Research ethics committee decision-making in relation to an efficient neonatal trial.

OBJECTIVE: Randomised controlled trials, a gold-standard approach to reduce uncertainties in clinical practice, are growing in cost and are often slow to recruit. We determined whether methodological approaches to facilitate large, efficient clinical trials were acceptable to UK research ethics committees (RECs). DESIGN: We developed a protocol in collaboration with parents, for a comparative-effectiveness, randomised controlled trial comparing two widely used blood transfusion practices in preterm infants. We incorporated four approaches to improve recruitment and efficiency: (i) point-of-care design using electronic patient records for patient identification, randomisation and data acquisition, (ii) short two-page information sheet; (iii) explicit mention of possible inclusion benefit; (iv) opt-out consent with enrolment as the default. With the support of the UK Health Research Authority, we submitted an identical protocol to 12 UK REC. SETTING: RECs in the UK. MAIN OUTCOME: Number of REC granting favourable opinions. RESULTS: The use of electronic patient records was acceptable to all RECs; one REC raised concerns about the short parent information sheet, 10 about inclusion benefit and 9 about opt-out consent. Following responses to queries, nine RECs granted a favourable final opinion and three rejected the application because they considered the opt-out consent process invalid. CONCLUSIONS: A majority of RECs in this study consider the use of electronic patient record data, short information sheets, opt-out consent and mention of possible inclusion benefit to be acceptable in neonatal comparative-effectiveness research. We identified a need for guidance for RECs in relation to opt-out consent processes. These methods provide opportunity to facilitate large randomised controlled trials.

Systematic review: Body composition in children with inflammatory bowel disease.

BACKGROUND: Paediatric inflammatory bowel disease (IBD) is associated with weight loss, growth restriction and malnutrition. Bone mass deficits are well described, little is known about other body composition compartments. AIMS: To define the alterations in non-bone tissue compartments in children with IBD, and explore the effects of demographic and disease parameters. METHODS: A systematic search was carried out in the PubMed (www.ncbi.nlm.nih.gov/pubmed) and Web of Science databases in May 2014 (limitations age <17 years, and composition measurements compared with a defined control population). RESULTS: Twenty-one studies were included in this systematic review, reporting on a total of 1479 children with IBD [1123 Crohn's disease, 243 ulcerative colitis], pooled mean age 13.1 ± 3.2 years, and 34.9% female. Data were highly heterogeneous, in terms of methodology and patients. Deficits in protein-related compartments were reported. Lean mass deficits were documented in 93.6% of Crohn's disease and 47.7% of ulcerative colitis patients when compared with healthy control populations. Lower lean mass was common to both sexes in Crohn's disease and ulcerative colitis, deficits in females with persisted for longer. Fat-related compartment findings were inconsistent, some studies report reductions in body fat in new diagnosis/active Crohn's disease. CONCLUSIONS: It is clear that almost all children with Crohn's disease and half with ulcerative colitis have reduced lean mass, however, body fat alterations are not well defined. To understand what impact this may have on health and disease in children with IBD, further studies are needed to identify in which tissues these deficits lie, and to quantify body fat and its distribution.

Early nutritional determinants of intrahepatocellular lipid deposition in preterm infants at term age.

BACKGROUND: We have previously shown that by term age, preterm infants have elevated intrahepatocellular lipid (IHCL) content and altered regional adiposity, both of which are risk factors for cardiometabolic illness in adult life. Preterm nutritional intake is a plausible determinant of these aberrant trajectories of development. OBJECTIVE: We aimed to establish if macronutritional components of the preterm diet were determinants of IHCL deposition measured at term equivalent age, using (1)H Magnetic Resonance spectroscopy (MRS). METHODS: Prospective observational case-control study in a single UK neonatal unit. (1)H MR spectra were acquired from 18 preterm infants (<32 weeks gestational age at birth) at term age and 31 healthy term infants, who acted as a control group. Neonatal nutritional information was collected from birth to 34(+6) weeks postmenstrual age. RESULTS: IHCL (median, interquartile range) was significantly higher in preterm-at-term infants compared with term-born infants: 0.735, 0-1.46 versus 0.138, 0-0.58; P=0.003. In preterm infants, IHCL was positively correlated with lipid intake in the first week of life (r=0.52, P=0.04). CONCLUSIONS: This study confirms our previous observation of elevated IHCL in preterm infants at term and suggests that early lipid intake may be a determinant. Future work is warranted to establish the clinical relevance and the role of nutritional intervention in attenuating or exacerbating this effect in preterm infants.

A healthy nation: strengthening child health research in the UK.

Despite a general acknowledgment that research in children is necessary and ethical, the evidence base for child-specific treatments is still sparse. We investigated children's biomedical and health services research in the UK in relation to training, infrastructure and activity, research evidence, and visibility. We show that excellent opportunities for career researchers exist through a competitive, national integrated academic training programme, but that the number of academic paediatricians has decreased by 18% between 2000 and 2011, falling from 11·3% to 5·9% of the consultant workforce. The potential for rapid delivery of studies in children through the National Health Service (NHS) is not being realised: clinical trainees are poorly equipped with core research skills; most newly appointed consultant paediatricians have little or no research experience; less than 5% of contracted consultant time supports research; less than 2·5% of the 2 million children seen in the NHS every year are recruited to studies; and ten of the 20 UK children's hospitals do not have a clinical research facility. Support through National Institute for Health Research networks is good for studies into drugs, but inconsistent for non-drug research; less than 5% of registered studies involve children and only one children's biomedical research centre has been allocated funding from 2012. Of the UK annual public and charitable biomedical research expenditure of roughly £2·2 billion, about 5% is directed at child health research. The scant evidence base is impeding the development of clinical guidance and policy-less than 20% of the outputs of the National Institute for Health and Clinical Excellence are applicable to children. Paediatric representation on major research boards is weak. Parent and young people's advocacy is fragmented, and their views are insufficiently heeded by regulatory bodies. The strong UK Government commitment to biomedical research has not been translated fully to research for children. The power of research in children to turn the tide of the growing burden of non-communicable, chronic, adult diseases that have their origins in early life, to benefit the health of an ageing population and future generations, and to reduce health-care costs is inadequately recognised. On the basis of our findings, we make several recommendations to improve early-years research, including the formation of multidisciplinary, cross-institutional groups of clinical and non-clinical child health researchers and their access to diagnostic and laboratory facilities suitable for children; a unified Children's Research Network for drug studies and non-drug studies; regulatory assessment of research that is proportionate and based on consistent national criteria; an expansion of research posts; support for parents' and young people's advocacy; collaboration between children's research charities; improved research training for paediatric trainees; and closer integration of child health research with core NHS activities.

The diabetic pregnancy and offspring blood pressure in childhood: a systematic review and meta-analysis.

AIMS/HYPOTHESIS: Offspring of diabetic mothers have increased risk of the metabolic syndrome in adulthood. Studies examining BP in offspring of diabetic mothers have conflicting conclusions. We performed a systematic review and meta-analysis of studies reporting offspring BP in children born to diabetic mothers. METHODS: Citations were identified in PubMed. Authors were contacted for additional data. Systolic and diastolic BP in offspring of diabetic mothers and controls were compared. Subgroup analysis of type of maternal diabetes and offspring sex were performed. Fixed-effects models were used, and random-effects models where significant heterogeneity was present. Meta-regression was used to test the relationship between offspring systolic BP and prepregnancy BMI. RESULTS: Fifteen studies were included in the review and 13 in the meta-analysis. Systolic BP was higher in offspring of diabetic mothers (mean difference 1.88 mmHg [95% CI 0.47, 3.28]; p = 0.009). Offspring of mothers with gestational diabetes had similar diastolic BP to controls, but higher systolic BP (1.39 mmHg [95% CI 0.00, 2.77]; p = 0.05); results for type 1 diabetes were inconclusive and there were no separate data available on offspring of type 2 diabetic mothers. Male offspring of diabetic mothers had higher systolic BP (2.01 mmHg [95% CI 0.93, 3.10]; p = 0.0003) and diastolic BP (1.12 mmHg [95% CI 0.36, 1.88]; p = 0.004) than controls; in female offspring there was no difference (systolic: 0.54 mmHg [95% CI -1.83, 2.90], p = 0.66; diastolic: 0.51 mmHg [95% CI -1.07, 2.09], p = 0.52). The correlation between offspring systolic BP and maternal prepregnancy BMI was not significant (p = 0.37). CONCLUSIONS/INTERPRETATION: Offspring of diabetic mothers have higher systolic BP than controls. Differences related to sex and type of maternal diabetes require further investigation.

The diabetic pregnancy and offspring BMI in childhood: a systematic review and meta-analysis.

AIMS/HYPOTHESIS: Offspring of mothers with diabetes are at increased risk of metabolic disorders in later life. Increased offspring BMI is a plausible mediator. We performed a systematic review and meta-analysis of studies examining offspring BMI z score in childhood in relation to maternal diabetes. METHODS: Papers reporting BMI z scores for offspring of diabetic (all types, and pre- and during-pregnancy onset) and non-diabetic mothers were included. Citations were identified in PubMed; bibliographies of relevant articles were hand-searched and authors contacted for additional data where necessary. We compared offspring BMI z score with and without adjustment for maternal pre-pregnancy BMI. We performed fixed effect meta-analysis except where significant heterogeneity called for use of a random effects analysis. RESULTS: Data were available from nine studies. In the diabetic group unadjusted mean offspring BMI z score was 0.28 higher (all diabetic mothers vs controls (95% CI 0.09, 0.47; p = 0.004; nine studies; offspring of diabetic mothers n = 927, controls n = 26,384) and with adjustment for maternal pre-pregnancy BMI, 0.07 higher (95% CI -0.15, 0.28; p = 0.54; three studies; offspring of diabetic mothers n = 244, controls n = 11,206). There was no evidence of a difference in offspring BMI z score in relation to type of diabetes (gestational vs type 1, p = 0.95). CONCLUSIONS/INTERPRETATION: Maternal diabetes is associated with increased offspring BMI z score, although this is no longer apparent after adjustment for maternal pre-pregnancy BMI in the limited number of studies in which this is reported. Causal mediators of the effect of maternal diabetes on offspring outcomes remain to be established; we recommend that future research includes adjustment for maternal pre-pregnancy BMI.

Influence of fatty acid profile of total parenteral nutrition emulsions on the fatty acid composition of different tissues of piglets.

Total parenteral nutrition (TPN) studies in human babies of very-low-birth-weight suggest that the lipid emulsions currently available are not optimum for neonatal nutrition. Since fatty acid metabolism in human and pigs is very similar, the present study examines how lipid emulsions used in clinical TPN (i.e. ClinOleic, Intralipid, Lipofundin or Omegaven), with different fatty acid compositions, administered to neonatal piglets for 7 days, influenced their tissue fatty acid composition as compared to those enterally fed with a sow milk replacer. A positive linear relationship was found between the proportion of all individual fatty acids in the lipid emulsions or in the milk replacer versus those in plasma, skeletal muscle, subcutaneous fat, liver, heart, pancreas, stomach or intestine total lipids or in brain phospholipids, the latter showing the lowest correlation coefficient. With the exception of brain, the proportion of either oleic acid or alpha-linolenic acid in the individual tissues was correlated with those present in the corresponding lipid emulsion or milk replacer, whereas the proportion of linoleic acid correlated significantly with all the tissues studied. With the exception of brain phospholipids, both eicosapentaenoic and docosahexaenoic acids were higher in the tissues of piglets receiving Omegaven than in all other groups. In conclusion, with the exception of the brain, fatty acid composition of plasma and different tissues in piglets are strongly influenced by the fatty acid profile of TPN emulsions. Fatty acid composition of brain phospholipids are, however, much less influenced by dietary composition, indicating an active and efficient metabolism that ensures its appropriate composition at this key stage of development.

Identification, using molecular dynamics, of an effector domain of the ras-binding domain of the raf-p74 protein that is uniquely involved in oncogenic ras-p21 signaling.

By comparing the average structures, computed using molecular dynamics, of the ras-binding domain of raf (RBD) bound to activated wild-type ras-p21 and its homologous inhibitory protein, rap-1A, we formerly identified three domains of the RBD that changed conformation between the two complexes, residues 62-76, 97-110, and 111-121. We found that one synthetic peptide, corresponding to RBD residues 97-110, selectively inhibited oncogenic ras-p21-induced oocyte maturation. In this study, we performed molecular dynamics on the Val 12-ras-p21-RBD complex and compared its average structure with that for the wild-type protein. We find that there is a large displacement of a loop involving these residues when the structures of the two complexes are compared. This result corroborates our former finding that the RBD 97-110 peptide inhibits only signal transduction by oncogenic ras-p21 and suggests that oncogenic p21 uses this loop to interact with raf in a unique manner.

Identification of a glutathione-S-transferase effector domain for inhibition of jun kinase, by molecular dynamics.

We have recently found that the glutathione-S-transferase pi-isozyme (GST-pi), a cellular detoxification enzyme, potently and selectively inhibits activation of jun protein by its upstream kinase, jun kinase (JNK). This newly identified regulatory activity of GST-pi is strongly inhibited by a group of agents that inhibit its enzymatic activity. Since loss of enzymatic activity in general does not correlate with loss of regulatory activity, it is likely that inhibitor binding induces changes in the structure of one or more domains of GST that block its interaction with JNK. To identify regions of GST that change conformation on the binding of inhibitors, we have performed molecular dynamics calculations on GST-pi to compute its average structure in the presence and absence of the inhibitor, glutathione sulfonate. Superposition of the two average structures reveals that several regions change local structure depending upon whether the inhibitor is bound or not bound. Two of these regions, residues 36-50 and 194-201, are highly exposed. We have synthesized peptides corresponding to these two segments and find that the 194-201 sequence strongly inhibits the ability of GST-pi to block the in vitro phosphorylation of jun by JNK. These results suggest that this region of GST-pi is critical to its functioning as a newly discovered regulator of signal transduction.

Molecular dynamics analysis of the structures of ras-guanine nucleotide exchange protein (SOS) bound to wild-type and oncogenic ras-p21. Identification of effector domains of SOS.

The X-ray crystal structure of the ras oncogene-encoded p21 protein bound to SOS, the guanine nucleotide exchange-promoting protein, has been determined. We have undertaken to determine if there are differences between the three-dimensional structures of SOS bound to normal and oncogenic (Val 12-p21) proteins. Using molecular dynamics, we have computed the average structures for both complexes and superimposed them. We find four domains of SOS that differ markedly in structure: 631-641, 676-691, 718-729, and 994-1004. Peptides corresponding to these sequences have been synthesized and found to be powerful modulators of oncogenic p21 in cells as described in an accompanying paper. We find that the SOS segment from 809-815 makes contacts with multiple domains of ras-p21 and can facilitate correlated conformational changes in these domains.

Comparative actions of synthetic omega-grammotoxin SIA and synthetic omega-Aga-IVA on neuronal calcium entry and evoked release of neurotransmitters in vitro and in vivo.

The effects of synthetic omega-grammotoxin SIA (omega-GsTxSIA) and synthetic omega-Aga-IVA were tested in in vitro and in vivo neurochemical assays that are reflective of voltage-sensitive calcium channel function. Synthetic omega-GsTx SIA inhibited K(+)-evoked rat and chick synaptosomal 45Ca2+ flux, K(+)-evoked release of [3H]D-aspartate and [3H]norepinephrine from rat hippocampal brain slices and K(+)-evoked release of [3H]norepinephrine from chick cortical brain slices with potency values that were comparable to those found previously with omega-GsTx SIA purified from the venom of the tarantula spider Grammostola spatulata. These results indicate that trace contaminants do not account for the pharmacology of purified omega-GsTx SIA. omega-GsTx SIA caused a complete inhibition of rat synaptosomal 45Ca2+ flux and hippocampal slice [3H]D-aspartate release, whereas omega-Aga-IVA caused a maximal inhibition of approx 75%. omega-GsTx SIA and omega-Aga-IVA caused an identical partial inhibition of K(+)-evoked increases of intracellular calcium in cortical neurons in primary culture. The addition of nitrendipine to either omega-GsTx SIA or omega-Aga-IVA resulted in an additive and virtually complete inhibition of the cortical neuron intracellular calcium response. In in vivo microdialysis studies, the K(+)-evoked release of glutamate from hippocampus of awake freely moving rats was inhibited with the following rank order of potency: omega-conotoxin GVIA > omega-GsTx SIA > omega-Aga-IVA. Complete inhibition of K(+)-evoked hippocampal glutamate release was observed with 300 nM omega-conotoxin GVIA and 3 microM omega-GsTx SIA. In urethane anesthetized rats, omega-CgTx GVIA caused a partial inhibition, whereas omega-GsTx SIA caused a concentration-dependent and complete inhibition, of basal serotonin release in the hippocampus. Therefore, omega-GsTx SIA was shown to inhibit responses that are sensitive to omega-conotoxin GVIA, omega-Aga-IVA and omega-conotoxin MVIIC, consistent with the notion that omega-GsTx SIA inhibits N-, P- and Q-type high threshold voltage-sensitive calcium channels.

The influence of various steroids on the binding of methyltrienolone (R1881) to human placenta: evidence for a second steroid-binding site which stabilizes the R1881 binding site.

Specificity studies of the binding of R1881 to crude placental homogenate gave surprising results in that certain steroids increased the binding of [3H]R1881 rather than displacing it. While data for 'competing', i.e. displacing, steroids were similar to those reported by other authors, there have been no previous reports of increased binding due to added steroids. This increased binding was due mainly to an increase in capacity (about 10-fold). These data suggest that the placental steroid-binding protein is unusual in that there is a second steroid-binding site whose occupancy increases the stability of the protein, thereby increasing its capacity to bind R1881.