The ESKAPE mobilome contributes to the spread of antimicrobial resistance and CRISPR-mediated conflict between mobile genetic elements

Mobile genetic elements (MGEs) mediate the shuffling of genes among organisms. They contribute to the spread of virulence and antibiotic resistance (AMR) genes in human pathogens, such as the particularly problematic group of ESKAPE pathogens. Here, we performed the first systematic analysis of MGEs, including plasmids, prophages, and integrative and conjugative/mobilizable elements (ICEs/IMEs), across all ESKAPE pathogens. We found that different MGE types are asymmetrically distributed across these pathogens, and that most horizontal gene transfer (HGT) events are restricted by phylum or genus. We show that the MGEs proteome is involved in diverse functional processes and distinguish widespread proteins within the ESKAPE context. Moreover, anti-CRISPRs and AMR genes are overrepresented in the ESKAPE mobilome. Our results also underscore species-specific trends shaping the number of MGEs, AMR, and virulence genes across pairs of conspecific ESKAPE genomes with and without CRISPR-Cas systems. Finally, we observed that CRISPR spacers found on prophages, ICEs/IMEs, and plasmids have different targeting biases: while plasmid and prophage CRISPRs almost exclusively target other plasmids and prophages, respectively, ICEs/IMEs CRISPRs preferentially target prophages. Overall, our study highlights the general importance of the ESKAPE mobilome in contributing to the spread of AMR and mediating conflict among MGEs.     

Perinatal outcomes of midwife-led care,stratified by medical risk: a retrospective cohort study from British Columbia (2008–2018)

Background:Anecdotal evidence suggests that the profile of midwifery clients in British Columbia has changed over the past 20 years and that midwives are increasingly caring for clients with moderate to high medical risk. We sought to compare perinatal outcomes with a registered midwife as the most responsible provider (MRP) versus outcomes among clients with physicians as their MRP across medical risk strata.Methods:This retrospective cohort study (2008–2018) used data from the BC Perinatal Data Registry. We included all births that had a family physician, obstetrician or midwife listed as the MRP (n = 425 056) and stratified the analysis by pregnancy risk status (low, moderate or high) according to an adapted perinatal risk scoring system. We estimated differences in outcomes between MRP groups by calculating adjusted absolute and relative risks.Results:The adjusted absolute and relative risks of adverse neonatal outcomes were consistently lower among those who chose midwifery care across medical risk strata, compared with clients who had a physician as MRP. Midwifery clients experienced higher rates of spontaneous vaginal births, vaginal births after cesarean delivery and breastfeeding initiation, and lower rates of cesarean deliveries and instrumental births, with no increase in adverse neonatal outcomes. We observed an increased risk of oxytocin induction among high-risk birthers with a midwife versus an obstetrician as MRP.Interpretation:Our findings suggest that compared with other providers in BC, midwives provide safe primary care for clients with varied levels of medical risk. Future research might examine how different practice and remuneration models affect clinical outcomes, client and provider experiences, and costs to the health care system.

In British Columbia, registered midwives are autonomous, primary health care providers, regulated and integrated into the publicly funded health care system. Midwives typically work in small-team continuity-of-care models, providing medical care during pregnancy, birth and up to 3 months postpartum in the community and in hospitals. Midwives hold hospital privileges and consult with physician colleagues as medically indicated.Since the regulation of midwifery in BC in 1998, the number of pregnant people who are attended by midwives during birth has steadily increased, from 4.8% in 2004/05¹ to 15.6% in 2019/20.² In 2018/19, 1 in 4 childbearing people in BC (25.4%) had a midwife involved in their care at some point during their pregnancy, birth or postpartum period.²Several studies have examined the safety of midwifery care in BC after regulation. Janssen and colleagues analyzed the outcomes of low-risk clients from 2000 to 2004, providing important evidence for the safety of midwife-attended planned home births in the early years after regulation.³ Other researchers have described good perinatal outcomes for subsets of midwifery clients in BC, including those residing in rural areas⁴ and those planning vaginal births after cesarean (VBAC) at home.⁵ However, these studies focused on subsamples of childbearing people or did not use recent data.The benefits of midwife-led care for clients with more complex needs are beginning to emerge in BC. Using BC perinatal data, McRae and colleagues^6,7 demonstrated that those affected by low socioeconomic position, substance use and mental illness had lower odds of small-for-gestational-age babies, pretermbirth and low-birth-weight babies when they were cared for by midwives antenatally rather than by physicians.This analysis is part of a larger mixed-methods study that aimed to better understand the changing profile of midwifery clients in BC and the implications this has for education, research and practice. The goal of the current analysis is to present complete and recent data from all births in BC that had a midwife, family physician or obstetrician listed as the most responsible provider (MRP). Specifically, we sought to document neonatal and maternal outcomes of childbearing people who had a mid-wife as their MRP compared with those who had a physician as the MRP, with similar medical risk profiles.     

Faster cytotoxicity with age: Increased perforin and granzyme levels in cytotoxic CD8 + T cells boost cancer cell elimination

A variety of intrinsic and extrinsic factors contribute to the altered efficiency of CTLs in elderly organisms. In particular, the efficacy of antiviral CD8⁺ T cells responses in the elderly has come back into focus since the COVID‐19 pandemic outbreak. However, the exact molecular mechanisms leading to alterations in T cell function and the origin of the observed impairments have not been fully explored. Therefore, we investigated whether intrinsic changes affect the cytotoxic ability of CD8⁺ T cells in aging. We focused on the different subpopulations and time‐resolved quantification of cytotoxicity during tumor cell elimination. We report a surprising result: Killing kinetics of CD8⁺ T cells from elderly mice are much faster than those of CD8⁺ T cells from adult mice. This is true not only in the total CD8⁺ T cell population but also for their effector (T_EM) and central memory (T_CM) T cell subpopulations. TIRF experiments reveal that CD8⁺ T cells from elderly mice possess comparable numbers of fusion events per cell, but significantly increased numbers of cells with granule fusion. Analysis of the cytotoxic granule (CG) content shows significantly increased perforin and granzyme levels and turns CD8⁺ T cells of elderly mice into very efficient killers. This highlights the importance of distinguishing between cell‐intrinsic alterations and microenvironmental changes in elderly individuals. Our results also stress the importance of analyzing the dynamics of CTL cytotoxicity against cancer cells because, with a simple endpoint lysis analysis, cytotoxic differences could have easily been overlooked.     

Characterizing the Propagation of Uterine Electrophysiological Signals Recorded with a Multi-Sensor Abdominal Array in Term Pregnancies

The objective of this study was to quantify the number of segments that have contractile activity and determine the propagation speed from uterine electrophysiological signals recorded over the abdomen. The uterine magnetomyographic (MMG) signals were recorded with a 151 channel SARA (SQUID Array for Reproductive Assessment) system from 36 pregnant women between 37 and 40 weeks of gestational age. The MMG signals were scored and segments were classified based on presence of uterine contractile burst activity. The sensor space was then split into four quadrants and in each quadrant signal strength at each sample was calculated using center-of-gravity (COG). To this end, the cross-correlation analysis of the COG was performed to calculate the delay between pairwise combinations of quadrants. The relationship in propagation across the quadrants was quantified and propagation speeds were calculated from the delays. MMG recordings were successfully processed from 25 subjects and the average values of propagation speeds ranged from 1.3–9.5 cm/s, which was within the physiological range. The propagation was observed between both vertical and horizontal quadrants confirming multidirectional propagation. After the multiple pairwise test (99% CI), significant differences in speeds can be observed between certain vertical or horizontal combinations and the crossed pair combinations. The number of segments containing contractile activity in any given quadrant pair with a detectable delay was significantly higher in the lower abdominal pairwise combination as compared to all others. The quadrant-based approach using MMG signals provided us with high spatial-temporal information of the uterine contractile activity and will help us in the future to optimize abdominal electromyographic (EMG) recordings that are practical in a clinical setting.