Informed consent rates for neonatal randomized controlled trials in low- and lower middle-income versus high-income countries: A systematic review.

OBJECTIVE: Legal, ethical, and regulatory requirements of medical research uniformly call for informed consent. We aimed to characterize and compare consent rates for neonatal randomized controlled trials in low- and lower middle-income countries versus high-income countries, and to evaluate the influence of study characteristics on consent rates. METHODS: In this systematic review, we searched MEDLINE, EMBASE and Cochrane for randomized controlled trials of neonatal interventions in low- and lower middle-income countries or high-income countries published 01/01/2013 to 01/04/2018. Our primary outcome was consent rate, the proportion of eligible participants who consented amongst those approached, extracted from the article or email with the author. Using a generalised linear model for fractional dependent variables, we analysed the odds of consenting in low- and lower middle-income countries versus high-income countries across control types and interventions. FINDINGS: We screened 3523 articles, yielding 300 eligible randomized controlled trials with consent rates available for 135 low- and lower middle-income country trials and 65 high-income country trials. Median consent rates were higher for low- and lower middle-income countries (95.6%; interquartile range (IQR) 88.2-98.9) than high-income countries (82.7%; IQR 68.6-93.0; p<0.001). In adjusted regression analysis comparing low- and lower middle-income countries to high-income countries, the odds of consent for no placebo-drug/nutrition trials was 3.67 (95% Confidence Interval (CI) 1.87-7.19; p = 0.0002) and 6.40 (95%CI 3.32-12.34; p<0.0001) for placebo-drug/nutrition trials. CONCLUSION: Neonatal randomized controlled trials in low- and lower middle-income countries report consistently higher consent rates compared to high-income country trials. Our study is limited by the overrepresentation of India among randomized controlled trials in low- and lower middle-income countries. This study raises serious concerns about the adequacy of protections for highly vulnerable populations recruited to clinical trials in low- and lower middle-income countries.

Prospective Assessment of Pill-Swallowing Ability in Pediatric Patients.

Difficulty with pill-swallowing ability (PSA) is common in children, yet formal evaluation is rare. The objective of this study was to prospectively evaluate and compare PSA of inpatient and outpatient children using the Pediatric Oral Medications Screener. We identified children aged 3 to 17 years admitted to a general or subspecialty pediatric service at a university hospital or outpatient clinic. Using the Pediatric Oral Medications Screener, patients were observed swallowing 3 different-sized placebo pills (5 mm tablet, 10 mm tablet, and 22 mm capsule), and subjective measures were assessed from parents and children. We analyzed 47 inpatients and 62 outpatients. Sixteen percent of patients could not swallow any pill, 11% only swallowed the small pill, 14% swallowed up to the medium pill, and 60% swallowed all formulations. After controlling for multiple factors, inpatients had superior PSA compared with outpatients ( P = .004). These results suggest targeted inpatient screening and widespread outpatient screening would likely identify children with reduced PSA.

A Prospective Comparison of Transcutaneous and Serum Bilirubin Within Brief Time Intervals.

The American Academy of Pediatrics recommends screening newborns ≥35 weeks' gestation with total serum bilirubin (TSB) or transcutaneous bilirubin (TcB) to detect hyperbilirubinemia. Retrospective studies show TcB measurements strongly correlate with TSB; however, few prospective trials document this relationship. Furthermore, Dräger's newest TcB instrument, JM-105, remains unstudied in the United States. We measure TcB on foreheads and sternums of newborns using JM-105 and Bilichek devices within 30 minutes of TSB measurement. We find best overall TcB/TSB correlation with JM-105 on the sternum (mean TcB-TSB difference: -0.21 ± 1.15 mg/dL). Correlations between paired measurements for TcB on the sternum using JM-105 were 0.93 for all TSB levels (n = 178), 0.82 for TSB > 10 (n = 19), 0.69 for TSB > 12 (n = 11), and 0.52 for TSB > 15 (n = 6). TcB accuracy via JM-105 on the sternum significantly differed among races ( P < .001). For 5% of paired measurements, TcB with JM-105 on the sternum underestimated TSB by ≥2 mg/dL, and for <1% by ≥3 mg/dL.

Hierarchical regulation of photosynthesis gene expression by the oxygen-responsive PrrBA and AppA-PpsR systems of Rhodobacter sphaeroides.

In the facultatively phototrophic proteobacterium Rhodobacter sphaeroides, formation of the photosynthetic apparatus is oxygen dependent. When oxygen tension decreases, the response regulator PrrA of the global two-component PrrBA system is believed to directly activate transcription of the puf, puh, and puc operons, encoding structural proteins of the photosynthetic complexes, and to indirectly upregulate the photopigment biosynthesis genes bch and crt. Decreased oxygen also results in inactivation of the photosynthesis-specific repressor PpsR, bringing about derepression of the puc, bch, and crt operons. We uncovered a hierarchical relationship between these two regulatory systems, earlier thought to function independently. We also more accurately assessed the spectrum of gene targets of the PrrBA system. First, expression of the appA gene, encoding the PpsR antirepressor, is PrrA dependent, which establishes one level of hierarchical dominance of the PrrBA system over AppA-PpsR. Second, restoration of the appA transcript to the wild-type level is insufficient for rescuing phototrophic growth impairment of the prrA mutant, whereas inactivation of ppsR is sufficient. This suggests that in addition to controlling appA transcription, PrrA affects the activity of the AppA-PpsR system via an as yet unidentified mechanism(s). Third, PrrA directly activates several bch and crt genes, traditionally considered to be the PpsR targets. Therefore, in R. sphaeroides, the global PrrBA system regulates photosynthesis gene expression (i) by rigorous control over the photosynthesis-specific AppA-PpsR regulatory system and (ii) by extensive direct transcription activation of genes encoding structural proteins of photosynthetic complexes as well as genes encoding photopigment biosynthesis enzymes.

In vitro and in vivo analysis of the role of PrrA in Rhodobacter sphaeroides 2.4.1 hemA gene expression.

The hemA gene codes for one of two synthases in Rhodobacter sphaeroides 2.4.1 which catalyze the formation of 5-aminolevulinic acid. We have examined the role of PrrA, a DNA binding protein that is associated with the metabolic switch between aerobic growth and anoxygenic photosynthetic growth, in hemA expression and found that hemA transcription is directly activated by PrrA. Using electrophoretic mobility shift assays and DNase I protection assays, we have mapped two binding sites for PrrA within the hemA upstream sequences, each of which contains an identical 9-bp motif. Using lacZ transcription reporter plasmids in wild-type strain 2.4.1 and PrrA- mutant strain PRRA2, we showed that PrrA was required for maximal expression. We also found that the relative impacts of altering DNA sequences within the two binding sites are different depending on whether cells are growing aerobically or anaerobically. This reveals a greater level of complexity associated with PrrA-mediated regulation of transcription than has been heretofore described. Our findings are of particular importance with respect to those genes regulated by PrrA having more than one upstream binding site. In the case of the hemA gene, we discuss possibilities as to how these new insights can be accommodated within the context of what has already been established for hemA transcription regulation in R. sphaeroides.

Mutational analysis of the C-terminal domain of the Rhodobacter sphaeroides response regulator PrrA.

The Rhodobacter sphaeroides response regulator PrrA directly activates transcription of genes necessary for energy conservation at low O2 tensions and under anaerobic conditions. It is proposed that PrrA homologues contain a C-terminal DNA-binding domain (PrrA-CTD) that lacks significant amino acid sequence similarity to those found in other response regulators. To test this hypothesis, single amino acid substitutions were created at 12 residues in the PrrA-CTD. These mutant PrrA proteins were purified and tested for the ability to be phosphorylated by the low-molecular-mass phosphate donor acetyl phosphate, to activate transcription and to bind promoter DNA. Each mutant PrrA protein accepted phosphate from 32P-labelled acetyl phosphate. At micromolar concentrations of acetyl phosphate-treated wild-type PrrA, a single 20 bp region in the PrrA-dependent cycA P2 promoter was protected from DNase I digestion. Of the mutant PrrA proteins tested, only acetyl phosphate-treated PrrA-N168A and PrrA-I177A protected cycA P2 from DNase I digestion at similar protein concentrations compared to wild-type PrrA. The use of in vitro transcription assays with the PrrA-dependent cycA P2 and puc promoters showed that acetyl phosphate-treated PrrA-N168A produced transcript levels similar to that of wild-type PrrA at comparable protein concentrations. Using concentrations of acetyl phosphate-treated PrrA that are saturating for the wild-type protein, PrrA-H170A and PrrA-I177A produced <45 % as much transcript as wild-type PrrA. Under identical conditions, the remaining mutant PrrA proteins produced little or no detectable transcripts from either promoter in vitro. Explanations are presented for why these amino acid side chains in the PrrA-CTD are important for its ability to activate transcription.