Prevalence and risk factors of severe postpartum hemorrhage: a retrospective cohort study.

BACKGROUND: Although maternal deaths are rare in developed regions, the morbidity associated with severe postpartum hemorrhage (SPPH) remains a major problem. To determine the prevalence and risk factors of SPPH, we analyzed data of women who gave birth in Guangzhou Medical Centre for Critical Pregnant Women, which received a large quantity of critically ill obstetric patients who were transferred from other hospitals in Southern China. METHODS: In this study, we conducted a retrospective case-control study to determine the prevalence and risk factors for SPPH among a cohort of women who gave birth after 28 weeks of gestation between January 2015 and August 2019. SPPH was defined as an estimated blood loss ≥1000 mL and total blood transfusion≥4 units. Logistic regression analysis was used to identify independent risk factors for SPPH. RESULTS: SPPH was observed in 532 mothers (1.56%) among the total population of 34,178 mothers. Placenta-related problems (55.83%) were the major identified causes of SPPH, while uterine atony without associated retention of placental tissues accounted for 38.91%. The risk factors for SPPH were maternal age < 18 years (adjusted OR [aOR] = 11.52, 95% CI: 1.51-87.62), previous cesarean section (aOR = 2.57, 95% CI: 1.90-3.47), history of postpartum hemorrhage (aOR = 4.94, 95% CI: 2.63-9.29), conception through in vitro fertilization (aOR = 1.78, 95% CI: 1.31-2.43), pre-delivery anemia (aOR = 2.37, 95% CI: 1.88-3.00), stillbirth (aOR = 2.61, 95% CI: 1.02-6.69), prolonged labor (aOR = 5.24, 95% CI: 3.10-8.86), placenta previa (aOR = 9.75, 95% CI: 7.45-12.75), placenta abruption (aOR = 3.85, 95% CI: 1.91-7.76), placenta accrete spectrum (aOR = 8.00, 95% CI: 6.20-10.33), and macrosomia (aOR = 2.30, 95% CI: 1.38-3.83). CONCLUSION: Maternal age < 18 years, previous cesarean section, history of PPH, conception through IVF, pre-delivery anemia, stillbirth, prolonged labor, placenta previa, placental abruption, PAS, and macrosomia were risk factors for SPPH. Extra vigilance during the antenatal and peripartum periods is needed to identify women who have risk factors and enable early intervention to prevent SPPH.

Isolation and functional assessment of a tomato proteinase inhibitor II gene.

A genomic clone encoding a serine proteinase inhibitor II, designated as TPI-2, was isolated from tomato (Lycopersicon esculentum Mill.) seedling. It consisted of a 990 bp upstream regulatory region and a 680 bp transcription region containing an intron. As shown by northern hybridization, mechanical injury activated its expression in roots, stems and leaves, and so did exogenous hormones jasmonic acid (JA) and alpha-Linolenic acid (LA), though abscisic acid (ABA) and NaCl failed to induce its expression. Salicylic acid (SA) was found to inhibit the inducing effect of LA but not those of mechanical injury and JA. As demonstrated experimentally, TPI-2 could be expressed effectively in tobacco cells and the protein products showed insecticidal activity.

Structural analysis and identification of cis-elements of rice osRACD gene.

The osRACD gene correlated with fertility transformation in the photoperiod sensitive genic male sterile rice (PGMR), Nongken 58S, encoded a rice (Oryza sativa L. ssp. japonica) small GTPase belonging to the Rac/Rho family. Inverse PCR was performed to amplify a fragment about 1.4 kb in 5' upstream region of the osRACD promoter. Deletion mutation and gel mobility shift assay characterized two fragments (-799 to -686 nt, and -686 to -431 nt) in the osRACD promoter that could be involved in its transcriptional regulation. When these two deletion fragments were used as probe respectively, a retarded band appeared in the nuclear extracts of fertile 58S rice under short day (58S-SD). Whereas no retarded band was shown in the nuclear extracts of sterile 58S rice under long day (58S-LD). Competition assay indicated that the factors in the retarded bands binding to these two fragments were the same trans-acting factor (termed rice factor, RF). The binding affinity of RF was affected by phosphorylation and was higher in SD-growth rice than that of LD-growth rice.