SummaryThe stator-force generator that drives Na + -dependent motility in alkaliphilic Bacillus pseudofirmus OF4 is identified here as MotPS, MotAB-like proteins with genes that are downstream of the ccpA gene, which encodes a major regulator of carbon metabolism. B. pseudofirmus OF4 was only motile at pH values above 8. Disruption of motPS resulted in a non-motile phenotype, and motility was restored by transformation with a multicopy plasmid containing the motPS genes. Purified and reconstituted MotPS from B. pseudofirmus OF4 catalysed amiloride analogue-sensitive Na + translocation. In contrast to B. pseudofirmus , Bacillus subtilis contains both MotAB and MotPS systems. The role of the motPS genes from B. subtilis in several motility-based behaviours was tested in isogenic strains with intact motAB and motPS loci, only one of the two mot systems or neither mot system. B. subtilis MotPS (BsMotPS) supported Na + -stimulated motility, chemotaxis on soft agar surfaces and biofilm formation, especially after selection of an up-motile variant. BsMotPS also supported motility in agar soft plugs immersed in liquid; motility was completely inhibited by an amiloride analogue. BsMotPS did not support surfactin-dependent swarming on higher concentration agar surfaces.These results indicate that BsMotPS contributes to biofilm formation and motility on soft agar, but not to swarming, in laboratory strains of B. subtilis in which MotAB is the dominant stator-force generator. BsMotPS could potentially be dominant for motility in B. subtilis variants that arise in particular niches.

Cytoreductive surgery (CRS) with or without hyperthermic intraperitoneal chemotherapy (HIPEC) is associated with improved survival for patients with colorectal peritoneal metastases (CR-PM). However, the role of neoadjuvant chemotherapy (NAC) prior to CRS-HIPEC is poorly understood. A retrospective review of adult patients with CR-PM who underwent CRS+/-HIPEC from 2000-2017 was performed. Among 298 patients who underwent CRS+/-HIPEC, 196 (65.8%) received NAC while 102 (34.2%) underwent surgery first (SF). Patients who received NAC had lower peritoneal cancer index score (12.1 + 7.9 vs. 14.3 + 8.5, p = 0.034). There was no significant difference in grade III/IV complications (22.4% vs. 16.7%, p = 0.650), readmission (32.3% vs. 23.5%, p = 0.114), or 30-day mortality (1.5% vs. 2.9%, p = 0.411) between groups. NAC patients experienced longer overall survival (OS) (median 32.7 vs. 22.0 months, p = 0.044) but similar recurrence-free survival (RFS) (median 13.8 vs. 13.0 months, p = 0.456). After controlling for confounding factors, NAC was not independently associated with improved OS (OR 0.80) or RFS (OR 1.04). Among patients who underwent CRS+/-HIPEC for CR-PM, the use of NAC was associated with improved OS that did not persist on multivariable analysis. However, NAC prior to CRS+/-HIPEC was a safe and feasible strategy for CR-PM, which may aid in the appropriate selection of patients for aggressive cytoreductive surgery.

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ImportanceAn initial step to reducing emergency department (ED) visits among patients with cancer is to identify the characteristics of patients visiting the ED and examine which of those visits could be prevented.ObjectiveTo explore nationwide trends and characteristics of ED visits and examine factors associated with potentially preventable ED visits and unplanned hospitalizations among patients with cancer in the US.Design, Setting, and ParticipantsThis cross-sectional study used data on ED visits from the National Hospital Ambulatory Medical Care Survey from January 1, 2012, to December 31, 2019; US Cancer Statistics reports were used to estimate new cancer cases each year. Frequencies and trends among 35 510 014 ED visits by adult patients (aged ≥18 years) with cancer were calculated.Main Outcomes and MeasuresThe primary outcome was potentially preventable ED visits, and secondary outcomes were unplanned hospitalizations and the immediacy of the ED visits. Potentially preventable ED visits were identified using the Centers for Medicare & Medicaid Services definition. The Emergency Severity Index, a triage algorithm that ranks patients based on the urgency of their health care condition, was used to measure the immediacy of ED visits (immediate [most urgent], emergent, urgent, less urgent, and nonurgent), with the categories of immediate and emergent classified as high acuity. The Wilcoxon rank sum test was used to calculate trends in ED visits among patients with cancer over time. Multivariable logistic regression analyses were performed to examine the associations of patient, hospital, and temporal factors with potentially preventable ED use and ED use resulting in hospitalization.ResultsAmong 854 911 106 ED visits, 35 510 014 (4.2%) were made by patients with cancer (mean [SD] age, 66.2 [16.2] years); of those, 55.2% of visits were among women, 73.2% were among non-Hispanic White individuals, 89.8% were among patients living in a private residence, and 54.3% were among Medicare enrollees. A total of 18 316 373 ED visits (51.6%) were identified as potentially preventable, and 5 770 571 visits (21.3%) were classified as high acuity. From 2012 to 2019, potentially preventable ED visits increased from 1 851 692 to 3 214 276. Pain (36.9%) was the most common reason for potentially preventable ED visits. The number of patients who visited an ED because of pain increased from 1 192 197 in 2012 to 2 405 849 in 2019 (a 101.8% increase). Overall, 28.9% of ED visits resulted in unplanned hospitalizations, which did not change significantly over time (from 32.2% in 2012 to 26.6% in 2019; P = .78 for trend). Factors such as residence in a nursing home (odds ratio, 1.73; 95% CI, 1.25-2.41) were positively associated with having a potentially preventable ED visit, and factors such as the presence of more than 1 comorbidity (odds ratio, 1.82; 95% CI, 1.43-2.32) were positively associated with having an unplanned hospitalization.Conclusions and RelevanceIn this study, 51.6% of ED visits among patients with cancer were identified as potentially preventable, and the absolute number of potentially preventable ED visits increased substantially between 2012 and 2019. These findings highlight the need for cancer care programs to implement evidence-based interventions to better manage cancer treatment complications, such as uncontrolled pain, in outpatient and ambulatory settings.