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• Cyto-nuclear conflicts occurred in Stewartia s. l. phylogeny. • Hartia was nested in Stewartia s.s. with the basal S. malacodendron in America. • Introgression was prevailing in shallow phylogeny with a consistent backbone. • Ancient co-distribution and dispersal contributed to introgression in Asian. Phylogenetic analyses using diverse datasets can yield conflicting inference of evolutionary history. Phylogenetic conflicts observed in both animal and plant systems have often been explained by two competing (but not mutually exclusive) hypotheses, i.e., hybridization vs. incomplete lineage sorting (ILS). The likelihood of either process contributing to phylogenetic conflict in a given group is context-dependent, involving attributes of life history, distribution, and phylogeny, among others. Here we explore phylogenetic conflict in Stewartia s.l. , a genus with ca. 20 species of trees and shrubs from the tea family (Theaceae) disjunctly distributed between eastern Asia (EAS) and eastern North America (ENA). We use both restriction-site associated DNA sequencing (RAD-seq) and complete plastome sequence data to reconstruct the phylogeny of the group using concatenation and coalescence approaches. Our results indicate strong conflicts between the topologies reconstructed using nuclear and plastid data. Four-taxon D -statistic (ABBA-BABA) tests detected prevailing signals of introgression. Bayesian Analysis of Macro-evolutionary Mixtures (BAMM) inferred that species diversification occurred in the middle to late Miocene. Ancestral range reconstructions indicated co-distribution of ancestral species (represented by internal nodes) for both the Hartia clade (in southern China) and the EAS Stewartia s.s. clade (Japan Archipelago and the Yangtze Valley of China). The latter clade experienced multiple events of dispersal and vicariance during its diversification history. Ancient introgressive hybridization following species diversification in the mid- to late-Miocene likely caused diverging histories in the nuclear and plastid genomes, leading to phylogenetic conflict in Stewartia s.l. Our study indicates that species diversification driven by both the intensification of the East Asian summer monsoon since the late Miocene and reduced risks of extinction due to frequent dispersal possibly via East China Sea Land Bridge impacted the anomalous species richness between EAS and ENA. Our study highlights the importance of using data from different genomes while reconstructing deep and shallow phylogenies of organisms. [ABSTRACT FROM AUTHOR]

Objective: To evaluate whether abnormal plasma placental growth factor (PlGF) level is associated with adverse neonatal and maternal outcomes.Methods: This was a secondary analysis of the Preeclampsia Triage by Rapid Assay Trial (PETRA), a prospective, multicenter, observational study that enrolled women with suspected preeclampsia. Our analysis included women age 18-45 years with a singleton pregnancy between 20 and 41 weeks of gestation. Plasma collected at enrollment was used for PlGF measurement. Abnormal PlGF was defined as low (100 pg/mL or less) or very low (less than 12 pg/mL). The primary outcomes were composite adverse neonatal and maternal outcomes. We used multivariable Poisson regression models to examine the association between PlGF and outcomes.Results: Of 1,112 women who met the inclusion criteria, plasma PlGF was low in 742 (67%) and very low in 353 (32%). In the cohort, the overall rates of the composite adverse neonatal and maternal outcomes were 6.4% and 4.8%, respectively. Compared with normal PlGF (more than 100 pg/mL), low PlGF was significantly associated with an increased risk of the composite neonatal outcome (9.2% vs 0.8%; adjusted relative risk [aRR] 17.2, 95% CI 5.2-56.3), and the composite maternal outcome (6.2% vs 1.9%; aRR 3.6, 95% CI 1.7-8.0). Very low PlGF was also significantly associated with both neonatal and maternal outcomes. The sensitivity and specificity of low PlGF were 95.8% and 35.3%, respectively, for the composite neonatal outcome, and 86.8% and 34.3% for the composite maternal outcome. Although the positive predictive values were low (9.2% and 6.2%, respectively), the negative predictive value of low PlGF for neonatal and maternal outcomes was 99.2% and 98.1%, respectively.Conclusion: Among women being evaluated for preeclampsia, those with abnormal PlGF are significantly more likely to experience adverse neonatal and maternal outcomes. These outcomes occur infrequently when the PlGF is normal. These findings suggest that PlGF may be useful for risk stratification of women with suspected preeclampsia.Funding Source: No funding was received for this study. The original PETRA study was supported by funding from Alere. [ABSTRACT FROM AUTHOR]