor, BOP, were utilised to investigate the effect of these proteins in THP-1 cell adhesion, migration and cell spreading assays. Subsequent activation of downstream integrin signalling intermediaries was quantified by western blotting.

RESULTS

SVEP1 gene expression increases in monocyte to macrophage differentiation in human primary monocytes and THP-1 cells. Using two SVEP1 knockout THP-1 cells we observed reduction in monocyte adhesion, migration, and cell spreading compared to control cells. Similar results were found with integrin α4β1/α9β1 inhibition. We demonstrate reduced activity of Rho and Rac1 in SVEP1 knockout THP-1 cells.

CONCLUSIONS

SVEP1 regulates monocyte recruitment and differentiation phenotypes through an integrin α4β1/α9β1 dependent mechanism.

GENERAL SIGNIFICANCE

These results describe a novel role for SVEP1 in monocyte behaviour relevant to CAD pathophysiology.

Progressive resistance training in young people with Prader-Willi syndrome: protocol for a randomised trial (PRESTO)

INTRODUCTION

Preliminary evidence suggests that progressive resistance training may be beneficial for people with Prader-Willi Syndrome (PWS), a rare genetic condition that results in muscle weakness and low muscle tone.To establish whether community-based progressive resistance training is effective in improving the muscle strength of people with PWS; to determine cost-effectiveness; and, to complete a process evaluation assessing intervention fidelity, exploring mechanisms of impact, understanding participant experiences and identifying contextual factors affecting implementation.

METHODS AND ANALYSIS

A multisite, randomised controlled trial will be completed. Sixty participants with PWS will be randomised to receive either progressive resistance training (experimental) or non-progressive exercise (placebo control). Participants will be aged 13 to 60 years, be able to follow simple instructions in English and have no contraindications to performing progressive resistance training. The experimental group will complete progressive resistance training two times weekly for 24 weeks supervised by an exercise professional at a community gym. The control group will receive all aspects of the intervention except progressive overload. Outcomes will be assessed at week 25 (primary endpoint) and week 52 by a blinded assessor. The primary outcome is muscle strength assessed using one repetition maximum for upper limb and lower limb. Secondary outcomes are muscle mass, functional strength, physical activity, community participation, health-related quality of life and behaviour. Health economic analysis will evaluate cost-effectiveness. Process evaluation will assess safety and intervention fidelity, investigate mechanism of impact, explore participant experiences and identify contextual factors affecting implementation. Data collection commenced in February 2020 and will conclude in September 2023.

ETHICS AND DISSEMINATION

Ethical approval was obtained from The Royal Children's Hospital Human Research Ethics Committee (HREC/50874/RCHM-2019) under the National Mutual Acceptance initiative. Research governance approvals were obtained from five clinical sites. Results will be disseminated through published manuscripts, conference presentations, public seminars and practical resources for stakeholder groups.

TRIAL REGISTRATION NUMBER

ACTRN12620000416998; Australian and New Zealand Clinical Trial Registry.

1020 Delay to Surgery in Acute Perforated and Ischaemic Gastrointestinal Pathology

Introduction

Patients with acute abdominal pathology requiring emergency laparotomy who experience a delay to theatre have an increased risk of morbidity, mortality, and complications. The timeline between symptom onset and operation is ill-defined with international variance in assessment and management. This systematic review aims to define where delays to surgery occur and assess the evidence for previous interventions.

Method

A systematic review was performed searching MEDLINE and EMBASE databases (January 1st 2005 to May 6th 2020). All studies assessing the impact of time to theatre in patients with acute abdominal pathology requiring emergency laparotomy were considered.

Results

Eighty-five results were assessed to include 19 papers in the analysis. Fifteen unique timepoints were identified in the patient pathway between symptom onset and operation which could be classified into four distinct phases. Time from admission to theatre (1 to 72 hours), and mortality rate (10.6-74.5%) varied greatly between studies. Mean time to surgery was significantly higher in deceased patients compared to survivors. Delays were related to imaging, diagnosis, decision-making, theatre availability and staffing. Four of five interventional studies showed a reduced mortality following introduction of an acute laparotomy pathway.

Conclusions

There is wide variation in the definition and measurement of time delays prior to emergency surgery with few studies exploring interventions. Given the heterogenous nature of the patient population and pathologies, an assessment and management framework from onset of symptoms to operation is proposed. This could be incorporated into national mortality prediction and audit tools and assist in the assessment of interventions.

1308 Investigating the Use of a Novel Pre-Hospital Triage Tool for Acute Abdominal Surgical Emergencies – A Two-Phase Single Centre Cohort Study

Background

Despite the recent improvements in mortality in patients undergoing emergency laparotomy(EL) within the UK, delay to theatre continues to be associated with increased mortality. This study aimed to assess if patients requiring urgent surgical intervention for acute abdominal surgical pathology could be identified in the pre-hospital setting.

Method

A two-phase, single-centre, cohort study was performed. Phase 1 retrospectively investigated patients who underwent emergency laparotomy between 01/01/2019-31/12/2019 at Leeds Teaching Hospital Trust (LTHT) through the NELA database. Phase 2 prospectively assessed NEWS2 for all patients presenting to LTHT Surgical Admissions Unit with abdominal pain between 01/01/2020-31/01/2020.

Results

Phase 1: 45 patients were coded through NELA and confirmed through operation note review as undergoing EL for gastrointestinal perforation. 66%(n = 30) were assessed by the ambulance service and 80% (n = 24) had a NEWS2 of 3 or greater. Phase 2: 319 patients were assessed in SAU/ED, of which 69 initially treated by the ambulance service. 30% (n = 21) of these patients had an initial NEWS2 of 3 or above. Sensitivity of a NEWS2 score of >/3 in predicting the need for immediate surgical intervention including EL was 95%(95%CI, 74-99) and specificity was 95% (95%CI, 83-99) with a PPV of 86%(95%CI 67-95) and NPV of 98% (95%CI, 87-99).

Conclusions

A NEWS2 score of >/3 predicts the need for emergency surgical intervention including laparotomy for gastrointestinal perforation with reasonable sensitivity in this cohort. A pre-hospital triage tool for patients presenting with abdominal pain could utilise NEWS2 as an adjunct to decision-making in an acute abdominal pathway.

1161 Streamlining the Patient Journey for Operative Management During COVID 19

Aim

Leeds, UK is a high-volume acute surgery unit. Emergency operating was drastically affected by the pandemic and time from admission to definitive procedure significantly increased. This intervention aimed to streamline the patient journey from acute admission to the operating theatre.

Method

An audit considering delays to transfer, theatre access and recovery discharge, along with the criteria used for ‘Hot’ theatre was undertaken. Data was collected prospectively between 02/06/2020-06/07/2020 via a standardised proforma. Preliminary results suggested a geographically remote ‘hot’ theatre was associated with multi-factorial delays so was relocated to more familiar surroundings. This was re-audited between 06/07/2020-06/08/2020 aiming to characterise factors contributing to delay. A dedicated in-hours acute theatres porter was introduced for a trial period. Data was collected retrospectively between 24/08/2020-14/09/2020 and prospectively between 14/09-05/10/2020 via hospital electronic systems.

Results

Initially the average time from patient transfer to leaving theatre recovery was 4h6m55s (N = 52). Relocating theatres reduced this to 2h48m04s (N = 74)- an average reduction of 1h18m51s. The greatest reduction was seen in anaesthetic time between 1h17m54s to 41m29s. The introduction of a dedicated porter reduced the average transfer time to theatre from 36 minutes (N = 53) to 21 minutes (N = 68) (p < 0.05).

Conclusions

Delay to theatre has a high cost financially and in its effect on patient outcomes. Delays are often multifactorial and robust systems are essential to minimise delays. Patients are best served by well-trained, dedicated ‘Acute’ team in familiar surroundings. Long-term implementation of dedicated portering service will save time, money and improve patient care.

1404 NELA Risk Mortality Scores from Admission to Theatre in Emergency Gastrointestinal Perforation – A Retrospective Cohort Study

Background

Patients with acute abdominal pathology requiring emergency laparotomy who experience a delay to theatre have an increased risk of morbidity, mortality and complications. The aim of this study was to assess delay, from symptom onset to theatre in patients with gastrointestinal perforation and its effect on perioperative risk.

Method

A single-centre retrospective study was performed in the Leeds Trust Hospitals, UK investigating the NELA database for patients requiring emergency laparotomy for perforated gastrointestinal viscus who presented to the acute surgical unit or emergency department between 1st February 2018 and 31st January 2020.

Results

101 patients met the inclusion criteria (47% F and 53% M), mean age 59 [21-91]. 37% of patients’ NELA scores worsened from admission to pre-op (median change of + 5.9% IQR 1.3-11.5]), 14% stayed the same and 49% improved (median change of -4.4%[IQR 0.4-9.1]) 3% had their NELA score documented at the time of consent. 18% did not wait for a CT report or went straight to theatre. Mean time from admission to scan report was 9.3 hours (0.9-22.0). Median time from symptom onset to presentation (2 days [IQR 1-13]) was greater in patients with an Index of Multiple Deprivation Decile of 1-5, (n = 64, median 2 days [IQR 1-6]) compared to those in deciles 6-10, (n = 37, median 1 day[IQR 1-3]), p = 0.097.

Conclusions

NELA mortality risk score changes from presentation to surgery in patients with acute gastrointestinal perforation requiring emergency laparotomy. There is suggestion that delay in symptom onset to presentation may correlate with Index of Multiple Deprivation Decile.

Associations Between Hyperphagia, Symptoms of Sleep Breathing Disorder, Behaviour Difficulties and Caregiver Well-Being in Prader-Willi Syndrome: A Preliminary Study

Prader-Willi syndrome (PWS) is a rare genetic disorder characterised by neurodevelopmental delays, hyperphagia, difficulties with social communication and challenging behaviours. Individuals require intensive supervision from caregivers which may negatively affect caregiver quality of life. This study used data collected in the Australasian PWS Registry (n = 50, mean age 11.2 years) to evaluate associations between child behaviours and caregiver mental well-being. Symptoms of sleep-related breathing disorder, child depression and social difficulties were associated with poorer caregiver mental and physical well-being. Growth hormone therapy use was associated with better caregiver mental and physical well-being. Optimising management of problematic behaviours and sleep disturbances have the potential to support caregivers who are the most vital network of support for individuals affected by PWS.

Delay to surgery in acute perforated and ischaemic gastrointestinal pathology: a systematic review

BACKGROUND

Patients with acute abdominal pathology requiring emergency laparotomy who experience a delay to theatre have an increased risk of morbidity, mortality and complications. The timeline between symptom onset and operation is ill defined with international variance in assessment and management. This systematic review aims to define where delays to surgery occur and assess the evidence for interventions trialled across Europe.

METHODS

A systematic review was performed searching MEDLINE and EMBASE databases (1 January 2005 to 6 May 2020). All studies assessing the impact of time to theatre in patients with acute abdominal pathology requiring emergency laparotomy were considered.

RESULTS

Sixteen papers, involving 50 653 patients, were included in the analysis. Fifteen unique timepoints were identified in the patient pathway between symptom onset and operation which are classified into four distinct phases. Time from admission to theatre (1-72 hours) and mortality rate (10.6-74.5 per cent) varied greatly between studies. Mean time to surgery was significantly higher in deceased patients compared with that in survivors. Delays were related to imaging, diagnosis, decision making, theatre availability and staffing. Four of five interventional studies showed a reduced mortality rate following introduction of an acute laparotomy pathway.

CONCLUSION

Given the heterogeneous nature of the patient population and pathologies, an assessment and management framework from onset of symptoms to operation is proposed. This could be incorporated into mortality prediction and audit tools and assist in the assessment of interventions.

Using a trauma informed practice framework to enhance understanding of and identify support strategies for behavioural difficulties in young people with Prader-Willi syndrome

BACKGROUND

Behavioural support for young people with Prader-Willi syndrome (PWS) is necessary in home and school environments. The Trauma Informed Practice (TIP) framework has been used to support young people with complex behavioural needs in school settings.

AIMS

To identify parent and professional perspectives on behavioural challenges experienced by young people with PWS and strategies for supports, to inform understanding of how they are aligned with the TIP framework.

METHOD

Semi-structured interviews were conducted with eight families with a 12-21 year old child with PWS, four clinicians and two teachers to investigate the contexts and mechanisms associated with challenging, calm and productive behaviours. Data were analysed using directed content analysis, using TIP principles as a framework.

RESULTS

Strategies to support young people with PWS aligned with the four overarching TIP Principles:Empowerment, voice and choice; Creating safe environments; Creating a collaborative environment; and Trustworthiness and transparency. Additional Novel domains included: Behavioural underpinnings, Modifying environments and Supporting family capacity.

CONCLUSION

These novel domains can be used to supplement the TIP framework for guidance on how to support young people with PWS.

HEALTH IMPLICATIONS

Development and implementation of strategies to reduce behavioural difficulties in young people with PWS through positive support mechanisms could improve function and social engagement within their families and communities.

Benefits of powered standing wheelchair devices for adolescents with Duchenne muscular dystrophy in the first year of use

AIM

Poorer physical and mental health often accompany loss of walking in Duchenne muscular dystrophy. This study assessed the impacts of powered wheelchair standing device (PWSD) use on muscle and joint pain, joint angles when standing and mental health in adolescents with Duchenne muscular dystrophy.

METHODS

Fourteen adolescents and parents participated in a stepped wedge design study over 12 months. During a baseline and intervention period, adolescents described pain and mental health, and parents reported their child's mental health. Video data were collected to measure hip, knee and ankle joint angles in the preferred standing position.

RESULTS

Compared with baseline and adjusting for covariates, standing wheelchair use was associated with no change in muscle or joint pain or videoed joint angles in standing. Child-reported Strengths and Difficulties total scores decreased (coefficient -3.1, 95% confidence interval -4.6, -1.5); and parent-reported Personal Adjustment and Role Skills Scale total scores increased (coefficient 7.9, 95% confidence interval 3.3-12.5).

CONCLUSIONS

PWSD use was associated with maintenance of musculoskeletal status and advantages to mental health. Long-term observations are necessary to improve understanding of how to support wellbeing in adolescents with Duchenne muscular dystrophy.

Requirements for improving health and well-being of children with Prader-Willi syndrome and their families

Prader-Willi syndrome (PWS) is a rare genetic condition with multi-system involvement. The literature was reviewed to describe neurodevelopment and the behavioural phenotype, endocrine and metabolic disorders and respiratory and sleep functioning. Implications for child and family quality of life were explored. Challenging behaviours contribute to poorer well-being and quality of life for both the child and caregiver. Recent evidence indicates healthy outcomes of weight and height can be achieved with growth hormone therapy and dietary restriction and should be the current target for all individuals with PWS. Gaps in the literature included therapies to manage challenging behaviours, as well as understanding the effects of growth hormone on respiratory and sleep function. New knowledge regarding the transition of children and families from schooling and paediatric health services to employment, accommodation and adult health services is also needed. Developing a national population-based registry could address these knowledge gaps and inform advocacy for support services that improve the well-being of individuals with PWS and their families.

What does practice development (PD) offer mental health-care contexts? A comparative case study of PD methods and outcomes

Practice development (PD) in mental health nursing has been progressing over the last decade; however, the level and impact of PD activity in the field of mental health remains poorly understood outside localized project impact. More specific reporting and comparative analysis of PD outcomes will improve this situation. In response, this paper presents three case scenarios from work taking place in Australia and New Zealand, as working examples of how PD methodologies have been applied within mental health practice settings. Using a comparative framework that captures the contributing assumptions, practices, processes and conditions imperative to effective PD work within a mental health-care context, three case vignettes are reviewed. The critical question driving this paper is 'what mental health-care services does PD offer in terms of transformational change approaches and the promotion of effective workplace cultures?' Conditions considered necessary for successful PD initiatives within mental health contexts are explored such as how PD converges and diverges with mental health-related theories, plus where and how PD activity best integrates with the specific elements associated with mental health-care provision. The findings are further reviewed in line with reports of PD outcomes from other fields of health care.

Choice architecture as a means to change eating behaviour in self-service settings: a systematic review

The primary objective of this review was to investigate the current evidence base for the use of choice architecture as a means to change eating behaviour in self-service eating settings, hence potentially reduce calorie intake. Twelve databases were searched systematically for experimental studies with predefined choice architecture interventions in the period of June 2011-March 2012. The 12 included studies were grouped according to type of interventions and underwent a narrative synthesis. The evidence indicates that (i) health labelling at point of purchase is associated with healthier food choice, while (ii) manipulating the plate and cutlery size has an inconclusive effect on consumption volume. Finally, (iii) assortment manipulation and (iv) payment option manipulation was associated with healthier food choices. The majority of studies were of very weak quality and future research should emphasize a real-life setting and compare their results with the effect of other more well-established interventions on food behaviour in self-service eating settings.

Autonomic responses to dynamic displays of facial expressions in adolescents and adults with Williams syndrome

The behavioral phenotype characteristic of Williams syndrome (WS) is marked by strong interest in social interaction, manifested in attention to human faces, empathy, approach behavior and social disinhibition, often coexisting with generalized anxiety. Despite their heightened social interest, people with WS show deficits in explicit emotion recognition tasks similar to those of people with other developmental disabilities. In the current study we explored whether individuals with WS show distinctive autonomic responsiveness to social-emotional information, using skin conductance response and heart rate measures. Autonomic activation was investigated in response to facial expressions of emotion in adolescents and adults with WS, compared to age-matched normal controls and to age-, IQ- and language-matched individuals with learning or intellectual disabilities (LID). Overall participants with WS were less electrodermally responsive to dynamically presented face stimuli than the age- and IQ-matched LID group, and showed more heart rate deceleration when viewing emotional faces than the controls. These findings, indicating hypoarousal but increased interest in response to the dynamic presentation of facial emotions in WS, are consistent with the behavioral profile of high approachability toward social stimuli in this population.

Mental Capacity Act 2005--what do doctors know?

The Mental Capacity Act 2005 was partially implemented in April 2007. Doctors should be aware of the Act and what implications it has on their clinical practice. This survey looked at the knowledge of physicians and psychiatrists regarding assessing capacity within the Act by means of a questionnaire. The results showed that 100% of physicians and 70% of the psychiatrists answered questions wrongly in the questionnaire. Also, 97% of physicians and 70% of psychiatrists did not have some aspects of knowledge about capacity. Statistically significant differences in responses between physicians and psychiatrists were in relation to their knowledge of the existence and implementation of the Act. Answers were related to active schizophrenia, weighing up pros and cons, and recent assessment of incapability in relation to being by definition incapable. This study shows that psychiatrists do slightly better in answering questions about the Mental Capacity Act 2005 and about capacity when compared with physicians, however both groups could improve their knowledge. With the full implementation of the Act in October 2007, this study shows the urgency and importance of training in the area of capacity for all doctors.

Detention on a general ward: understanding and applying the law

From April 2007 there will be two acts of parliament that govern the legal detention of patients in hospitahl: the Mental Health Act 1983 and the Mental Capacity Act 2005. This article addresses common questions posed to liaison psychiatrists by hospital doctors: how to legally detain patients on general wards and how these Acts are applied.

Trends, priorities and policy directions in the control of vector-borne diseases in urban environments

The habitats available in urban environments tend to be rather lacking in diversity compared to those in the countryside, and relatively few species are able to exploit them. Those that can, however, often find themselves relatively well provided with food and places to live, and relatively free of competitors and predators. This applies not only to such well-known species as the house-sparrow, but also to most of the important mosquito vectors of human disease in urban areas. Human city dwellers thus tend to be exposed to a different spectrum of disease than their rural counterparts. This review describes how the physical and social changes associated with urbanization have altered the transmission of vector-borne disease. It concentrates on the important mosquito-borne infections: malaria, dengue and filariasis. Dengue virus vectors breed in relatively clean water in man-made containers, while urban filariasis vectors breed in highly polluted water, and these mosquitoes have now been spread by man's activities to almost every tropical city. With important exceptions, anopheline malaria vectors have not generally succeeded in adapting to urban life, but malaria can still be a problem where there are rural pockets in the middle of town. Each of these problems requires control using different technologies and timing. The following policy implications are stressed. The areas of responsibility between different sectors of the local services (health, water supply, sanitation), and between these and the public, need to be clearly defined. Due to the biological complexities of vector-borne disease, decentralized primary health care systems are generally incapable of ensuring that control efforts are adequately targeted in time and space. Community support is essential but specialized technical skills are also required.

Mitochondrial DNA variation of Triatoma infestans populations and its implication on the specific status of T. melanosoma

DNA sequence comparison of 412 base-pairs fragments of the mitochondrial cytochrome B gene was used to infer the genetic structure of nine geographical Triatoma infestans populations and their phylogenetic relationship with T. melanosoma and T. brasiliensis. T. infestans and T. melanosoma were compared by morphometry, allozyme and cytogenetic analyses, as well as subjected to reciprocal crosses, in order to clarify the taxonomic status of the latter. No differences were found to distinguish the two species and the crosses between them yielded progeny. T. infestans populations presented four haplotypes that could be separated in two clusters: one formed by the samples from Bolivia (Andes and Chaco) and the other formed by samples from Argentina and Brazil. Silvatic and domestic T. infestans populations from Bolivia (Andes) were genetically identical.

Trypanosoma cruzi - the vector-parasite paradox

Trypanosoma cruzi and the majority of its insect vectors (Hemiptera, Reduviidae, Triatominae) are confined to the Americas. But while recent molecular studies indicate a relatively ancient origin for the parasite ( approximately 65 million years ago) there is increasing evidence that the blood-sucking triatomine vectors have evolved comparatively recently (<5 mya). This review examines the evidence for these ideas, and attempts to reconcile the apparent paradox by suggesting that marsupial opossums (Didelphidae) may have played a role, not just as original reservoir hosts, but also as original vectors of the parasite.

Intraocular pharmacokinetics and safety of a humanized monoclonal antibody in rabbits after intravitreal administration of a solution or a PLGA microsphere formulation

Poly(lactic-co-glycolic) acid (PLGA) bioresorbable microspheres are used for controlled-release drug delivery and are particularly promising for ocular indications. The objective of the current study was to evaluate the pharmacokinetics and safety of a recombinant human monoclonal antibody (rhuMAb HER2) in rabbits after bolus intravitreal administration of a solution or a PLGA-microsphere formulation. On Day 0, forty-eight male New Zealand white rabbits (2.3-2.6 kg) were immobilized with intramuscular ketamine/xylazine, and the test materials were injected directly into the vitreous compartment. Group 1 animals received rhuMAb HER2 in 50:50 lactide: glycolide PLGA microspheres; Group 2 animals received rhuMAb HER2 in solution (n = 24/group). The dose for each eye was 25 microg (50 microl). After dosing, animals were sacrificed at 2 min, and on 1, 2, 4, 7, 14, 23, 29, 37, 44, 50, and 56 days (n = 2/timepoint/group). Safety assessment included direct ophthalmoscopy, clinical observations, body weight, and hematology and clinical chemistry panels. At necropsy, vitreous and plasma were collected for pharmacokinetics and analysis for antibodies to rhuMAb HER2, and the vitreal pellet (Group 1) was prepared for histologic evaluation. All animals completed the study per protocol-both treatments were well tolerated, and no suppurative or mixed inflammatory cell reaction was observed in the vitreal samples (Group 1) at any of the time points examined. Antibodies to rhuMAb HER2 were detected in plasma samples by Day 7 in both treatment groups, but infrequently in vitreous samples. There were no safety implications associated with this immune response. The in vitro characterization of the PLGA microspheres provided reasonable projections of the in vivo rhuMAb HER2 release kinetics (Group 1). The total amount of antibody that was released was similar in vitro (25.9%) and in vivo (32.4%). RhuMAb HER2 (Group 2) was cleared slowly from the vitreous compartment, with initial and terminal half-lives of 0.9 and 5.6 days, respectively. The volume of distribution approximated the vitreous volume in a rabbit eye.

Changes in the sexual dimorphism of triatominae in the transition from natural to artificial habitats

A shift from large to small average sizes was observed in Triatoma infestans and Rhodnius domesticus between field and domestic (or laboratory) conditions of life. It was more pronounced in the female specimens, leading to a subsequent reduction of sexual size dimorphism. This feature is discussed in terms of genetic and populational changes occurring from natural to artificial habitats, in particular those related to population densities. Sexual size dimorphism is then recommended as a new character to be used in the study of species of Triatominae adapting to domestic ecotopes.

A novel silent posttranslational mechanism converts methionine to aspartate in hemoglobin Bristol (beta 67[E11] Val-Met->Asp)

The first reported case of congenital Heinz body hemolytic anemia was subsequently shown to be caused by an unstable hemoglobin, Hb Bristol [beta 67(E11) Val-Asp]. This has become one of the classic models of an unstable hemoglobin, the hydrophilic aspartate disrupting the hydrophobic heme pocket. We have restudied this original case, who remains clinically well after nearly 50 years of severe hemolysis with a hemoglobin level of about 7 g/dL and two unrelated Japanese cases. Surprisingly, all three cases show the same DNA changes, predicting a valine to methionine change at beta 67, rather than the expected aspartate. Further analysis with electrospray ionization mass spectrometry and globin chain biosynthesis strongly suggests that this anomaly is because of a novel posttranslational mechanism, with slow conversion of the translated methionine into an aspartate residue. The proximity of the heme and oxygen may be important in facilitating the reaction. These findings show the importance of complete characterization of variant hemoglobins using protein, DNA, and biosynthetic analyses.

Why have mortality rates for severe malnutrition remained so high?

A review of the literature that has appeared over the past five decades indicates that the median case fatality from severe malnutrition has remained unchanged over this period and is typically 20-30%, with the highest levels (50-60%) being among those with oedematous malnutrition. A likely cause of this continuing high mortality is faulty case-management. A survey of treatment centres worldwide (n = 79) showed that for acutely ill children, inappropriate diets that are high in protein, energy and sodium and low in micronutrients are commonplace. Practices that could have fatal consequences, such as prescribing diuretics for oedema, were found to be widespread. Evidence of outmoded and conflicting teaching manuals also emerged. Since low mortality levels from malnutrition can be achieved using appropriate treatment regimens, updated treatment guidelines, which are practical and prescriptive rather than descriptive, need to be implemented as part of a comprehensive training programme.

The diets of pregnant and post-pregnant women in different social groups in London and Edinburgh: calcium, iron, retinol, ascorbic acid and folic acid

Dietary records were obtained twice in pregnancy and once post-partum, from 265 women in all social classes in London and Edinburgh. Some Edinburgh women, and lactating women, showed the higher levels of calcium intake. For iron, retinol, ascorbic acid and folic acid, there was a consistent and significant regional and social class gradient in intakes. This favoured English women in 'non-manual' social groups, leaving the Scottish 'manual' class, after pregnancy, with the lowest intakes. Mean intakes of Ca and Fe were consistently below the current UK recommended daily amount (RDA). Intakes of retinol were all above it, and ascorbic acid intakes ranged above and below the RDA.

The diets of pregnant and post-pregnant women in different social groups in London and Edinburgh: energy, protein, fat and fibre

1. Dietary records were obtained twice in pregnancy and once post-partum from 265 women from all social classes in London and Edinburgh. 2. The London women always had higher mean energy, protein, fat and fibre intakes. Significant between-region differences emerged. 3. Some between-social classes differences occurred, but were not consistently significant. 4. All mean energy and fibre intakes were lower, and protein and fat intakes were higher, than current recommendations. 5. Of lactating women 15% claimed to be dieting. 6. The percentage dietary energy derived from fat varied from 36 (in a dieting group) to 42.