Parallel Evolution in Predatory Bdellovibrio sp. NC01 during Long-Term Coculture with a Single Prey Strain.

Experimental evolution provides a powerful tool for examining how Bdellovibrio evolves in response to unique selective pressures associated with its predatory lifestyle. We tested how Bdellovibrio sp. NC01 adapts to long-term coculture with Pseudomonas sp. NC02, which is less susceptible to predation compared to other Gram-negative bacteria. Analyzing six replicate Bdellovibrio populations across six time points spanning 40 passages and 2,880 h of coculture, we detected 30 to 40 new mutations in each population that exceeded a frequency of 5%. Nonsynonymous substitutions were the most abundant type of new mutation, followed by small indels and synonymous substitutions. After completing the final passage, we detected 20 high-frequency (>75%) mutations across all six evolved Bdellovibrio populations. Eighteen of these alter protein sequences, and most increased in frequency rapidly. Four genes acquired a high-frequency mutation in two or more evolved Bdellovibrio populations, reflecting parallel evolution and positive selection. The genes encode a sodium/phosphate cotransporter family protein (Bd2221), a metallophosphoesterase (Bd0054), a TonB family protein (Bd0396), and a hypothetical protein (Bd1601). Tested prey range and predation efficiency phenotypes did not differ significantly between evolved Bdellovibrio populations and the ancestor; however, all six evolved Bdellovibrio populations demonstrated enhanced starvation survival compared to the ancestor. These results suggest that, instead of evolving improved killing of Pseudomonas sp. NC02, Bdellovibrio evolved to better withstand nutrient limitation in the presence of this prey strain. The mutations identified here point to genes and functions that may be important for Bdellovibrio adaptation to the different selective pressures of long-term coculture with Pseudomonas. IMPORTANCE Bdellovibrio attack and kill Gram-negative bacteria, including drug-resistant pathogens of animals and plants. This lifestyle is unusual among bacteria, and it imposes unique selective pressures on Bdellovibrio. Determining how Bdellovibrio evolve in response to these pressures is valuable for understanding the mechanisms that govern predation. We applied experimental evolution to test how Bdellovibrio sp. NC01 evolved in response to long-term coculture with a single Pseudomonas strain, which NC01 can kill, but with low efficiency. Our experimental design imposed different selective pressures on the predatory bacteria and tracked the evolutionary trajectories of replicate Bdellovibrio populations. Using genome sequencing, we identified Bdellovibrio genes that acquired high-frequency mutations in two or more populations. Using phenotype assays, we determined that evolved Bdellovibrio populations did not improve their ability to kill Pseudomonas, but rather are better able to survive starvation. Overall, our results point to functions that may be important for Bdellovibrio adaptation.

Storage of Medications: A Survey of Families in the Pediatric Emergency Department.

OBJECTIVES: To evaluate caregivers' practice of prescription medication storage, particularly of opioid medications, as well as to provide educational materials to families about the opioid crisis. METHODS: Caregivers of patients in a pediatric emergency department were asked to participate in a survey about medication storage practices and beliefs, focusing on opioid medications. Data were collected through a survey documenting demographic data along with knowledge and behaviors of medication storage. Brief education about the US opioid crisis and safe storage was provided. RESULTS: In total, 233 families participated; 3 families declined; 11.5% of caregivers reported storing prescribed medications in a locked or latched place, although most store them "out of reach." Most believed their child or children's friends could not easily access their medications (81.8%). Families who did not keep their medications in locked or latched places had never thought about it (39.7%). In total, 33% of respondents were unaware of the opioid crisis; 87.4% of caregivers said they would use a medication lock box if given one. CONCLUSIONS: Many caregivers are not aware of the opioid crisis and do not keep opioid medications locked up. Half of the caregivers surveyed stated they "never thought about" locking up medications. Most parents would use a lock box if given to them. This opens the door to further study, education, and interventions.

Putative avian teeth from the Late Cretaceous of Alberta, Canada, are more likely from crocodilians.

Isolated teeth, previously referred to Aves, are more common than other bird fossils from the Late Cretaceous of Alberta. However, there are no known morphological synapomorphies that distinguish isolated bird teeth, and features of these teeth are generally shared with those of non-avian theropods and crocodilians. Here, specimens ranging from Late Santonian to Late Maastrichtian in age are described and qualitatively categorized into morphotypes, most of which strongly resemble teeth of extant juvenile and some fossil crocodilians. Variation within this sample of teeth may therefore reflect the heterodont dentition of crocodilians, rather than avian species diversity. Quantitative analysis Principal Component Analysis was mostly uninformative, with limited overlap between putative avian teeth and those of known Cretaceous birds, crocodilians, and non-avian theropods. The reassignment of these putative avian teeth to Crocodylia has important ramifications for our understanding of the evolutionary history of Cretaceous birds.

Delivery timing for the opioid-exposed infant.

BACKGROUND: The prevalence of opioid use disorder and medication-assisted treatment in pregnancy is increasing. Compared with term infants, preterm infants have a lower incidence of neonatal opioid withdrawal syndrome. It is unknown whether early term delivery compared with full or late-term delivery decreases the risk of neonatal opioid withdrawal syndrome. OBJECTIVE: This study aimed to compare the neonatal outcomes among opioid-exposed infants born in the early, full, and late-term periods. STUDY DESIGN: This was a retrospective cohort study of opioid-exposed pregnancies delivering at a single center from 2010 to 2017 at ≥37 weeks gestation. Participants with multiple gestations or fetal anomalies were excluded. Maternal opioid exposure was defined as prescription (including medication-assisted treatment) or nonprescription opioid use or a positive urine drug screen in pregnancy for opiates. The primary outcome was a neonatal composite of respiratory distress syndrome, neonatal sepsis, neonatal seizures, hypoxic ischemic encephalopathy, jaundice requiring treatment, 5-minute Apgar <5, neonatal intensive care unit admission, neonatal opioid withdrawal syndrome, or neonatal death. The secondary outcomes included individual components of the primary outcome, birthweight, need for and length of neonatal opioid withdrawal syndrome treatment, length of hospital admission, and maximum Finnegan scores. Early (37-<39), full (39-<41), and late (41-<42 weeks) term groups were defined by the American College of Obstetricians and Gynecologists. RESULTS: Of 399 infants, 136 (34.1%), 229 (57.4%), and 34 (8.5%) were born in the early, full, and late-term periods, respectively. Two hundred and seventy patients (67.7%) received medication-assisted treatment for opioid use disorder, and the baseline characteristics were similar in all the groups except for history of intranasal heroin use, positive urine toxicology screen for heroin or any opiates, and delivery indication (P<.05). The primary composite outcome occurred in 313 (78.4%) neonates, and 296 (74.2%) neonates had neonatal opioid withdrawal syndrome. More than half (219 [54.9%]) of opioid-exposed neonates were admitted to the neonatal intensive care unit, and 160 (40.1%) required pharmacologic neonatal opioid withdrawal syndrome treatment for a mean duration of almost 3 weeks (19.0±16.1 days). There were no significant differences in the primary composite outcome, incidence of neonatal opioid withdrawal syndrome, or other secondary outcomes (except birthweight) between neonates born in the early, full, or late-term periods. CONCLUSION: Although neonatal morbidity was frequent among opioid-exposed neonates, the incidence and severity of neonatal opioid withdrawal syndrome or other neonatal outcomes were not different between neonates delivered in the early, full, and late-term periods, suggesting that opioid-exposed infants may not benefit from early term delivery.