Eclampsia and Postpartum Depression in the Setting of Recurrent Prenatal COVID-19.

Current research suggests COVID-19 in pregnancy is associated with poor maternal and fetal outcomes, although the exact mechanisms remain unclear, and the approach to the management of affected patients presents a distinct challenge to clinicians. We present a case of gestational hypertension, eclampsia, and postpartum depression in a 39-year-old gravida 4, para 0030 (G4P0) pregnant patient following multiple prenatal severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) infections. After a case of coronavirus disease-19 (COVID-19) during her first trimester, the patient received a two-dose mRNA vaccine against SARS-CoV-2. Despite vaccination, she again contracted COVID-19 during her third trimester of pregnancy. She subsequently developed gestational hypertension at 38 weeks necessitating a cesarean section at 38+4 weeks. The patient delivered a healthy neonate, however, her postpartum course was complicated by eclampsia and postpartum depression. This case bolsters current literature and emphasizes the necessity of continued research into the effects of COVID-19 in pregnant and postpartum women.

A Bacterial Phage Tail-like Structure Kills Eukaryotic Cells by Injecting a Nuclease Effector.

Many bacteria interact with target organisms using syringe-like structures called contractile injection systems (CISs). CISs structurally resemble headless bacteriophages and share evolutionarily related proteins such as the tail tube, sheath, and baseplate complex. In many cases, CISs mediate trans-kingdom interactions between bacteria and eukaryotes by delivering effectors to target cells. However, the specific effectors and their modes of action are often unknown. Here, we establish an ex vivo model to study an extracellular CIS (eCIS) called metamorphosis-associated contractile structures (MACs) that target eukaryotic cells. MACs kill two eukaryotic cell lines, fall armyworm Sf9 cells and J774A.1 murine macrophage cells, by translocating an effector termed Pne1. Before the identification of Pne1, no CIS effector exhibiting nuclease activity against eukaryotic cells had been described. Our results define a new mechanism of CIS-mediated bacteria-eukaryote interaction and are a step toward developing CISs as novel delivery systems for eukaryotic hosts.

MicroRNA dynamics during human embryonic stem cell differentiation to pancreatic endoderm.

MicroRNAs (miRNAs) are small non-coding RNAs that have emerged as critical regulators of human embryonic stem cell (hESC) pluripotency and differentiation. Despite the wealth of information about the role individual that miRNAs play in these two processes, there has yet to be a large-scale temporal analysis of the dynamics of miRNA expression as hESCs move from pluripotency into defined lineages. In this report, we used Next Generation Sequencing (NGS) to map temporal expression of miRNAs over ten 24-hour intervals as pluripotent cells were differentiated into pancreatic endoderm. Of the 2042 known human miRNAs, 694 had non-zero expression on all 11 days. Of these 694 miRNAs, 494 showed statistically significant changes in expression during differentiation. Clusters of miRNAs were identified, each displaying unique expression profiles distributed over multiple days. Selected miRNAs associated with pluripotency/differentiation (miR-302/367 and miR-371/372/373) and development/growth (miR-21, miR-25, miR-103, miR-9, and miR-92a) were found to have distinct expression profiles correlated with changes in media used to drive the differentiation process. Taken together, the clustering of miRNAs to identify expression dynamics that occur over longer periods of time (days vs. hours) provides unique insight into specific stages of differentiation. Major shifts in defined stages of hESC differentiation appear to be heavily dependent upon changes in external environmental factors, rather than intrinsic conditions in the cells.