Inconsistency Between Pictures on Baby Diaper Packaging in Europe and Safe Infant Sleep Recommendations.

OBJECTIVE: To describe the level of inconsistency between pictures on baby diaper packaging and safe infant sleep recommendations (SISRs) in Europe. STUDY DESIGN: We attempted to identify all packaging of baby diapers sold in 11 European countries for infants weighing less than 5 kg through internet searches from July 2022 through February 2023. For each type of package, we extracted whether there was a picture depicting a baby, whether the baby was sleeping, and whether the picture of the sleeping baby was inconsistent with ≥1 of 3 SISRs: (i) nonsupine sleeping position, (ii) soft objects or loose bedding, or (iii) sharing a sleep surface with another person. Data were aggregated at the country level, and a random-effects meta-analysis of proportions was used to obtain summary estimates. The outcome was the summary estimate of the proportion of pictures that were inconsistent with SISRs. RESULTS: We identified 631 baby diaper packaging types of which 49% (95% CI: 42-57; n = 311) displayed a picture of a sleeping baby. Among those 311 packages, 79% (95% CI 73-84) were inconsistent with ≥1 SISR, including a nonsupine sleeping position, 45% (95% CI 39-51), soft objects or loose bedding such as pillows or blankets, 51% (95% CI 46-57), and sharing a sleep surface with another person, 10% (95% CI 4-18). CONCLUSIONS: Pictures on baby diaper packaging in Europe are often inconsistent with SISRs. The prevention of sudden unexpected death in infancy requires action from manufacturers and legislators to stop parents' exposure to misleading images that may lead to dangerous practices.

MipZ caps the plus-end of FtsZ polymers to promote their rapid disassembly.

The spatiotemporal regulation of cell division is a fundamental issue in cell biology. Bacteria have evolved a variety of different systems to achieve proper division site placement. In many cases, the underlying molecular mechanisms are still incompletely understood. In this study, we investigate the function of the cell division regulator MipZ from Caulobacter crescentus, a P-loop ATPase that inhibits the polymerization of the treadmilling tubulin homolog FtsZ near the cell poles, thereby limiting the assembly of the cytokinetic Z ring to the midcell region. We show that MipZ interacts with FtsZ in both its monomeric and polymeric forms and induces the disassembly of FtsZ polymers in a manner that is not dependent but enhanced by the FtsZ GTPase activity. Using a combination of biochemical and genetic approaches, we then map the MipZ-FtsZ interaction interface. Our results reveal that MipZ employs a patch of surface-exposed hydrophobic residues to interact with the C-terminal region of the FtsZ core domain. In doing so, it sequesters FtsZ monomers and caps the (+)-end of FtsZ polymers, thereby promoting their rapid disassembly. We further show that MipZ influences the conformational dynamics of interacting FtsZ molecules, which could potentially contribute to modulating their assembly kinetics. Together, our findings show that MipZ uses a combination of mechanisms to control FtsZ polymerization, which may be required to robustly regulate the spatiotemporal dynamics of Z ring assembly within the cell.

Variations in Guidelines for Diagnosis of Child Physical Abuse in High-Income Countries: A Systematic Review.

Importance: The highly variable practices observed regarding the early detection and diagnostic workup of suspected child physical abuse contribute to suboptimal care and could be partially related to discrepancies in clinical guidelines. Objective: To systematically evaluate the completeness, clarity, and consistency of guidelines for child physical abuse in high-income countries. Evidence Review: For this systematic review, national or regional guidelines that were disseminated from 2010 to 2020 related to the early detection and diagnostic workup of child physical abuse in infants aged 2 years or younger by academic societies or health agencies in high-income countries were retrieved. The definitions of sentinel injuries and the recommended diagnostic workup (imaging and laboratory tests) for child physical abuse were compared. Data were analyzed from July 2020 to February 2021. Findings: Within the 20 included guidelines issued in 15 countries, 168 of 408 expected statements (41%) were missing and 10 statements (4%) were unclear. Among 16 guidelines characterizing sentinel injuries, all of them included skin injuries, such as bruises, hematoma, or burns, but only 8 guidelines (50%) included intraoral injuries and fractures. All 20 guidelines agreed on the indication for radiological skeletal survey, head computed tomography, and head magnetic resonance imaging but differed for those of bone scintigraphy, follow-up skeletal survey, spinal magnetic resonance imaging, cranial ultrasonography, chest computed tomography, and abdominal ultrasonography and computed tomography. Additionally, 16 guidelines agreed on exploring primary hemostasis and coagulation but not on the tests to perform, and 8 guidelines (50%) mentioned the need to investigate bone metabolism. Conclusions and Relevance: These findings suggest that guidelines for the diagnosis of child physical abuse in infants were often clear but lacked completeness and were discrepant on major issues. These results may help identify priorities for well-designed original diagnostic accuracy studies, systematic reviews, or an international consensus process to produce clear and standardized guidelines to optimize practices and infant outcomes.

Diagnostic accuracy of rapid nucleic acid tests for group A streptococcal pharyngitis: systematic review and meta-analysis.

BACKGROUND: Acute pharyngitis is one of the most common conditions in outpatient settings and an important source of inappropriate antibiotic prescribing. Rapid antigen detection tests (RADTs) offer diagnosis of group A streptococcus at the point of care but have limited sensitivity. Rapid nucleic acid tests (RNATs) are now available; a systematic review of their accuracy is lacking. OBJECTIVES: To evaluate the accuracy of RNATs in patients with pharyngitis; to explore test-level and study-level factors that could explain variability in accuracy; and to compare the accuracy of RNATs with that of RADTs. DATA SOURCES: MEDLINE, Embase, Web of Science (1990-2020). STUDY ELIGIBILITY CRITERIA: Cross-sectional studies and randomized trials. PARTICIPANTS: Patients with pharyngitis. INDEX TEST/S AND REFERENCE STANDARDS: RNAT commercial kits compared with throat culture. METHODS: We assessed risk of bias and applicability using QUADAS-2. We performed meta-analysis of sensitivity and specificity using the bivariate random-effects model. Variability was explored by subgroup analyses and meta-regression. RESULTS: We included 38 studies (46 test evaluations; 17 411 test results). RNATs were most often performed in a laboratory. The overall methodological quality of primary studies was uncertain because of incomplete reporting. RNATs had a summary sensitivity of 97.5% (95% CI 96.2%-98.3%) and a summary specificity of 95.1% (95% CI 93.6%-96.3%). There was low variability in estimates across studies. Variability in sensitivity and specificity was partially explained by test type (p < 0.05 for both). Sensitivity analyses limited to studies with low risk of bias showed robust accuracy estimates. RNATs were more sensitive than RADTs (13 studies; 96.8% versus 82.3%, p 0.004); there was no difference in specificity (p 0.92). CONCLUSIONS: The high diagnostic accuracy of RNATs may allow their use as stand-alone tests to diagnose group A streptococcus pharyngitis. Based on direct comparisons, RNATs have greater sensitivity than RADTs and equal specificity. Further studies should evaluate RNATs in point-of-care settings.

Molecular architecture of the DNA-binding sites of the P-loop ATPases MipZ and ParA from Caulobacter crescentus.

The spatiotemporal regulation of chromosome segregation and cell division in Caulobacter crescentus is mediated by two different P-loop ATPases, ParA and MipZ. Both of these proteins form dynamic concentration gradients that control the positioning of regulatory targets within the cell. Their proper localization depends on their nucleotide-dependent cycling between a monomeric and a dimeric state and on the ability of the dimeric species to associate with the nucleoid. In this study, we use a combination of genetic screening, biochemical analysis and hydrogen/deuterium exchange mass spectrometry to comprehensively map the residues mediating the interactions of MipZ and ParA with DNA. We show that MipZ has non-specific DNA-binding activity that relies on an array of positively charged and hydrophobic residues lining both sides of the dimer interface. Extending our analysis to ParA, we find that the MipZ and ParA DNA-binding sites differ markedly in composition, although their relative positions on the dimer surface and their mode of DNA binding are conserved. In line with previous experimental work, bioinformatic analysis suggests that the same principles may apply to other members of the P-loop ATPase family. P-loop ATPases thus share common mechanistic features, although their functions have diverged considerably during the course of evolution.

Structural basis for the activation mechanism of the PlcR virulence regulator by the quorum-sensing signal peptide PapR.

The quorum-sensing regulator PlcR is the master regulator of most known virulence factors in Bacillus cereus. It is a helix-turn-helix (HTH)-type transcription factor activated upon binding of its cognate signaling peptide PapR on a tetratricopeptide repeat-type regulatory domain. The structural and functional properties of PlcR have defined a new family of sensor regulators, called the RNPP family (for Rap, NprR, PrgX, and PlcR), in Gram-positive bacteria. To fully understand the activation mechanism of PlcR, we took a closer look at the conformation changes induced upon binding of PapR and of its target DNA, known as PlcR-box. For that purpose we have determined the structures of the apoform of PlcR (Apo PlcR) and of the ternary complex of PlcR with PapR and the PlcR-box from the plcA promoter. Comparison of the apoform of PlcR with the previously published structure of the PlcR-PapR binary complex shows how a small conformational change induced in the C-terminal region of the tetratricopeptide repeat (TPR) domain upon peptide binding propagates via the linker helix to the N-terminal HTH DNA-binding domain. Further comparison with the PlcR-PapR-DNA ternary complex shows how the activation of the PlcR dimer allows the linker helix to undergo a drastic conformational change and subsequent proper positioning of the HTH domains in the major groove of the two half sites of the pseudopalindromic PlcR-box. Together with random mutagenesis experiments and interaction measurements using peptides from distinct pherogroups, this structural analysis allows us to propose a molecular mechanism for this functional switch.