RESUMEN
ImportanceProphylactic cyclo-oxygenase inhibitors (COX-Is) such as indomethacin, ibuprofen and acetaminophen may prevent morbidity and mortality in extremely preterm infants (born ≤28 weeks' gestation). However, there is controversy around which COX-I, if any, is the most effective and safest, which has resulted in considerable variability in clinical practice. Our objective was to develop rigorous and transparent clinical practice guideline recommendations for the prophylactic use of COX-I drugs for the prevention of mortality and morbidity in extremely preterm infants. The Grading of Recommendations Assessment, Development and Evaluation evidence-to-decision framework for multiple comparisons was used to develop the guideline recommendations. A 12-member panel, including 5 experienced neonatal care providers, 2 methods experts, 1 pharmacist, 2 parents of former extremely preterm infants and 2 adults born extremely preterm, was convened. A rating of the most important clinical outcomes was established a priori. Evidence from a Cochrane network meta-analysis and a cross-sectional mixed-methods study exploring family values and preferences were used as the primary sources of evidence. The panel recommended that prophylaxis with intravenous indomethacin may be considered in extremely preterm infants (conditional recommendation, moderate certainty in estimate of effects). Shared decision making with parents was encouraged to evaluate their values and preferences prior to therapy. The panel recommended against routine use of ibuprofen prophylaxis in this gestational age group (conditional recommendation, low certainty in the estimate of effects). The panel strongly recommended against use of prophylactic acetaminophen (strong recommendation, very low certainty in estimate of effects) until further research evidence is available.
RESUMEN
Black-capped chickadees (Poecile atricapillus) produce different vocalizations at different times of year: the fee-bee song is produced by males primarily in spring, whereas the chick-a-dee call is produced year-round but most frequently in the fall and winter. We wanted to determine if neural response to playback in auditory regions of the songbird brain varied with season in parallel to production. We captured adult male black-capped chickadees from the wild in either breeding condition or non-breeding condition and within 24-48 h of bringing them into the laboratory setting, played them recordings of either conspecific vocalizations (fee-bee songs or chick-a-dee calls), heterospecific vocalizations (Song Sparrow, Melospiza melodia, song), or silence. We then measured ZENK protein immunoreactivity (Zenk-ir) in caudomedial nidopallium (NCM) and caudomedial mesopallium (CMM), two regions important for perception of conspecific vocalizations. We found that, overall, non-breeding birds had greater Zenk-ir than breeding birds. In addition, we found that birds in non-breeding condition had significantly greater Zenk-ir to heterospecific song than birds in breeding condition, but this difference was not seen in birds that heard conspecific songs or calls. Finally, in NCMd chickadees had greater response to playback of conspecific vocalizations (when combining song and call groups) than playback of heterospecific vocalizations but only while in breeding condition. Our results qualify the claim that Zenk-ir is biased toward conspecific vocalizations, and indicate that specificity of neural response varies with season. Variation could be a result of increased production and perceptual demand in spring, or hormonal changes in breeding birds, possibly because chickadees display vocal plasticity in chick-a-dee calls in the fall, requiring a degree of neural plasticity across seasons.