Inflammation and cytomegalovirus viremia during pregnancy drive sex-differentiated differences in mortality and immune development in HIV-exposed infants

Children who are HIV-exposed but uninfected have increased infectious mortality compared to HIV-unexposed children, raising the possibility of immune abnormalities following exposure to maternal viraemia, immune dysfunction, and co-infections during pregnancy. In a secondary analysis of the SHINE trial in rural Zimbabwe we explored biological pathways underlying infant mortality, and maternal factors shaping immune development in HIV-exposed uninfected infants. Maternal inflammation and cytomegalovirus viraemia were independently associated with infant deaths: mortality doubled for each log10 rise in maternal C-reactive protein (adjusted hazard ratio (aHR) 2.09; 95% CI 1.33-3.27), and increased 1.6-fold for each log10 rise in maternal cytomegalovirus viral load (aHR 1.62; 95% CI 1.11-2.36). In girls, mortality was more strongly associated with maternal C-reactive protein than cytomegalovirus; in boys, mortality was more strongly associated with cytomegalovirus than C-reactive protein. At age one month, HIV-exposed uninfected infants had a distinct immune milieu, characterised by raised soluble CD14 and an altered CD8 + T-cell compartment. Alterations in immunophenotype and systemic inflammation were generally greater in boys than girls. Collectively, these findings show how the pregnancy immune environment in women with HIV underlies mortality and immune development in their offspring in a sex-differentiated manner, and highlights potential new intervention strategies to transform outcomes of HIV-exposed children. ClinicalTrials.gov/NCT01824940.

Vaccine value profile for Klebsiella pneumoniae

Klebsiella pneumoniae causes community- and healthcare-associated infections in children and adults. Globally in 2019, an estimated 1.27 million (95% Uncertainty Interval [UI]: 0.91-1.71) and 4.95 million (95% UI: 3.62-6.57) deaths were attributed to and associated with bacterial antimicrobial resistance (AMR), respectively. K. pneumoniae was the second leading pathogen in deaths attributed to AMR resistant bacteria. Furthermore, the rise of antimicrobial resistance in both community- and hospital-acquired infections is a concern for neonates and infants who are at high risk for invasive bacterial disease. There is a limited antibiotic pipeline for new antibiotics to treat multidrug resistant infections, and vaccines targeted against K. pneumoniae are considered to be of priority by the World Health Organization. Vaccination of pregnant women against K. pneumoniae could reduce the risk of invasive K.pneumoniae disease in their young offspring. In addition, vulnerable children, adolescents and adult populations at risk of K. pneumoniae disease with underlying diseases such as immunosuppression from underlying hematologic malignancy, chemotherapy, patients undergoing abdominal and/or urinary surgical procedures, or prolonged intensive care management are also potential target groups for a K. pneumoniae vaccine. A 'Vaccine Value Profile' (VVP) for K.pneumoniae, which contemplates vaccination of pregnant women to protect their babies from birth through to at least three months of age and other high-risk populations, provides a high-level, holistic assessment of the available information to inform the potential public health, economic and societal value of a pipeline of K. pneumoniae vaccines and other preventatives and therapeutics. This VVP was developed by a working group of subject matter experts from academia, non-profit organizations, public-private partnerships, and multi-lateral organizations, and in collaboration with stakeholders from the WHO. All contributors have extensive expertise on various elements of the K.pneumoniae VVP and collectively aimed to identify current research and knowledge gaps. The VVP was developed using only existing and publicly available information.

Effect of second booster vaccinations and prior infection against SARS-CoV-2 in the UK SIREN healthcare worker cohort

Background

The protection of fourth dose mRNA vaccination against SARS-CoV-2 is relevant to current global policy decisions regarding ongoing booster roll-out. We aimed to estimate the effect of fourth dose vaccination, prior infection, and duration of PCR positivity in a highly-vaccinated and largely prior-COVID-19 infected cohort of UK healthcare workers.

Methods

Participants underwent fortnightly PCR and regular antibody testing for SARS-CoV-2 and completed symptoms questionnaires. A multi-state model was used to estimate vaccine effectiveness (VE) against infection from a fourth dose compared to a waned third dose, with protection from prior infection and duration of PCR positivity jointly estimated.

Findings

1298 infections were detected among 9560 individuals under active follow-up between September 2022 and March 2023. Compared to a waned third dose, fourth dose VE was 13.1% (95% CI 0.9 to 23.8) overall; 24.0% (95% CI 8.5 to 36.8) in the first 2 months post-vaccination, reducing to 10.3% (95% CI -11.4 to 27.8) and 1.7% (95% CI -17.0 to 17.4) at 2-4 and 4-6 months, respectively. Relative to an infection >2 years ago and controlling for vaccination, 63.6% (95% CI 46.9 to 75.0) and 29.1% (95% CI 3.8 to 43.1) greater protection against infection was estimated for an infection within the past 0-6, and 6-12 months, respectively. A fourth dose was associated with greater protection against asymptomatic infection than symptomatic infection, whilst prior infection independently provided more protection against symptomatic infection, particularly if the infection had occurred within the previous 6 months. Duration of PCR positivity was significantly lower for asymptomatic compared to symptomatic infection.

Interpretation

Despite rapid waning of protection, vaccine boosters remain an important tool in responding to the dynamic COVID-19 landscape; boosting population immunity in advance of periods of anticipated pressure, such as surging infection rates or emerging variants of concern.

Funding

UK Health Security Agency, Medical Research Council, NIHR HPRU Oxford, Bristol, and others.

Post-COVID-19 paediatric inflammatory multisystem syndrome: association of ethnicity, key worker and socioeconomic status with risk and severity

OBJECTIVES

Patients from ethnic minority groups and key workers are over-represented among adults hospitalised or dying from COVID-19. In this population-based retrospective cohort, we describe the association of ethnicity, socioeconomic and family key worker status with incidence and severity of Paediatric Inflammatory Multisystem Syndrome Temporally associated with SARS-CoV-2 (PIMS-TS).

SETTING

Evelina London Children's Hospital (ELCH), the tertiary paediatric hospital for the South Thames Retrieval Service (STRS) region.

PARTICIPANTS

70 children with PIMS-TS admitted 14 February 2020-2 June 2020.

OUTCOME MEASURES

Incidence and crude ORs are presented, comparing ethnicity and socioeconomic status of our cohort and the catchment population, using census data and Index of Multiple Deprivation (IMD). Regression is used to estimate the association of ethnicity and IMD with admission duration and requirement for intensive care, inotropes and ventilation.

RESULTS

Incidence was significantly higher in children from black (25.0 cases per 100 000 population), Asian (6.4/100 000) and other (17.8/100 000) ethnic groups, compared with 1.6/100 000 in white ethnic groups (ORs 15.7, 4.0 and 11.2, respectively). Incidence was higher in the three most deprived quintiles compared with the least deprived quintile (eg, 8.1/100 000 in quintile 1 vs 1.6/100 000 in quintile 5, OR 5.2). Proportions of families with key workers (50%) exceeded catchment proportions. Admission length of stay was 38% longer in children from black ethnic groups than white (95% CI 4% to 82%; median 8 days vs 6 days). 9/10 children requiring ventilation were from black ethnic groups.

CONCLUSIONS

Children in ethnic minority groups, living in more deprived areas and in key worker families are over-represented. Children in black ethnic groups had longer admissions; ethnicity may be associated with ventilation requirement.This project was registered with the ELCH audit and service evaluation team, ref. no 11186.

Biomarkers for Disease Severity in Children Infected With Respiratory Syncytial Virus: A Systematic Literature Review

BACKGROUND

Clinical manifestations of respiratory syncytial virus (RSV) infection vary widely from mild, self-limiting illness to severe life-threatening disease. There are gaps in knowledge of biomarkers to objectively define severe disease and predict clinical outcomes.

METHODS

A systematic search was performed, 1945-March 2019 in databases Ovid Medline, Embase, Global health, Scopus, and Web of Science. Risk of bias was assessed using the Cochrane tool.

RESULTS

A total of 25 132 abstracts were screened and studies were assessed for quality, risk of bias, and extracted data; 111 studies met the inclusion criteria. RSV severity was correlated with antibody titers, reduced T and B cells, dysregulated innate immunity, neutrophil mobilization to the lungs and blood, decreased Th1 response, and Th2 weighted shift. Microbial exposures in respiratory tract may contribute to neutrophil mobilization to the lungs of the infants with severe RSV compared with mild RSV disease.

CONCLUSIONS

Although a wide range of biomarkers have been associated with RSV disease severity, robust validated biomarkers are lacking. This review illustrates the broad heterogeneity of study designs and high variability in the definition of severe RSV disease. Prospective studies are required to validate biomarkers. Additional research investigating epigenetics, metabolomics, and microbiome holds promise for novel biomarkers.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Healthcare access for children and families on the move and migrants

BACKGROUND

The United Kingdom (UK) National Health Service (NHS) charging regulations have increasingly restricted migrants' healthcare access, in the context of a wider national policy shift over the past few years intending to create a 'hostile environment' for migrants. With an estimated 144 000 undocumented children living in the UK and increasing public concern that these regulations are negatively impacting migrant health and well-being, as well as contravening international child rights agreements, it has become imperative to understand their implications.

METHODS

A mixed methods digital survey, covering attitudes towards and understanding of UK healthcare charging, and giving space for relevant case submission, was disseminated through communications channels of the Royal College of Paediatrics and Child Health (RCPCH) to their members. Quantitative data were analysed on Stata, and basic proportions were calculated for each response proportion. Qualitative data were analysed using a framework analysis approach.

RESULTS

There were 200 responses, from a range of healthcare professional backgrounds. The majority were not confident in interpreting and applying the charging regulations. One-third (34%) reported examples of the charging regulations impacting patient care, analysis of which elicited seven key themes. Our survey gathered 18 cases of migrants being deterred from accessing healthcare, 11 cases of healthcare being delayed or denied outright, and 12 cases of delay in accessing care leading to worse health outcomes, including two intrauterine deaths.

DISCUSSION

Our results describe a range of harms arising from the current NHS charging regulations contributing to delays in or denials of healthcare, due to patients' fear of charging or immigration enforcement, including potential deportation, and confusion around entitlements. This harm affects individual patients, the migrant community and the NHS - often in multiple simultaneous ways. Many patients eligible for NHS care, such as trafficking victims, are not being identified as such. We found the current charging regulations to be unworkable, and that harm could not be eliminated simply through improved awareness or implementation.

Outcomes beyond hospital discharge in infants and children with viral meningitis: A systematic review

Viruses are the commonest cause of childhood meningitis, but outcomes beyond hospital discharge are poorly described. We undertook a systematic literature review of long-term outcomes following paediatric viral meningitis. A search was carried out using MEDLINE, Embase, and Cochrane Review for studies from 1 January 1990 to 31 December 2018. Studies were included where specific outcome measures were available beyond hospital discharge for children <16 years old with viral meningitis. In total, 3588 papers were identified of which 14 were eligible for inclusion. Four studies reported outcomes in children with nonenterovirus 71 meningitis. A US study of 16 cases demonstrated subtle language difficulties at 3-year follow-up in infants in contrast to an Australian study, which revealed no impairment in language. A Fijian study showed that two out of eight cases had sensorineural hearing loss compared with none in a UK cohort of 668 infants. Three studies evaluated outcomes of enterovirus 71 meningitis in China and Taiwan, two showed cases recovered without sequelae, while one demonstrated an increased risk of attention deficit hyperactivity disorder. Two studies including 141 cases of human parechovirus revealed no evidence of neurodevelopmental sequelae. Conversely, an Australian study demonstrated neurodevelopmental sequelae in 11 out of 77 infants with parechovirus meningitis. Most studies identified in this review demonstrated a high proportion of good clinical outcomes following viral meningitis. However, the data are limited, so robustly conducted neurodevelopmental studies are warranted to inform the evidence-based management of viral meningitis beyond hospital discharge.

Discrimination, harassment and non-reporting in UK medical education

CONTEXT

Discrimination and harassment create a hostile environment with deleterious effects on student well-being and education. In this study, we aimed to: (i) measure prevalences and types of discrimination and harassment in one UK medical school, and (ii) understand how and why students report them.

METHODS

The study used a mixed-methods design. A medical school population survey of 1318 students was carried out in March 2014. Students were asked whether they had experienced, witnessed or reported discrimination or harassment and were given space for free-text comments. Two focus group sessions were conducted to elicit information on types of harassment and the factors that influenced reporting. Proportions were analysed using the Wilson score method and associations tested using chi-squared and regression analyses. Qualitative data were subjected to framework analysis. Degrees of convergence between data were analysed.

RESULTS

A total of 259 (19.7%) students responded to the survey. Most participants had experienced (63.3%, 95% confidence interval [CI]: 57.3-69.0) or witnessed (56.4%, 95% CI: 50.3-62.3) at least one type of discrimination or harassment. Stereotyping was the form most commonly witnessed (43.2%, 95% CI: 37.4-49.3). In the qualitative data, reports of inappropriate joking and invasion of personal space were common. Black and minority ethnic students had witnessed and religious students had experienced a greater lack of provision (χ²  = 4.73, p = 0.03 and χ²  = 4.38, p = 0.04, respectively). Non-heterosexual students had experienced greater joking (χ²  = 3.99, p = 0.04). Students with disabilities had experienced more stereotyping (χ²  = 13.5, p < 0.01). Female students and students in clinical years had 2.6 (95% CI: 1.3-5.3) and 3.6 (95% CI: 1.9-7.0) greater odds, respectively, of experiencing or witnessing any type of discrimination or harassment. Seven of 140 survey respondents had reported incidents (5.0%, 95% CI: 2.4-10.0). Reporting was perceived as ineffective and as potentially victimising of the reporter.

CONCLUSIONS

Harassment and discrimination are prevalent in this sample and associated with gender, ethnicity, sexuality, disability and year group. Reporting is rare and perceived as ineffective. These findings have informed local developments, future strategies and the development of a national prevention policy.

Respiratory syncytial virus seasonality and its implications on prevention strategies

With maternal and infant vaccines against respiratory syncytial virus (RSV) in development, it is timely to consider how the deployment of these vaccines might vary according to local RSV disease seasonality. In temperate regions RSV infection is predictably limited to a period of 3 to 5 months, while in tropical regions disease seasonality is often both more variable and more prolonged. Accordingly, in tropical regions a year-round immunisation schedule for both maternal and infant immunisation might be appropriate. In contrast, in temperate regions the benefit of year-round maternal immunisation would be heavily dependent on the duration of protection this provided, potentially necessitating a strategy directed at children due to be born in the months immediately prior to the RSV season. This review will consider the impact of seasonality on maternal and infant immunisation strategies against RSV, and the potential of an alternative approach of passive immunisation for all infants immediately prior to the RSV season.

Infectious causes of microcephaly: epidemiology, pathogenesis, diagnosis, and management

Microcephaly is an important sign of neurological malformation and a predictor of future disability. The 2015-16 outbreak of Zika virus and congenital Zika infection brought the world's attention to links between Zika infection and microcephaly. However, Zika virus is only one of the infectious causes of microcephaly and, although the contexts in which they occur vary greatly, all are of concern. In this Review, we summarise important aspects of major congenital infections that can cause microcephaly, and describe the epidemiology, transmission, clinical features, pathogenesis, management, and long-term consequences of these infections. We include infections that cause substantial impairment: cytomegalovirus, herpes simplex virus, rubella virus, Toxoplasma gondii, and Zika virus. We highlight potential issues with classification of microcephaly and show how some infants affected by congenital infection might be missed or incorrectly diagnosed. Although Zika virus has brought the attention of the world to the problem of microcephaly, prevention of all infectious causes of microcephaly and appropriately managing its consequences remain important global public health priorities.

Interventions to Improve the Response of Professionals to Children Exposed to Domestic Violence and Abuse: A Systematic Review

Exposure of children to domestic violence and abuse (DVA) is a form of child maltreatment with short- and long-term behavioural and mental health impact. Health care professionals are generally uncertain about how to respond to domestic violence and are particularly unclear about best practice with regards to children's exposure and their role in a multiagency response. In this systematic review, we report educational and structural or whole-system interventions that aim to improve professionals' understanding of, and response to, DVA survivors and their children. We searched 22 bibliographic databases and contacted topic experts for studies reporting quantitative outcomes for any type of intervention aiming to improve professional responses to disclosure of DVA with child involvement. We included interventions for physicians, nurses, social workers and teachers. Twenty-one studies met the inclusion criteria: three randomised controlled trials (RCTs), 18 pre-post intervention surveys. There were 18 training and three system-level interventions. Training interventions generally had positive effects on participants' knowledge, attitudes towards DVA and clinical competence. The results from the RCTs were consistent with the before-after surveys. Results from system-level interventions aimed to change organisational practice and inter-organisational collaboration demonstrates the benefit of coordinating system change in child welfare agencies with primary health care and other organisations. Implications for policy and research are discussed. © 2015 The Authors. Child Abuse Review published by John Wiley & Sons Ltd. 'We searched 22 bibliographic databases and contacted topic experts'.

KEY PRACTITIONER MESSAGES

We reviewed published evidence on interventions aimed at improving professionals' practice with domestic violence survivors and their children.Training programmes were found to improve participants' knowledge, attitudes and clinical competence up to a year after delivery.Key elements of successful training include interactive discussion, booster sessions and involving specialist domestic violence practitioners.Whole-system approaches aiming to promote coordination and collaboration across agencies appear promising but require funding and high levels of commitment from partners. 'Training programmes were found to improve participants' knowledge, attitudes and clinical competence up to a year after delivery'.

Cholinergic interactions between donepezil and prucalopride in human colon: potential to treat severe intestinal dysmotility

BACKGROUND AND PURPOSE

Cholinesterase inhibitors such as neostigmine are used for acute colonic pseudo-obstruction, but cardio-bronchial side-effects limit use. To minimize side-effects, lower doses could be combined with a 5-HT4 receptor agonist, which also facilitates intestinal cholinergic activity. However, safety concerns, especially in the elderly, require drugs with good selectivity of action. These include the AChE inhibitor donepezil (used for Alzheimer's disease, with reduced cardio-bronchial liability) and prucalopride, the first selective, clinically available 5-HT4 receptor agonist. This study examined their individual and potential synergistic activities in human colon.

EXPERIMENTAL APPROACH

Neuronally mediated muscle contractions and relaxations of human colon were evoked by electrical field stimulation (EFS) and defined phenotypically as cholinergic, nitrergic or tachykinergic using pharmacological tools; the effects of drugs were determined as changes in 'area under the curve'.

KEY RESULTS

Prucalopride increased cholinergically mediated contractions (EC50 855 nM; 33% maximum increase), consistent with its ability to stimulate intestinal motility; donepezil (477%) and neostigmine (2326%) had greater efficacy. Concentrations of donepezil (30-100 nM) found in venous plasma after therapeutic doses had minimal ability to enhance cholinergic activity. However, donepezil (30 nM) together with prucalopride (3, 10 μM) markedly increased EFS-evoked contractions compared with prucalopride alone (P = 0.04). For example, the increases observed with donepezil and prucalopride 10 μM together or alone were, respectively, 105 ± 35%, 4 ± 6% and 35 ± 21% (n = 3-7, each concentration).

CONCLUSIONS AND IMPLICATIONS

Potential synergy between prucalopride and donepezil activity calls for exploration of this combination as a safer, more effective treatment of colonic pseudo-obstruction.

Regionally dependent neuromuscular functions of motilin and 5-HT₄ receptors in human isolated esophageal body and gastric fundus

BACKGROUND

Motilin agonists promote human gastric motility and cholinergic activity, but excitatory and inhibitory actions are reported in the esophagus. The effect of 5-HT₄ agonists in esophagus is also unclear. Perhaps the use of drugs with additional actions explains the variation. The aim, therefore, was to examine how motilin and prucalopride, selective motilin and 5-HT₄ receptor agonists, modulate neuromuscular functions in human esophagus and gastric fundus.

METHODS

Electrical field stimulation (EFS) evoked nerve-mediated contractions of circular and longitudinal muscle from human esophageal body and circular muscle from gastric fundus.

KEY RESULTS

In esophageal circular muscle EFS evoked brief contraction, followed by another contraction on termination of EFS, each prevented by atropine. Nitric oxide synthase inhibition facilitated contraction during EFS and the overall contraction became monophasic. In esophagus longitudinal muscle and gastric fundus, EFS evoked cholinergically mediated, monophasic contractions, attenuated by simultaneous nitrergic activation. Motilin (100-300 nM) reduced esophagus circular muscle contractions during EFS, unaffected by L-NAME or apamin. Motilin 300 nM also reduced EFS-evoked contractions of longitudinal muscle. Similar concentrations of motilin facilitated cholinergic activity in the fundus and increased baseline muscle tension. Prucalopride facilitated EFS-evoked contractions in esophagus (tested at 30 μM) and fundus (0.1-30 μM).

CONCLUSIONS & INFERENCES

Selective motilin and 5-HT₄ agonists have different, region-dependent abilities to modulate human esophageal and stomach neuromuscular activity, exemplified by weak inhibition (motilin) or excitation (5-HT₄) in esophageal body and excitation for both in stomach. In different patients with motility dysfunctions, motilin and 5-HT₄ agonists may reduce gastro-esophageal reflux in different ways.

Drugs acting at 5-HT4 , D2 , motilin, and ghrelin receptors differ markedly in how they affect neuromuscular functions in human isolated stomach

BACKGROUND

Progress in identifying safer, effective drugs to increase gastric emptying is impeded by failed clinical trials. One potential reason for failure is lack of translation from animal models to the human condition. To make progress, the actions of existing drugs and new therapeutic candidates need to be understood in human isolated stomach.

METHODS

Neuromuscular activities were evoked in human gastric antrum circular muscle by electrical field stimulation (EFS), defined phenotypically using pharmacological tools.

KEY RESULTS

EFS evoked cholinergically mediated contractions, attenuated by simultaneous nitrergic activation. The 5-HT4 receptor agonist/D2 antagonist metoclopramide and the selective 5-HT4 agonist prucalopride, facilitated contractions in the absence (respectively, Emax 95 ± 29% and 42 ± 9%, n = 3-6 each concentration) and presence (139 ± 38%, 55 ± 13%, n = 3-5) of the NO synthase inhibitor L-NAME, without affecting submaximal contractions to carbachol; the 5-HT4 antagonist SB204070 prevented facilitation by metoclopramide 100 μM (respectively, -5 (range -26 to 34) and 167 (12-1327)% in presence and absence; n = 5-6). The selective motilin receptor agonist camicinal provided considerably greater facilitation (478 (12-2080)% at 30 μM, n = 8). Domperidone (0.001-100 μM; n = 3-6) and acylated or des-acylated ghrelin (1-300 nM; n = 2-4) had no consistent activity, even with protease inhibitors.

CONCLUSIONS & INFERENCES

5-HT4 receptor agonists show different efficacies. Motilin receptor activation has greater potential to increase gastric emptying, whereas ghrelin and D2 receptor antagonism have no direct activity. Drugs stimulating human gastric motility directly can act regardless of disease mechanisms, whereas drugs without direct activity but an ability to block nausea/vomiting may be effective only if these symptoms exist.

Translational neuropharmacology: the use of human isolated gastrointestinal tissues

Translational sciences increasingly emphasize the measurement of functions in native human tissues. However, such studies must confront variations in patient age, gender, genetic background and disease. Here, these are discussed with reference to neuromuscular and neurosecretory functions of the human gastrointestinal (GI) tract. Tissues are obtained after informed consent, in collaboration with surgeons (surgical techniques help minimize variables) and pathologists. Given the difficulties of directly recording from human myenteric neurones (embedded between muscle layers), enteric motor nerve functions are studied by measuring muscle contractions/relaxations evoked by electrical stimulation of intrinsic nerves; responses are regionally dependent, often involving cholinergic and nitrergic phenotypes. Enteric sensory functions can be studied by evoking the peristaltic reflex, involving enteric sensory and motor nerves, but this has rarely been achieved. As submucosal neurones are more accessible (after removing the mucosa), direct neuronal recordings are possible. Neurosecretory functions are studied by measuring changes in short-circuit current across the mucosa. For all experiments, basic questions must be addressed. Because tissues are from patients, what are the controls and the influence of disease? How long does it take before function fully recovers? What is the impact of age- and gender-related differences? What is the optimal sample size? Addressing these and other questions minimizes variability and raises the scientific credibility of human tissue research. Such studies also reduce animal use. Further, the many differences between animal and human GI functions also means that human tissue research must question the ethical validity of using strains of animals with unproved translational significance.

Motilin: towards a new understanding of the gastrointestinal neuropharmacology and therapeutic use of motilin receptor agonists

The gastrointestinal hormone motilin has been known about for >40 years, but after identification of its receptor and subsequent development of new tools and methods, a reappraisal of its actions is required. Firstly, it is important to note that motilin and ghrelin receptors are members of the same family (similar genomic organization, gastrointestinal distribution and abilities to stimulate gastrointestinal motility), yet each fails to recognize the ligand of the other; and whereas ghrelin and ghrelin receptors are widespread outside the gastrointestinal tract, motilin and its receptors are largely restricted to the gastrointestinal tract. Secondly, although some studies suggest motilin has activity in rodents, most do not, and receptor pseudogenes exist in rodents. Thirdly, motilin preferentially operates by facilitating enteric cholinergic activity rather than directly contracting the muscle, despite the relatively high expression of receptor immunoreactivity in muscle. This activity is ligand-dependent, with short-lasting actions of motilin contrasting with longer-lasting actions of the non-selective and selective motilin receptor agonists erythromycin and GSK962040. Finally, the use of erythromycin (also an antibiotic drug) to treat patients requiring acceleration of gastric emptying has led to concerns over safety and potential exacerbation of antibiotic resistance. Replacement motilin receptor agonists derived from erythromycin (motilides) have been unsuccessful. New, non-motilide, small molecule receptor agonists, designed to minimize self-desensitization, are now entering clinical trials for treating patients undergoing enteral feeding or with diabetic gastroparesis. Thus, for the translational pharmacologist, the study of motilin illustrates the need to avoid overreliance on artificial systems, on structural information and on animal studies.

LINKED ARTICLES

This article is part of a themed section on Neuropeptides. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2013.170.issue-7.

Regional- and agonist-dependent facilitation of human neurogastrointestinal functions by motilin receptor agonists

BACKGROUND AND PURPOSE

Delayed gastric emptying is poorly managed. Motilin agonists are potential treatments but inadequate understanding into how enteric nerve functions are stimulated compromises drug/dose selection. Resolution is hampered by extreme species dependency so methods were developed to study human gastrointestinal neuromuscular activities and the neurobiology of motilin.

EXPERIMENTAL APPROACH

Protocols to study neuromuscular activities were developed for different regions of human stomach and intestine (71 patients) using circular muscle preparations and electrical field stimulation (EFS) of intrinsic nerves. Other tissues were fixed for immunohistochemistry.

KEY RESULTS

EFS evoked contractions and/or relaxations via cholinergic and nitrergic neurons, with additional tachykinergic activity in colon; these were consistent after 154 min (longer if stored overnight). Motilin 1-300 nM and the selective motilin agonist GSK962040 0.1-30 µM acted pre-junctionally to strongly facilitate cholinergic contractions of the antrum (E(max) ≈ 1000% for motilin), with smaller increases in fundus, duodenum and ileum; high concentrations increased baseline muscle tension in fundus and small intestine. There were minimal effects in the colon. In the antrum, cholinergic facilitation by motilin faded irregularly, even with peptidase inhibitors, whereas facilitation by GSK962040 was long lasting. Motilin receptor immunoreactivity was identified in muscle and myenteric plexus predominantly in the upper gut, co-expressed with choline acetyltransferase in neurons.

CONCLUSIONS AND IMPLICATIONS

Motilin and GSK962040 strongly facilitated cholinergic activity in the antrum, with lower activity in fundus and small intestine only. Facilitation by motilin was short lived, consistent with participation in migrating motor complexes. Long-lasting facilitation by GSK962040 suggests different receptor interactions and potential for clinical evaluation.

GSK962040: a small molecule motilin receptor agonist which increases gastrointestinal motility in conscious dogs

BACKGROUND

GSK962040, a small molecule motilin receptor agonist, was identified to address the need for a safe, efficacious gastric prokinetic agent. However, as laboratory rodents lack a functional motilin system, studies in vivo have been limited to a single dose, which increased defecation in rabbits. Motilin agonists do not usually increase human colonic motility, so gastric prokinetic activity needs to be demonstrated.

METHODS

The effect of intravenous GSK962040 on gastro-duodenal motility was assessed in fasted dogs implanted with strain gauges. Activity was correlated with blood plasma concentrations of GSK962040 (measured by HPLC-MS/MS) and potency of GSK962040 at the dog recombinant receptor [using a Fluorometric Imaging Plate Reader (Molecular Devices, Wokingham, UK) after expression in HEK293 cells].

KEY RESULTS

GSK962040 activated the dog motilin receptor (pEC(50) 5.79; intrinsic activity 0.72, compared with [Nle(13) ]-motilin). In vivo, GSK962040 induced phasic contractions, the duration of which was dose-related (48 and 173 min for 3 and 6 mg kg(-1) ), driven by mean plasma concentrations >1.14 μmol L(-1) . After the effects of GSK962040 faded, migrating motor complex (MMC) activity returned. Migrating motor complex restoration was unaffected by 3 mg kg(-1) GSK962040 but at 6 mg kg(-1) , MMCs returned 253 min after dosing, compared with 101 min after saline (n=5 each).

CONCLUSIONS & INFERENCES

The results are consistent with lower potency for agonists at the dog motilin receptor, compared with humans. They also define the doses of GSK962040 which stimulate gastric motility. Correlation of in vivo and in vitro data in the same species, together with plasma concentrations, guides further studies and translation to other species.

Writing for publication

As the number of medical students increases, the competition for foundation and specialist training posts becomes more intense. One way to strengthen your application is to show the selection committee that you have written articles that have been peer reviewed and published in respected journals. This article is intended to guide you through the process of writing for publication.

Global changes in the hippocampal proteome following exposure to an enriched environment

Exposure to an enriched environment promotes neurochemical, structural and neurophysiological changes in the brain and is associated with enhanced synaptic plasticity and improved hippocampal-dependent learning. Using a global proteomics-based approach we have now been able to reveal the altered expression of a diverse range of hippocampal proteins following exposure to an enriched environment. Male Hooded Lister rats (8 weeks) were subjected to a 6-week regimen in which they were housed in either non-enriched (open field) or enriched conditions (toys, wheels etc.). Whole protein extracts from stratum pyramidale and stratum radiatum of area CA1 were then isolated and subjected to differential gel electrophoresis [McNair K, Davies CH, Cobb SR (2006) Plasticity-related regulation of the hippocampal proteome. Eur J Neurosci 23(2):575-580]. Of the 2469 resolvable protein spots detected in this study, 42 spots (1.7% of the detectable proteome) derived from predominantly somatic fractions and 32 proteins spots from dendritic fractions (1.3% of detectable proteome) were significantly altered in abundance following exposure to an enriched environment (somatic: 14 increased/28 decreased abundance, range -1.5 to +1.4-fold change; dendritic: 16 increased, 16 decreased abundance, range -1.6 to +3.0-fold change). Following in-gel tryptic digestion and Maldi-Tof/Q-star mass spectrometry, database searching revealed the identity of 50 protein spots displaying environmental enrichment-related modulation of expression. Identified proteins belonged to a variety of functional classes with gene ontology analysis revealing the majority (>70%) of regulated proteins to be part of the energy metabolism, cytoplasmic organization/biogenesis and signal transduction processes.

Tillering in grain sorghum over a wide range of population densities: identification of a common hierarchy for tiller emergence, leaf area development and fertility

Most studies of tiller development have not related the physiological and morphological features of each culm to its subsequent fertility. This introduces problems when trying to account for the effects of tillering on yield in crop models. The objective of this study was to detect the most likely early determinants of tiller fertility in sorghum by identifying hierarchies for emergence, fertility and grain number of tillers over a wide range of assimilate availabilities. Emergence, phenology, leaf area development and dry weight partitioning were quantified weekly for individual tillers and main culms of tillering and uniculm plants grown at one of four densities, from two to 16 plants m(-2). For a given plant in any given density, the same tiller hierarchy applied for emergence of tillers, fertility of the emerged tillers and their subsequent grain number. These results were observed over a range of tiller fertility rates (from 7 to 91%), fertile tiller number per plant at maturity (from 0.2 to 4.7), and tiller contribution to grain yield (from 5 to 78 %). Tiller emergence was most probably related to assimilate supply and light quality. Development, fertility and contribution to yield of a specific tiller were highly dependent on growing conditions at the time of tiller emergence, particularly via early leaf area development of the tiller, which affected its subsequent leaf area accumulation. Assimilate availability in the main culm at the time of tiller emergence was the most likely early determinant of subsequent tiller fertility in this study.

Sensitivity of Shah, Vanclay and Cooper's modified Barthel Index

OBJECTIVE

To investigate whether Shah, Vanclay and Cooper's modification of the Barthel Index improved its sensitivity to change.

DESIGN

Correlational study.

SETTING

School of Occupational Therapy at Auckland Institute of Technology, Auckland, New Zealand.

SUBJECTS

One hundred subjects requiring rehabilitation following a stroke.

MAIN OUTCOME MEASURES

Change in function which was measured using Shah, Vanclay and Cooper's (1989) modified Barthel Index and walking speed over 10 metres.

RESULTS

Five statistical analyses were undertaken, none of which demonstrated clear superiority of one measure over the other.

CONCLUSIONS

The study did not indicate the modified Barthel Index to be more sensitive to change than the 20-point Barthel Index for this population. The statistical analysis strategies utilized are recommended for similar studies.

Increasing self-efficacy through empowerment: preoperative education for orthopaedic patients

PURPOSE

To examine whether patients who received an empowerment model of education for preoperative orthopaedic teaching had improved outcomes compared to patients who received the traditional education.

DESIGN

An experimental (empowerment teaching method) group vs. comparison (traditional teaching method) group posttest design.

SAMPLE

Seventy-four patients undergoing elective orthopaedic surgery.

METHODS

Following the preoperative teaching session, patients in both groups completed a questionnaire designed to measure their perceptions of the teaching (empowerment) and self-efficacy (belief in their ability to carry out perioperative tasks). A chart audit and phone interview was done after discharge to assess length of stay, pain management, complications, and patient perceptions of the ability to complete perioperative tasks.

FINDINGS

Patients in the empowerment group felt the educational approach was more empowering and had significantly higher self-efficacy scores than those in the traditional teaching group. There was much less variation in empowerment and self-efficacy scores in the empowerment group. The empowerment group reported feeling greater confidence in performing perioperative tasks. There were no differences in length of stay, complications or pain control.

CONCLUSION

Use of an empowerment teaching approach enabled patients to become more confident in their ability to carry out perioperative tasks and become a more integral part of the preoperative teaching process.

IMPLICATIONS FOR NURSING RESEARCH

The theoretical model will be used to structure other educational programs and guide research. More sensitive measures of complications and pain control should be considered for future studies.

Older adults and healthy lifestyle issues: results of a community study

AIM

To discover sources of information about, levels of understanding of, and degrees of commitment to a healthy lifestyle on the part of elderly people in the community as a preliminary to mounting health promotion and education initiatives.

METHOD

In 1992 500 people aged 60 and over were surveyed anonymously using a 33 item questionnaire. This sought information on a wide range of health and lifestyle issues in older age. The material in this paper refers to only four of the questions asked, namely those relating to sources of, knowledge of, and interest in information on health and ageing.

RESULTS

Doctors were perceived to be the most important sources of health information (89% of respondents rating them as "very" or "moderately" important). Relatives/friends and books/magazines were the next most important sources (56 and 55% respectively). High levels of misinformation about lifestyle issues were revealed. Whilst 85+% of respondents answered correctly that smoking was deleterious and strong social ties advantageous to good health in old age there was confusion about causes of osteoporosis, use of vitamins, likelihood of developing dementia and even the importance of exercise. This has implications for the content of health promotion programmes. Contrary to previously published research, we found no correlation between educational or socioeconomic status or gender, and knowledge about health issues and healthy lifestyles.

CONCLUSION

Studies of this type clearly have the ability to provide a range of information which ought to be available to those responsible for the planning of health promotion and education initiatives for older adults.

Geographical variations in the organisation of general practice

AIMS

To describe organisational characteristics of New Zealand general practice and to investigate inter-regional variations in these characteristics.

METHODS

Data were collected by standardised questionnaires from general practitioners in Auckland, Waikato and Taranaki. The Waikato data were collected in July-August 1991 by postal survey, the Taranaki data were collected May-June 1992 by postal survey and the Auckland data were collected December 1990 to January 1991 by face-to-face interview.

RESULTS

The response rates were Auckland 98% (167/171), Waikato 84% (185/220) and Taranaki 79% (79/100). There were significantly more overseas trained graduates in rural areas than in urban areas. Average practice size was 2.3 full time equivalent doctors, with each 100 doctors employing 71 nurses and 77 receptionists. The number of patients seen per week ranged from 109-141. Almost all (95%) general practitioners operated appointment systems. One in five general practitioners had patients in private hospitals, and more than half (58%) had patients in rest homes. At the time of interview, 29% of Auckland general practitioners used computers in their practices compared with over 50% in Waikato and Taranaki (p < 0.05). A smaller proportion of Auckland general practitioners had access to age/sex registers and fewer Auckland general practitioners had a recall system. Of Auckland general practitioners with recall systems, a greater proportion used them for mammograms, blood pressure and lipid measurements compared with elsewhere.

CONCLUSIONS

There are some significant regional variations in the functional characteristics of general practice in New Zealand which should be taken into account when planning primary care services in different regions. Should budget holding and managed care be introduced, computerised practices will be required. This will have significant resource implications.

A profile of the 7500 people in aged-care institutions in Auckland

A study was carried out in 1988 to describe the residents and patients of aged-care institutions in Auckland against which future measures, including planned changes in licensing and funding, could be made. Information was collected for each patient in every hospital (public and private) and each resident in all old people's homes in the Auckland region between January and June 1988. Of the 7516 people surveyed (99.4% response rate), 70% were residents in old people's homes, 25% were patients in private hospitals and 6% were cared for in the public hospital sector. Of the people surveyed, 71% were women. The average age of women, 82 years, was 6.5 years older than that of men. Three-quarters of all women and 44% of men in care were widowed. Women had a higher rate of admission to institutions than did men with almost one in two women and one in four men in the age group 85 years and over being in long term care. Rates of institutionalisation for Maoris and Pacific Islanders were the same as for Europeans. The majority of elderly people received regular contact and concern from family members. This study has demonstrated that Auckland has a higher proportion of the elderly population (7.6% of the population 65 years and over) in long term care compared with other areas of New Zealand.

Clinical application of the Children's Action Tendency Scale

The clinical usefulness of a previously validated self-report measure of children's assertiveness was examined for two white school-age samples ( ns = 18 and 17; 6 to 14 yr. old) referred for training in group social skills. Subscale scores of a clinical sample supported the norms of the validation samples but the relationship of these scores to parental and self-report measures of self-esteem appeared equivocal. Use with a hyperkinetic sample showed the scale's sensitivity to treatment, but faking good during individual testing may be a problem with such children.

Use of Burks' behavior rating scale with a referred population

The behavior of 106 children referred for social skills training was assessed by parental ratings. The resulting local norms supported the clinical sensitivity of Burks' scale. Independent therapists' and parents' ratings of a sub-sample produced inadequate inter-rater reliability.