Parallel Ada

Much of the focus with multi-core hardware has been on the mapping of tasks to cores. It is important that languages can support both static and dynamic forms of this mapping. However, as the number of cores increase and platforms become more heterogeneous it becomes necessary to identify and support parallel execution within tasks. Various forms of "parallel" statement have been discussed in the literature. Here we argue for the need for simple changes to the language that can go a long way towards exploiting fine grain parallelism.

Targeting the endothelin axis in scleroderma renal crisis: rationale and feasibility

BACKGROUND

We have studied endothelin-1 (ET-1) levels and ET-1 ligand and receptor tissue expression in scleroderma renal crisis (SRC) and undertaken a pilot open label safety study of bosentan, a non-selective ET-1 receptor antagonist, in SRC [Bosentan in Renal Disease-1 (BIRD-1)].

METHODS

Serum levels of ET-1 were measured in healthy controls (n = 20) or systemic sclerosis (SSc) (n = 80) with or without SRC, including cases of pulmonary arterial hypertension (PAH). Renal biopsies (n = 27) from patients with SRC were stained for endothelin ligand and receptors. Six cases of SRC received 6 months bosentan. Outcome measures were compared with SRC cases managed at our centre from 2000 to 2004 (n = 49).

RESULTS

Serum ET-1 was elevated in SRC but less than in PAH. ET-1 and both endothelin A and endothelin B receptor expression was increased in SRC biopsies in glomeruli, interstitium and hallmark vascular lesions of SRC. In the BIRD-1 cohort, serum ET-1 was elevated in all cases at SRC (median healthy controls 0.50 pg/ml; SRC 1.48 pg/ml; P < 0.0005), and increased further with bosentan therapy (1.46 vs. 3.05 pg/ml; t-test P < 0.05). Bosentan was well tolerated with no significant drug-related serious adverse events and long-term outcomes were favourable compared with historic cases. Three patients developed rebound hypertension on withdrawal of bosentan and one appeared to further benefit from maintenance therapy.

CONCLUSION

Upregulation of ET-1 ligand axis suggests that ET-1 receptor blockade is logical and treatment with bosentan appears to be safe in SRC. Future studies to assess therapeutic benefit and compare selective or non-selective receptor antagonists are justified.

Study of the use of antidepressants for depression in dementia: the HTA-SADD trial--a multicentre, randomised, double-blind, placebo-controlled trial of the clinical effectiveness and cost-effectiveness of sertraline and mirtazapine

OBJECTIVE

Depression is common in dementia, causing considerable distress and other negative impacts. Treating it is a clinical priority, but the evidence base is sparse and equivocal. This trial aimed to determine clinical effectiveness of sertraline and mirtazapine in reducing depression 13 weeks post randomisation compared with placebo.

DESIGN

Multicentre, parallel-group, double-blind placebo-controlled randomised controlled trial of the clinical effectiveness of sertraline and mirtazapine with 13- and 39-week follow-up.

SETTING

Nine English old-age psychiatry services.

PARTICIPANTS

A pragmatic trial. Eligibility: probable or possible Alzheimer's disease (AD), depression (4+ weeks) and Cornell Scale for Depression in Dementia (CSDD) score of 8+.

EXCLUSIONS

clinically too critical (e.g. suicide risk); contraindication to medication; taking antidepressants; in another trial; and having no carer.

INTERVENTIONS

(1) Sertraline; (2) mirtazapine; and (3) placebo, all with normal care. Target doses: 150 mg of sertraline or 45 mg of mirtazapine daily.

MAIN OUTCOME MEASURES

OUTCOME

CSDD score. Randomisation: Allocated 1 : 1 : 1 through Trials Unit, independently of trial team. Stratified block randomisation by centre, with randomly varying block sizes; computer-generated randomisation. Blinding: Double blind: medication and placebo identical for each antidepressant. Referring clinicians, research workers, participants and pharmacies were blind. Statisticians blind until analyses completed.

RESULTS

Numbers randomised: 326 participants randomised (111 placebo, 107 sertraline and 108 mirtazapine).

OUTCOME

Differences in CSDD at 13 weeks from an adjusted linear-mixed model: mean difference (95% CI) placebo-sertraline 1.17 (-0.23 to 2.78; p = 0.102); placebo-mirtazapine 0.01 (-1.37 to 1.38; p = 0.991); and mirtazapine-sertraline 1.16 (-0.27 to 2.60; p = 0.112).

HARMS

Placebo group had fewer adverse reactions (29/111, 26%) than sertraline (46/107, 43%) or mirtazapine (44/108, 41%; p = 0.017); 39-week mortality equal, five deaths in each group.

CONCLUSIONS

This is a trial with negative findings but important clinical implications. The data suggest that the antidepressants tested, given with normal care, are not clinically effective (compared with placebo) for clinically significant depression in AD. This implies a need to change current practice of antidepressants being the first-line treatment of depression in AD. From the data generated we formulated the following recommendations for future work. (1) The secondary analyses presented here suggest that there would be value in carrying out a placebo-controlled trial of the clinical effectiveness and cost-effectiveness of mirtazapine in the management of Behavioural and Psychological Symptoms of Dementia. (2) A conclusion from this study is that it remains both ethical and essential for trials of new medication for depression in dementia to have a placebo arm. (3) Further research is required to evaluate the impact that treatments for depression in people with dementia can have on their carers not only in terms of any impacts on their quality of life, but also the time they spend care-giving. (4) There is a need for research into alternative biological and psychological therapies for depression in dementia. These could include evaluations of new classes of antidepressants (such as venlafaxine) or antidementia medication (e.g. cholinesterase inhibitors). (5) Research is needed to investigate the natural history of depression in dementia in the community when patients are not referred to secondary care services. (6) Further work is needed to investigate the cost modelling results in this rich data set, investigating carer burden and possible moderators to the treatment effects. (7) There is scope for reanalysis of the primary outcome in terms of carer and participant CSDD results.

Health and social care services for older male adults in prison: the identification of current service provision and piloting of an assessment and care planning model

Background

Older prisoners are the fastest growing subgroup in the English and Welsh prison estate. Existing research highlights that older prisoners have high health and social care needs and that, currently, these needs routinely remain unmet.

Objectives

(1) To explore the needs of men entering and leaving prison; (2) to describe current provision of services, including integration between health and social care services; and (3) to develop and pilot an intervention for identifying health and social care needs on reception into prison, ensuring that these are systematically addressed during custody.

Methods

The research programme was a mixed-methods study comprising four parts: (1) a study of all prisons in England and Wales housing older adult men, establishing current availability and degree of integration between health and social care services through a national survey and qualitative interviews; (2) establishing the health and social care needs of older men entering prison, including experiences of reception into custody, through structured (n = 100) and semistructured (n = 27) interviews; (3) the development and implementation of an intervention to identify and manage the health, social care and custodial needs of older men entering prison; and (4) exploration of the health and social care needs of older men released from prison into the community through qualitative interviews with older prisoners prior to and following discharge from prison. Descriptive statistics were produced for all quantitative data, and qualitative data were analysed using the constant comparison method.

Results

The number of older prisoner leads has increased in recent years but they do not all appear always to be active in their roles, nor in receipt of specialist training. Nearly half (44%) of establishments do not have an older prisoner policy. There is a lack of integration between health and social care services because of ambiguity regarding responsibility for older prisoners' social care. The responsible social service may be located a considerable distance from where the prisoner is held; in such instances, local social services do not co-ordinate their care. The most frequent unmet need on prison entry was the provision of information about care and treatment. Release planning for older prisoners was frequently non-existent.

Limitations

The study used a cut-off age of 60 years as the lower limit for the definition of an older prisoner; evidence has emerged that supports a redefinition of that cut-off to 50 years. Our study examined the care provided for men and this should be considered if contemplating using the Older prisoner Health and Social Care Assessment and Plan (OHSCAP) with older women in prison.

Conclusion

The OHSCAP, developed as part of this study, provided a feasible and acceptable means of identifying and systematically addressing older prisoners' health and social care needs. Future work will include the conduct of a randomised controlled trial to examine the impact of the OHSCAP in terms of improving a range of outcomes, including economic impact.

Funding

The National Institute for Health Research Health Services and Delivery Research programme.

Mutations in SETBP1 are recurrent in myelodysplastic syndromes and often coexist with cytogenetic markers associated with disease progression

Whole exome sequencing was performed in a patient with myelodysplastic syndrome before and after progression to acute myeloid leukaemia. Mutations in several genes, including SETBP1, were identified following leukaemic transformation. Screening of 328 patients with myeloid disorders revealed SETBP1 mutations in 14 patients (4·3%), 7 of whom had -7/del(7q) and 3 had i(17)(q10), cytogenetic markers associated with shortened overall survival and increased risk of leukaemic evolution. SETBP1 mutations were frequently acquired at the time of leukaemic evolution, coinciding with increase of leukaemic blasts. These data suggest that SETBP1 mutations may play a role in MDS and chronic myelomonocytic leukaemia disease progression.

Paradoxical embolization: a potential cause of cerebral damage in Alzheimer's disease?

BACKGROUND

There are considerable overlaps between vascular dementia and Alzheimer's disease (AD), with a suggestion that cerebrovascular disease (CVD) contributes to the neurodegenerative pathology of AD. Paradoxical embolization of venous emboli into the systemic circulation through a venous to arterial circulation shunt (v-aCS), the most commonly a patent foramen ovale (PFO), is known to cause cryptogenic stroke in younger people. We reviewed the potential role of paradoxical embolization in AD.

METHODS

A review of the literature on paradoxical embolization in neurological disorders and techniques to detect v-aCS and PFO, supplemented by data from our own studies.

RESULTS

Before our research, the role of paradoxical embolism in dementia had not been studied. The potential role of embolization in cerebral damage was highlighted by studies in patients undergoing coronary artery bypass or carotid surgery. Paradoxical embolization was found to occur in patients with cryptogenic stroke, migraine, decompression sickles and during hip surgery. The methods for detecting v-aCS or PFO had not been standardized. We found 'significant' v-aCS (equivalent to PFO) in 32% of AD patients compared with 22% of controls, but the study was not sufficiently powered to test the statistic significance of this difference. In AD, there was evidence of an association between 'significant' v-aCS and the severity of white matter hyperintensities on magnetic resonance imaging (MRI).

CONCLUSION

Paradoxical embolization through a v-aCS may be a potentially preventable or treatable cause of CVD in AD.

Targeted re-sequencing analysis of 25 genes commonly mutated in myeloid disorders in del(5q) myelodysplastic syndromes

Interstitial deletion of chromosome 5q is the most common chromosomal abnormality in myelodysplastic syndromes. The catalogue of genes involved in the molecular pathogenesis of myelodysplastic syndromes is rapidly expanding and next-generation sequencing technology allows detection of these mutations at great depth. Here we describe the design, validation and application of a targeted next-generation sequencing approach to simultaneously screen 25 genes mutated in myeloid malignancies. We used this method alongside single nucleotide polymorphism-array technology to characterize the mutational and cytogenetic profile of 43 cases of early or advanced del(5q) myelodysplastic syndromes. A total of 29 mutations were detected in our cohort. Overall, 45% of early and 66.7% of advanced cases had at least one mutation. Genes with the highest mutation frequency among advanced cases were TP53 and ASXL1 (25% of patients each). These showed a lower mutation frequency in cases of 5q- syndrome (4.5% and 13.6%, respectively), suggesting a role in disease progression in del(5q) myelodysplastic syndromes. Fifty-two percent of mutations identified were in genes involved in epigenetic regulation (ASXL1, TET2, DNMT3A and JAK2). Six mutations had allele frequencies <20%, likely below the detection limit of traditional sequencing methods. Genomic array data showed that cases of advanced del(5q) myelodysplastic syndrome had a complex background of cytogenetic aberrations, often encompassing genes involved in myeloid disorders. Our study is the first to investigate the molecular pathogenesis of early and advanced del(5q) myelodysplastic syndromes using next-generation sequencing technology on a large panel of genes frequently mutated in myeloid malignancies, further illuminating the molecular landscape of del(5q) myelodysplastic syndromes.

An analysis of workplace exposures to benzene over four decades at a petrochemical processing and manufacturing facility (1962-1999)

Benzene, a known carcinogen, can be generated as a by-product during the use of petroleum-based raw materials in chemical manufacturing. The aim of this study was to analyze a large data set of benzene air concentration measurements collected over nearly 40 years during routine employee exposure monitoring at a petrochemical manufacturing facility. The facility used ethane, propane, and natural gas as raw materials in the production of common commercial materials such as polyethylene, polypropylene, waxes, adhesives, alcohols, and aldehydes. In total, 3607 benzene air samples were collected at the facility from 1962 to 1999. Of these, in total 2359 long-term (>1 h) personal exposure samples for benzene were collected during routine operations at the facility between 1974 and 1999. These samples were analyzed by division, department, and job title to establish employee benzene exposures in different areas of the facility over time. Sampling data were also analyzed by key events over time, including changes in the occupational exposure limits (OELs) for benzene and key equipment process changes at the facility. Although mean benzene concentrations varied according to operation, in nearly all cases measured benzene quantities were below the OEL in place at the time for benzene (10 ppm for 1974-1986 and 1 ppm for 1987-1999). Decreases in mean benzene air concentrations were also found when data were evaluated according to 7- to 10-yr periods following key equipment process changes. Further, an evaluation of mortality rates for a retrospective employee cohort (n = 3938) demonstrated that the average personal benzene exposures at this facility (0.89 ppm for the period 1974-1986 and 0.125 ppm for the period 1987-1999) did not result in increased standardized mortality ratio (SMRs) for diseases or malignancies of the lymphatic system. The robust nature of this data set provides comprehensive exposure information that may be useful for assessing human benzene exposures at similar facilities. The data also provide a basis for comparable measured exposure levels and the potential for adverse health effects. These data may also prove beneficial for comparing relative exposure potential for production versus nonproduction operations and the relationship between area and personal breathing zone samples.

Investigation of the persistence and transmission of MRSA CC 5 in pigs following intra-nasal inoculation

MRSA CC5 spa type t002 appears to have a broad host range, has been isolated from animals and in-contact humans in Ireland and could potentially become established in pigs in Ireland. The aims of this study were to determine if MRSA CC5 spa type t002 could persist in the tissues of the porcine upper respiratory tract following intra-nasal inoculation; to determine the relative importance of environmental and animal sources of the bacterium in the transmission cycle and to determine the importance of the pharynx as a carriage site of Staphylococcus aureus and MRSA. Twelve pigs were inoculated intra-nasally with MRSA CC5 t002. After 1 or 6 days, the inoculated pigs were removed from the contaminated environment, were washed in an antiseptic solution and placed in a clean house with a group of naive pigs (in-contact group). Another group of naive pigs was placed in the contaminated environment to assess transmission from the environment (environmental group). Nasal swabs, environmental swabs and tissue samples from the upper respiratory tract were taken for MRSA culture. Infection rates were calculated for each group of exposed pigs. MRSA persisted in the pharyngeal tissues of 6 inoculated pigs for at least 30 days and higher counts of S. aureus were found in pharyngeal tissues than in other sites. In this study we were able to demonstrate the establishment of colonisation by MRSA CC5 spa type t002 in commercially sourced pigs already colonised by S. aureus; however, colonisation was sporadic despite the inoculation of large doses. Onward transmission via pig-to-pig contact or environmental contamination was possible and a significant difference was found between the proportion of pigs infected in the environmental group and the proportion infected in the in-contact group during the first 5 days. However, no significant difference was detected in overall infection rates between the 2 groups. The tissues of the pharynx were found to carry greater numbers of S. aureus than other tissues of the upper respiratory tract; therefore, pharyngeal carriage of MRSA and S. aureus in pigs may be more significant than previously thought.