A rapid intrapartum test for group B Streptococcus to reduce antibiotic usage in mothers with risk factors: the GBS2 cluster RCT

BACKGROUND

Mother-to-baby transmission of group B Streptococcus (Streptococcus agalactiae) is the main cause of early-onset infection.

OBJECTIVES

We investigated if intrapartum antibiotic prophylaxis directed by a rapid intrapartum test reduces maternal and neonatal antibiotic use, compared with usual care (i.e. risk factor-directed antibiotics), among women with risk factors for vertical group B Streptococcus transmission, and examined the accuracy and cost-effectiveness of the rapid test.

DESIGN

An unblinded cluster randomised controlled trial with a nested test accuracy study, an economic evaluation and a microbiology substudy.

SETTING

UK maternity units were randomised to either a strategy of rapid test or usual care.

PARTICIPANTS

Vaginal and rectal swabs were taken from women with risk factors for vertical group B Streptococcus transmission in established term labour. The accuracy of the GeneXpert^® Dx IV GBS rapid testing system (Cepheid, Maurens-Scopont, France) was compared with the standard of selective enrichment culture in diagnosing maternal group B Streptococcus colonisation.

MAIN OUTCOME MEASURES

Primary outcomes were rates of intrapartum antibiotic prophylaxis administered to prevent early-onset group B Streptococcus infection and accuracy estimates of the rapid test. Secondary outcomes were maternal antibiotics for any indication, neonatal antibiotic exposure, maternal antibiotic duration, neonatal group B Streptococcus colonisation, maternal and neonatal antibiotic resistance, neonatal morbidity and mortality, and cost-effectiveness of the strategies.

RESULTS

Twenty-two maternity units were randomised and 20 were recruited. A total of 722 mothers (749 babies) participated in rapid test units and 906 mothers (951 babies) participated in usual-care units. There were no differences in the rates of intrapartum antibiotic prophylaxis for preventing early-onset group B Streptococcus infection in the rapid test units (41%, 297/716) compared with the usual-care units (36%, 328/906) (risk ratio 1.16, 95% confidence interval 0.83 to 1.64). There were no differences between the groups in intrapartum antibiotic administration for any indication (risk ratio 0.99, 95% confidence interval 0.81 to 1.21). Babies born in the rapid test units were 29% less likely to receive antibiotics (risk ratio 0.71, 95% confidence interval 0.54 to 0.95) than those born in usual-care units. The sensitivity and specificity of the rapid test were 86% (95% confidence interval 81% to 91%) and 89% (95% confidence interval 85% to 92%), respectively. In 14% of women (99/710), the rapid test was invalid or the machine failed to provide a result. In the economic analysis, the rapid test was shown to be both less effective and more costly and, therefore, dominated by usual care. Sensitivity analysis indicated potential lower costs for the rapid test strategy when neonatal costs were included. No serious adverse events were reported.

CONCLUSIONS

The Group B Streptococcus 2 (GBS2) trial found no evidence that the rapid test reduces the rates of intrapartum antibiotic prophylaxis administered to prevent early-onset group B Streptococcus infection. The rapid test has the potential to reduce neonatal exposure to antibiotics, but economically is dominated by usual care. The accuracy of the test is within acceptable limits.

FUTURE WORK

The role of routine testing for prevention of neonatal infection requires evaluation in a randomised controlled trial.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN74746075.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 12. See the NIHR Journals Library website for further project information.

Immediate birth for women between 34 and 37 weeks of gestation with prolonged preterm prelabour rupture of membranes and detection of vaginal or urine group B streptococcus: an economic evaluation

Objective

What are the costs, benefits and harms of immediate birth compared with expectant management in women with prolonged preterm prelabour rupture of membranes (PPROM) at 34⁺⁰–36⁺⁶ weeks of gestation and detection of vaginal or urine group B streptococcus (GBS)?

Design

Mathematical decision model comprising three independent decision trees.

Setting

UK National Health Service (NHS) and personal social services perspective.

Population

Women testing positive for GBS with PPROM at 34⁺⁰–36⁺⁶ weeks of gestation.

Methods

The model estimates lifetime costs and quality‐adjusted life years (QALYs) using evidence from randomised trials, UK NHS data sources and further observational studies. Simulated events include neonatal infections, morbidity associated with preterm birth and consequences of caesarean birth. Deterministic and probabilistic sensitivity analyses (PSAs) were performed.

Main outcome measures

QALYs, costs and incremental cost‐effectiveness ratio (ICER).

Results

In this population, immediate birth dominates expectant management: it is more effective (average lifetime QALYs, 24.705 versus 24.371) and it is cheaper (average lifetime costs, £14,372 versus £19,311). In one‐way sensitivity analysis, results are robust to all but the odds ratio estimating the relative effect on incidence of infections. Threshold analysis shows that the odds of infection only need to be >1.5% with expectant management for the benefit of avoiding infections to outweigh the disadvantages of immediate birth. In PSA, immediate birth is the preferred option in >80% of simulations.

Conclusions

Neonatal GBS infections are expensive to treat and may result in substantial adverse health consequences. Therefore, immediate birth, which is associated with a reduced risk of neonatal infection compared with expectant management, is expected to generate better health outcomes and decreased lifetime costs.

Tweetable abstract

For women with preterm prelabour rupture of membranes and group B streptococcus in vaginal or urine samples, immediate birth is associated with improved health in their babies and reduced costs, compared with expectant management.

For women with preterm prelabour rupture of membranes and group B streptococcus in vaginal or urine samples, immediate birth is associated with improved health in their babies and reduced costs, compared with expectant management.

Rapid intrapartum test for maternal group B streptococcal colonisation and its effect on antibiotic use in labouring women with risk factors for early-onset neonatal infection (GBS2): cluster randomised trial with nested test accuracy study

BACKGROUND

Mother-to-baby transmission of group B Streptococcus (GBS) is the main cause of early-onset infection. We evaluated whether, in women with clinical risk factors for early neonatal infection, the use of point-of-care rapid intrapartum test to detect maternal GBS colonisation reduces maternal antibiotic exposure compared with usual care, where antibiotics are administered due to those risk factors. We assessed the accuracy of the rapid test in diagnosing maternal GBS colonisation, against the reference standard of selective enrichment culture.

METHODS

We undertook a parallel-group cluster randomised trial, with nested test accuracy study and microbiological sub-study. UK maternity units were randomised to a strategy of rapid test (GeneXpert GBS system, Cepheid) or usual care. Within units assigned to rapid testing, vaginal-rectal swabs were taken from women with risk factors for vertical GBS transmission in established term labour. The trial primary outcome was the proportion of women receiving intrapartum antibiotics to prevent neonatal early-onset GBS infection. The accuracy of the rapid test was compared against the standard of selective enrichment culture in diagnosing maternal GBS colonisation. Antibiotic resistance profiles were determined in paired maternal and infant samples.

RESULTS

Twenty-two maternity units were randomised and 20 were recruited. A total of 722 mothers (749 babies) participated in rapid test units; 906 mothers (951 babies) were in usual care units. There was no evidence of a difference in the rates of intrapartum antibiotic prophylaxis (relative risk 1.16, 95% CI 0.83 to 1.64) between the rapid test (41%, 297/716) and usual care (36%, 328/906) units. No serious adverse events were reported. The sensitivity and specificity measures of the rapid test were 86% (95% CI 81 to 91%) and 89% (95% CI 85 to 92%), respectively. Babies born to mothers who carried antibiotic-resistant Escherichia coli were more likely to be colonised with antibiotic-resistant strains than those born to mothers with antibiotic-susceptible E. coli.

CONCLUSION

The use of intrapartum rapid test to diagnose maternal GBS colonisation did not reduce the rates of antibiotics administered for preventing neonatal early-onset GBS infection than usual care, although with considerable uncertainty. The accuracy of the rapid test is within acceptable limits.

TRIAL REGISTRATION

ISRCTN74746075 . Prospectively registered on 16 April 2015.

Group B streptococcal disease in the mother and newborn-A review

Group B Streptococcus, a common commensal in the gut of humans and in the lower genital tract in women, remains an important cause of neonatal mortality and morbidity. The incidence of early onset disease has fallen markedly in countries that test women for carriage at 35-37 weeks of pregnancy and then offer intrapartum prophylaxis with penicillin during labour. Countries that do not test, but instead employ a risk factor approach, have not seen a similar fall. There are concerns about the effect on the neonatal microbiome of widespread use of antibiotic prophylaxis during labour, but so far the effects seem minor and temporary. Vaccination against GBS would be acceptable to most women and GBS vaccines are in the early stages of development. Tweetable abstract: Group B Strep is a key cause of infection, death and disability in young babies. Antibiotics given in labour remain the mainstay of prevention, until a vaccine is available.

Uncertainties in Screening and Prevention of Group B Streptococcus Disease

In autumn 2016, the UK Department of Health (now Department of Health and Social Care) convened 2 meetings to discuss how to address research evidence gaps in order to minimize the impact of infant group B streptococcus (GBS) disease in the United Kingdom. At that meeting, a number of research priorities were highlighted, including improving the screening for GBS colonization in pregnant women, offering intrapartum antibiotic prophylaxis and point-of-care testing, and understanding the effect of widespread intrapartum antibiotic use on long-term infant health. Further discussions involved investigating the feasibility of a large prospective study of pregnant women and their infants in order to understand the role of antibodies in the protection against GBS disease in infancy following maternal exposure to GBS colonization. Here, we summarize the research uncertainties identified at that meeting.

Developing a serocorrelate of protection against invasive group B streptococcus disease in pregnant women: a feasibility study

BACKGROUND

Group B streptococcus is the leading cause of infection in infants. Currently, intrapartum antibiotic prophylaxis is the major strategy to prevent invasive group B streptococcus disease. However, intrapartum antibiotic prophylaxis does not prevent maternal sepsis, premature births, stillbirths or late-onset disease. Maternal vaccination may offer an alternative strategy. Multivalent polysaccharide protein conjugate vaccine development is under way and a serocorrelate of protection is needed to expedite vaccine licensure.

OBJECTIVES

The ultimate aim of this work is to determine the correlate of protection against the major group B streptococcus disease-causing serotypes in infants in the UK. The aim of this feasibility study is to test key operational aspects of the study design.

DESIGN

Prospective cohort study of pregnant women and their infants in a 6-month period (1 July to 31 December 2018).

SETTING

Five secondary and tertiary hospitals from London and South England. National iGBS disease surveillance was conducted in all trusts in England and Wales.

PARTICIPANTS

Pregnant women aged ≥ 18 years who were delivering at one of the selected hospitals and who provided consent during the study period. There were no exclusion criteria.

INTERVENTIONS

No interventions were performed.

MAIN OUTCOME MEASURES

(1) To test the feasibility of collecting serum at delivery from a large cohort of pregnant women. (2) To test the key operational aspects for a proposed large serocorrelates study. (3) To test the feasibility of collecting samples from those with invasive group B streptococcus.

RESULTS

A total of 1823 women were recruited during the study period. Overall, 85% of serum samples were collected at three sites collecting only cord blood. At the two sites collecting maternal, cord and infant blood samples, the collection rate was 60%. A total of 614 women were screened for group B streptococcus with a colonisation rate of 22% (serotype distribution: 30% III, 25% Ia, 16% II, 14% Ib, 14% V and 1% IV). A blood sample was collected from 34 infants who were born to colonised women. Maternal and infant blood and the bacterial isolates for 15 newborns who developed invasive group B streptococcal disease during the study period were collected (serotype distribution: 29% III, 29% II, 21% Ia, 7% Ib, 7% IV and 7% V).

LIMITATIONS

Recruitment and sample collection were dependent on the presence of research midwives rather than the whole clinical team. In addition, individualised consent limited the number of women who could be approached each day, and site set-up for the national surveillance study and the limited time period of this feasibility study limited recruitment of all eligible participants.

CONCLUSIONS

We have verified the feasibility of collecting and processing rectovaginal swabs and blood samples in pregnant women, as well as samples from those with invasive group B streptococcal disease. We have made recommendations for the recruitment of cases within the proposed GBS3 study and for controls both within GBS3 and as an extension of this feasibility study.

FUTURE WORK

A large case-control study comparing specific immunoglobulin G levels in mothers whose infants develop invasive group B streptococcal disease with those in colonised mothers whose infants do not develop invasive group B streptococcal disease is recommended.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN49326091; IRAS project identification number 246149/REC reference number 18/WM/0147.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 67. See the NIHR Journals Library website for further project information.

Cardiopulmonary exercise testing (CPET) in the United Kingdom-a national survey of the structure, conduct, interpretation and funding

Background

Cardiopulmonary exercise testing (CPET) is an exercise stress test with concomitant expired gas analysis that provides an objective, non-invasive measure of functional capacity under stress. CPET-derived variables predict postoperative morbidity and mortality after major abdominal and thoracic surgery. Two previous surveys have reported increasing utilisation of CPET preoperatively in England. We aimed to evaluate current CPET practice in the UK, to identify who performs CPET, how it is performed, how the data generated are used and the funding models.

Methods

All anaesthetic departments in trusts with adult elective surgery in the UK were contacted by telephone to obtain contacts for their pre-assessment and CPET service leads. An online survey was sent to all leads between November 2016 and March 2017.

Results

The response rate to the online survey was 73.1% (144/197) with 68.1% (98/144) reporting an established clinical service and 3.5% (5/144) setting up a service. Approximately 30,000 tests are performed a year with 93.0% (80/86) using cycle ergometry. Colorectal surgical patients are the most frequently tested (89.5%, 77/86). The majority of tests are performed and interpreted by anaesthetists. There is variability in the methods of interpretation and reporting of CPET and limited external validation of results.

Conclusions

This survey has identified the continued expansion of perioperative CPET services in the UK which have doubled since 2011. The vast majority of CPET tests are performed and reported by anaesthetists. It has highlighted variation in practice and a lack of standardised reporting implying a need for practice guidelines and standardised training to ensure high-quality data to inform perioperative decision making.

Hypoxia-inducible factor 1 alpha is required for the tumourigenic and aggressive phenotype associated with Rab25 expression in ovarian cancer

The small GTPase Rab25 has been functionally linked to tumour progression and aggressiveness in ovarian cancer and promotes invasion in three-dimensional environments. This type of migration has been shown to require the expression of the hypoxia-inducible factor 1 alpha (HIF-1α). In this report we demonstrate that Rab25 regulates HIF-1α protein expression in an oxygen independent manner in a panel of cancer cell lines. Regulation of HIF-1α protein expression by Rab25 did not require transcriptional upregulation, but was dependent on de novo protein synthesis through the Erbb2/ERK1/2 and p70S6K/mTOR pathways. Rab25 expression induced HIF-1 transcriptional activity, increased cisplatin resistance, and conferred intraperitoneal growth to the A2780 cell line in immunocompromised mice. Targeting HIF1 activity by silencing HIF-1β re-sensitised cells to cisplatin in vitro and reduced tumour formation of A2780-Rab25 expressing cells in vivo in a mouse ovarian peritoneal carcinomatosis model. Similar effects on cisplatin resistance in vitro and intraperitoneal tumourigenesis in vivo were obtained after HIF1b knockdown in the ovarian cancer cell line SKOV3, which expresses endogenous Rab25 and HIF-1α at atmospheric oxygen concentrations. Our results suggest that Rab25 tumourigenic potential and chemoresistance relies on HIF1 activity in aggressive and metastatic ovarian cancer. Targeting HIF-1 activity may potentially be effective either alone or in combination with standard chemotherapy for aggressive metastatic ovarian cancer.

Expression of ADAMTS-1, -4, -5 and TIMP-3 in normal and multiple sclerosis CNS white matter

ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) -1, -4 and -5 proteases have been identified in the CNS at the mRNA level. These glutamyl endopeptidases, inhibited by tissue inhibitor of metalloproteinases (TIMP)-3, are key enzymes in the degradation of the aggregating chondroitin sulphate proteoglycans (CSPGs), and may therefore play a role in CNS extracellular matrix (ECM) changes in multiple sclerosis (MS). We have investigated ADAMTS and TIMP-3 expression in normal and MS CNS white matter by real-time RT-PCR, western blotting and immunohistochemistry. We report for the first time the presence of ADAMTS-1, -4 and -5 in normal and MS white matter. Levels of ADAMTS-1 and -5 mRNA were decreased in MS compared to normal tissue, with no significant change in ADAMTS-4 mRNA levels. Protein levels of ADAMTS-4 were significantly higher in MS tissue compared to normal tissue. Immunohistochemical studies demonstrated that ADAMTS-4 was associated predominantly with astrocytes with increased expression within MS lesions. TIMP-3 mRNA was significantly decreased in MS compared to controls. These studies suggest a role for ADAMTS-4 in the pathogenesis of MS. Further studies on the activity of ADAMTS-4 will enable a better understanding of its role in the turnover of the ECM of white matter in MS.

Attitudes towards antenatal vaccination, Group B streptococcus and participation in clinical trials: Insights from focus groups and interviews of parents and healthcare professionals

INTRODUCTION

Antenatal vaccination has become a part of routine care during pregnancy in the UK and worldwide, leading to improvements in health for both pregnant women and their infants. However, uptake remains sub-optimal. Other antenatal vaccines targeting major neonatal pathogens, such as Group B streptococcus (GBS), the commonest cause of sepsis and meningitis in the neonatal period, are undergoing clinical trials but more information is needed on how to improve acceptance of such vaccines.

METHODS

Qualitative study using focus groups and interviews; involving 14 pregnant women, 8 mothers with experience of GBS, and 28 maternity healthcare professionals. Questions were asked regarding antenatal vaccines, knowledge of GBS, attitudes to a potential future GBS vaccine and participation in antenatal vaccine trials.

RESULTS

All participants were very cautious about vaccination during pregnancy, with harm to the baby being a major concern. Despite this, the pregnant women and parents with experience of GBS were open to the idea of an antenatal GBS vaccine and participating in research, while the maternity professionals were less positive. Major barriers identified included lack of knowledge about GBS and the reluctance of maternity professionals to be involved.

INTERPRETATION

In order for a future GBS vaccine to be acceptable to both pregnant women and the healthcare professionals advising them, a major awareness campaign would be required with significant focus on convincing and training maternity professionals.

Factors influencing women's attitudes towards antenatal vaccines, group B Streptococcus and clinical trial participation in pregnancy: an online survey

OBJECTIVES

To explore factors influencing the likelihood of antenatal vaccine acceptance of both routine UK antenatal vaccines (influenza and pertussis) and a hypothetical group B Streptococcus (GBS) vaccine in order to improve understanding of how to optimise antenatal immunisation acceptance, both in routine use and clinical trials.

SETTING

An online survey distributed to women of childbearing age in the UK.

PARTICIPANTS

1013 women aged 18-44 years in England, Scotland and Wales.

METHODS

Data from an online survey conducted to gauge the attitudes of 1013 women of childbearing age in England, Scotland and Wales to antenatal vaccination against GBS were further analysed to determine the influence of socioeconomic status, parity and age on attitudes to GBS immunisation, using attitudes to influenza and pertussis vaccines as reference immunisations. Factors influencing likelihood of participation in a hypothetical GBS vaccine trial were also assessed.

RESULTS

Women with children were more likely to know about each of the 3 conditions surveyed (GBS: 45% vs 26%, pertussis: 79% vs 63%, influenza: 66% vs 54%), to accept vaccination (GBS: 77% vs 65%, pertussis: 79% vs 70%, influenza: 78% vs 68%) and to consider taking part in vaccine trials (37% vs 27% for a hypothetical GBS vaccine tested in 500 pregnant women). For GBS, giving information about the condition significantly increased the number of respondents who reported that they would be likely to receive the vaccine. Health professionals were the most important reported source of information.

CONCLUSIONS

Increasing awareness about GBS, along with other key strategies, would be required to optimise the uptake of a routine vaccine, with a specific focus on informing women without previous children. More research specifically focusing on acceptability in pregnant women is required and, given the value attached to input from healthcare professionals, this group should be included in future studies.

Clinical characteristics and airway inflammation profile of COPD persistent sputum producers

BACKGROUND

COPD patients with chronic bronchitis include a subgroup with persistent sputum production on most or every day. We hypothesized that COPD patients with persistent sputum production have a different profile of airway inflammation, and more severe clinical characteristics.

OBJECTIVE

To compare the airway inflammation profile and clinical characteristics of COPD persistent and non-persistent sputum producers.

METHODS

COPD persistent sputum producers (n = 26) and non-persistent sputum producers (n = 26) underwent sputum induction and pulmonary function tests. Exacerbation history was recorded; the St. George's Respiratory Questionnaire, Modified Medical Research Council Dyspnoea scale and COPD Assessment Tool were completed. 33 COPD patients provided sputum for bacteriology.

RESULTS

Persistent sputum producers had lower post-bronchodilator FEV1% predicted (p = 0.01), diffusion capacity (p = 0.04), 6 min walk test distance (p = 0.05), and higher closing volume (p = 0.01), BODE index (p = 0.01), rate of bacterial colonization (p = 0.004) and exacerbations (p = 0.03) compared to non-persistent sputum producers. The mean SGRQ and CAT scores were higher in persistent sputum producers (p = 0.01 and 0.03 respectively). Sputum neutrophil and eosinophil total cell counts were higher in persistent sputum producers (p = 0.02 and 0.05 respectively). Sputum levels of eotaxin (p = 0.02), MCP-1 (p = 0.02), TNF-α (p = 0.03) and IL-6 (p = 0.05) were higher in persistent sputum producers.

CONCLUSION

COPD persistent sputum producers have more severe clinical characteristics and increased concentrations of some inflammatory mediators in the airways.

Group B streptococcus infection: risk and prevention

Group B Streptococcus (group B Strep or GBS) is the UK's commonest cause of severe early-onset (up to six days) infection in babies. GBS is a normal body commensal, colonising the gut and vagina. GBS may pass to babies around childbirth; although most are unaffected, some develop severe infection. GBS is also a recognised cause of stillbirth and puerperal sepsis. Most GBS infection in babies is of early onset and most of these infections are highly preventable with the targeted use of intrapartum antibiotic prophylaxis. This article reviews current UK guidelines and prevention strategies.

IFN-γ synergistically enhances LPS signalling in alveolar macrophages from COPD patients and controls by corticosteroid-resistant STAT1 activation

BACKGROUND AND PURPOSE

IFN-γ levels are increased in chronic obstructive airway disease (COPD) patients compared with healthy subjects and are further elevated during viral exacerbations. IFN-γ can 'prime' macrophages to enhance the response to toll-like receptor (TLR) ligands, such as LPS. The aim of this study was to examine the effect IFN-γ on corticosteroid sensitivity in alveolar macrophages (AM).

EXPERIMENTAL APPROACH

AM from non-smokers, smokers and COPD patients were stimulated with IFN-γ and/or LPS with or without dexamethasone. IL-6, TNF-α and IFN-γ-induced protein 10 kDa (IP-10) levels were measured by elisa, and Western blots were used to investigate the IFN-γ-stimulated Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signalling pathway. Real-time PCR and flow cytometry were used to investigate TLR levels following IFN-γ treatment.

KEY RESULTS

In all three subject groups, IFN-γ alone had no effect on IL-6 and TNF-α production but enhanced the effects of LPS on these cytokines. In contrast, IFN-γ alone increased the production of IP-10. IFN-γ increased TLR2 and TLR4 expression in AM. Cytokine induction and STAT1 activation by IFN-γ were insensitive to dexamethasone for all groups. The inhibition of JAK and STAT1 repressed all these IFN-γ effects.

CONCLUSIONS AND IMPLICATIONS

Our results demonstrate that IFN-γ-induced STAT-1 signalling is corticosteroid resistant in AMs, and that targeting IFN-γ signalling by JAK inhibitors is a potentially novel anti-inflammatory strategy in COPD.

Myth: Group B streptococcal infection in pregnancy: comprehended and conquered

Group B streptococcus (GBS) is a common inhabitant of the bowel, and frequently colonises the vagina. It rarely causes disease, except in neonates, where it is the most common cause of serious neonatal infection. Although GBS can be transmitted sexually, it is common even in adults who have never been sexually active and is not a sexually transmitted disease. Currently, the most widely used effective method for detecting colonisation is taking a low vaginal and rectal swab and culturing GBS using enriched media culture. GBS cannot reliably be eradicated by antibiotic treatment but intravenous penicillin given to the mother during labour can prevent up to 90% of early onset GBS disease. Screening and antibiotic prophylaxis has resulted in an 80% fall in early onset disease in the USA, and has been successfully implemented in many countries. There is no systematic screening in the UK, where the incidence continues to rise.

Interferon-inducible factor 16 is a novel modulator of glucocorticoid action

Previously, we used cDNA expression profiling to identify genes associated with glucocorticoid (Gc) sensitivity. We now identify which of these directly influence Gc action. Interferon-inducible protein 16 (IFI16), bone morphogenetic protein receptor type II (BMPRII), and regulator of G-protein signaling 14 (RGS14) increased Gc transactivation, whereas sialyltransferase 4B (SIAT4B) had a negative effect. Amyloid β (A4) precursor-protein binding, family B, member 1 (APBB1/Fe65) and neural cell expressed developmentally down-regulated 9 (NEDD9) were without effect. Only IFI16 potentiated Gc repression of NF-κB. In addition, IFI16 affected basal expression, and Gc induction of endogenous target genes. IFI16 did not affect glucocorticoid receptor (GR) expression, ligand-dependent repression of GR expression, or the ligand-dependent induction of GR phosphorylation on Ser-211 or Ser-203. Coimmunoprecipitation revealed an interaction, suggesting that IFI16 modulation of GR function is mediated by protein crosstalk. Transfection analysis with GR mutants showed that the ligand-binding domain of GR binds IFI16 and is the target domain for IFI16 regulation. Analysis of human lung sections identified colocalization of GR and IFI16, suggesting a physiologically relevant interaction. We demonstrate that IFI16 is a novel modulator of GR function and show the importance of analyzing variation in Gc sensitivity in humans, using appropriate technology, to drive discovery.—Berry, A., Matthews, L. Jangani, M., Plumb, J., Farrow, S., Buchan, N., Wilson, P. A., Singh, D., Ray, D., W., Donn, R. P. Interferon-inducible factor 16 is a novel modulator of glucocorticoid action.

Increased T-regulatory cells within lymphocyte follicles in moderate COPD

Lymphoid follicles in the lung parenchyma are a characteristic feature of chronic obstructive pulmonary disease (COPD). There are reports of altered CD4 T-regulatory cell numbers in COPD lungs, but the location of these cells within COPD lung tissue specific follicles has not been investigated. The presence of CD4(+)FOXP3(+) T-regulatory cells was assessed in surgically resected lung tissue from 12 COPD patients, 11 smokers with normal lung function and seven nonsmokers by combined immunofluorescence and immunohistochemistry. Organised lymphoid follicles were observed in all three groups of patients, as well as lymphoid clusters lacking organisation. The percentage of CD4 cells that were T-regulatory cells were significantly increased (p = 0.02) within COPD (16%) follicles compared with smokers (10%) and nonsmokers (8%). In contrast, there was no change (p>0.05) in the percentage of T-regulatory cells in clusters or the subepithelium between groups. Lymphoid follicles in COPD patients have increased T-regulatory cells. Therefore, T-regulatory activity may be altered within COPD lymphoid follicles.

Circadian timing in the lung; a specific role for bronchiolar epithelial cells

In addition to the core circadian oscillator, located within the suprachiasmatic nucleus, numerous peripheral tissues possess self-sustaining circadian timers. In vivo these are entrained and temporally synchronized by signals conveyed from the core oscillator. In the present study, we examine circadian timing in the lung, determine the cellular localization of core clock proteins in both mouse and human lung tissue, and establish the effects of glucocorticoids (widely used in the treatment of asthma) on the pulmonary clock. Using organotypic lung slices prepared from transgenic mPER2::Luc mice, luciferase levels, which report PER2 expression, were measured over a number of days. We demonstrate a robust circadian rhythm in the mouse lung that is responsive to glucocorticoids. Immunohistochemical techniques were used to localize specific expression of core clock proteins, and the glucocorticoid receptor, to the epithelial cells lining the bronchioles in both mouse and human lung. In the mouse, these were established to be Clara cells. Murine Clara cells retained circadian rhythmicity when grown as a pure population in culture. Furthermore, selective ablation of Clara cells resulted in the loss of circadian rhythm in lung slices, demonstrating the importance of this cell type in maintaining overall pulmonary circadian rhythmicity. In summary, we demonstrate that Clara cells are critical for maintaining coherent circadian oscillations in lung tissue. Their coexpression of the glucocorticoid receptor and core clock components establishes them as a likely interface between humoral suprachiasmatic nucleus output and circadian lung physiology.

Initiation and persistence of warfarin or aspirin in patients with chronic atrial fibrillation in general practice: do the appropriate patients receive stroke prophylaxis?

BACKGROUND

Practice guidelines recommend long-term stroke prophylaxis in patients with chronic atrial fibrillation (cAF).

OBJECTIVES

To examine treatment initiation and persistence and factors that influence the choice of cAF treatment.

PATIENTS/METHODS

This study used the General Practice Research Database, including computerized medical records of general practitioners in the UK. Patients aged 40+ years with cAF after 1 January 2000 were included. Cox proportional hazards regression models evaluated initiation and treatment continuation over time of warfarin and aspirin. Treatment discontinuation was defined as no repeat prescription within a three-month period after the expected end of the treatment course.

RESULTS

The study population included 41 910 cAF patients. Elderly patients (aged 85+) were less likely to start warfarin [relative rate (RR) = 0.16, 95% confidence interval (CI) 0.15-0.18] and more likely to start aspirin (RR = 1.66, 95% CI 1.47-1.88) than patients aged 40-64 years. A history of dementia (RR = 0.28, 95% CI 0.17-0.44) and falls (RR = 0.76, 95% CI 0.70-0.83) also reduced the likelihood of warfarin initiation. Adjusting for age and gender, higher stroke risk (CHADS2 score) was not found to be associated with initiation of warfarin or aspirin contrary to current guidelines recommendations. One-year persistence was 70% for warfarin and 50% for aspirin. Treatment persistence was higher in elderly patients using warfarin and aspirin. A higher CHADS(2) score was associated with improved persistence only with warfarin.

CONCLUSIONS

The low likelihood of patients with cAF in general practice remaining on treatment long-term indicates that not all benefits as observed in clinical trials may be achieved in usual clinical practice.

Persistent endothelial abnormalities and blood?brain barrier leak in primary and secondary progressive multiple sclerosis

Epithelial and endothelial tight junctions are pathologically altered in infectious, inflammatory, neoplastic and other diseases. Previously, we described such abnormalities, associated with serum protein leak, in tight junctions of the blood-brain barrier endothelium, in lesional and normal-appearing white matter (NAWM) in secondary progressive (SP) and acute multiple sclerosis (MS). This work is extended here to lesions and NAWM in primary progressive multiple sclerosis (PPMS) and to cortical grey matter in PPMS and SPMS. Immunocytochemistry and semiquantitative confocal microscopy for the tight junction protein zonula occludens 1 (ZO-1) was performed on snap-frozen sections from PPMS (n = 6) and controls (n = 5). Data on 2103 blood vessels were acquired from active lesions (n = 10), inactive lesions (n = 15), NAWM (n = 42) and controls (n = 20). Data on 1218 vessels were acquired from normal-appearing grey matter (PPMS, 5; SPMS, 6; controls, 5). In PPMS abnormal ZO-1 expression in active white matter lesions and NAWM, was found in 42% and 13% of blood vessels, respectively, comparable to previous data from acute and SPMS. In chronic white matter plaques, however, abnormalities were considerably more frequent (37%) in PPMS than in SPMS. Abnormality was also more frequent in normal-appearing grey matter in SPMS (23%) than in PPMS (10%). In summary, abnormal tight junctions in both SPMS and PPMS are most frequent in active white matter lesions but persist in inactive lesions, particularly in PPMS. Abnormal tight junctions are also common in normal-appearing grey matter in SPMS. Persistent endothelial abnormality with leak (PEAL) is therefore widespread but variably expressed in MS and may contribute to disease progression.

Dihydroimidazophenanthridinium (DIP)-based DNA binding agents with tuneable structures and biological activity

We have synthesised a library of dihydroimidazophenanthridinium cations (DIPs) with large structural diversity (1-29) using a "one-pot" approach. The DNA binding constants of DIPs range from 2x10(4) to 1.3x10(5) M(-1), and the free energies for binding range from -5.9 to -6.40 kcal mol(-1). Viscosity measurements demonstrated that the binding of the compounds caused DNA lengthening, thus signifying binding by intercalation. The cytotoxicities of the compounds were determined by tetrazolium dye-based microtitration assays and showed a large range of values (0.09-11.7 microM). Preliminary molecular modelling studies of the DNA-DIP interactions suggested that the DIP moieties can interact with DNA by intercalation, and some R groups might facilitate binding by minor-groove binding. The results provide insight into how to design biologically active DNA binding agents that can interact in these ways.

Upregulation of ADAM-17 expression in active lesions in multiple sclerosis

ADAM-17, a disintegrin and metalloproteinase, is the major proteinase responsible for the cleavage of membrane-bound tumour necrosis factor (TNF) as well as being an active sheddase of other cytokines, cytokine receptors, growth factors and adhesion molecules. TNF is a major proinflammatory cytokine that has been identified as having a pathogenic role in inflammatory diseases within the CNS including multiple sclerosis (MS). Here we report the cellular origin and distribution of ADAM-17 expression within clinically and neuropathologically confirmed MS and normal control white matter, assessed by immunohistochemistry, western blotting and PCR. ADAM-17 expression was associated with the blood vessel endothelium, activated macrophages/microglia and parenchymal astrocytes in MS white matter. Increased levels of ADAM-17 immunoreactivity were displayed in active lesions with evidence of recent myelin breakdown. Further studies into the functional role of ADAM-17 in the pathogenesis of MS and other inflammatory conditions are required.

Differential expression of ADAMTS-1, -4, -5 and TIMP-3 in rat spinal cord at different stages of acute experimental autoimmune encephalomyelitis

Experimental autoimmune encephalomyelitis (EAE) is an animal model of inflammatory demyelination, a pathological event common to multiple sclerosis (MS). During CNS inflammation there are alterations in the extracellular matrix (ECM). A Disintegrin and Metalloproteinase with Thrombospondin motifs (ADAMTS)-1, -4 and -5 are proteases present in the CNS, which are able to cleave the aggregating chondroitin sulphate proteoglycans, aggrecan, phosphacan, neurocan and brevican. It is therefore important to investigate changes in their expression in different stages of EAE induction. We have investigated expression of ADAMTS-1, -4, -5 and tissue inhibitor of metalloproteinase (TIMP)-3, by real-time RT-PCR. We have also examined protein expression of ADAMTS-1, -4 and -5 by western blotting and immunocytochemistry in spinal cord from animals at different stages of disease progression. Our study demonstrated a decrease in ADAMTS-4 mRNA and protein expression. TIMP-3 was decreased at the mRNA level although protein levels were increased in diseased animals compared to controls. Our study identifies changes in ADAMTS expression during the course of CNS inflammation which may contribute to ECM degradation and disease progression.

Highly stable phenanthridinium frameworks as a new class of tunable DNA binding agents with cytotoxic properties

A new class of cytotoxic heteroaromatic cations is presented, based on the dihydro-imidazo-phenanthridinium framework (DIP), that have affinity for DNA and cytotoxicity toward cancerous cells. The DIP framework is particularly tunable due to the flexible synthetic methodology. Furthermore, the central moiety has proved to be very stable to hydrolysis and reduction compared to other phenanthridinium-based agents.

Using smart card technology to monitor the eating habits of children in a school cafeteria: 1. Developing and validating the methodology

OBJECTIVE

The aim of the study was to test the feasibility of using smart card technology to track the eating behaviours of nearly a thousand children in a school cafeteria.

METHODS

Within a large boys' school a smart card based system was developed that was capable of providing a full electronic audit of all the individual transactions that occurred within the cafeteria. This dataset was interfaced to an electronic version of the McCance and Widdowson composition of foods dataset. The accuracy of the smart card generated data and the influence of portion size and wastage were determined empirically during two 5-day trials.

RESULTS

The smart card system created succeeded in generating precise data on the food choices made by hundreds of children over an indefinite time period. The data was expanded to include a full nutrient analysis of all the foods chosen. The accuracy of this information was only constrained by the limitations facing all food composition research, e.g. variations in recipes, portion sizes, cooking practices, etc. Although technically possible to introduce wastage correction factors into the software, thereby providing information upon foods consumed, this was not seen as universally practical.

CONCLUSION

The study demonstrated the power of smart card technology for monitoring food/nutrient choice over limitless time in environments such as school cafeterias. The strengths, limitations and applications of such technology are discussed.