Contribution of the Global Regulator Gene gacA to Persistence and Dissemination of Pseudomonas fluorescens Biocontrol Strain CHA0 Introduced into Soil Microcosms

Structural and regulatory genes involved in the synthesis of antimicrobial metabolites are essential for the biocontrol activity of fluorescent pseudomonads and, in principle, amenable to genetic engineering for strain improvement. An eventual large-scale release of such bacteria raises the question of whether such genes also contribute to the persistence and dissemination of the bacteria in soil ecosystems. Pseudomonas fluorescens wild-type strain CHA0 protects plants against a variety of fungal diseases and produces several antimicrobial metabolites. The regulatory gene gacA globally controls antibiotic production and is crucial for disease suppression in CHA0. This gene also regulates the production of extracellular protease and phospholipase. The contribution of gacA to survival and vertical translocation of CHA0 in soil microcosms of increasing complexity was studied in coinoculation experiments with the wild type and a gacA mutant which lacks antibiotics and some exoenzymes. Both strains were marked with spontaneous resistance to rifampin. In a closed system with sterile soil, strain CHA0 and the gacA mutant multiplied for several weeks, whereas these strains declined exponentially in nonsterile soil of different Swiss origins. The gacA mutant was less persistent in nonrhizosphere raw soil than was the wild type, but no competitive disadvantage when colonizing the rhizosphere and roots of wheat was found in the particular soil type and during the period studied. Vertical translocation was assessed after strains had been applied to undisturbed, long (60-cm) or short (20-cm) soil columns, both planted with wheat. A smaller number of cells of the gacA mutant than of the wild type were detected in the percolated water and in different depths of the soil column. Single-strain inoculation gave similar results in all microcosms tested. We conclude that mutation in a single regulatory gene involved in antibiotic and exoenzyme synthesis can affect the survival of P. fluorescens more profoundly in unplanted soil than in the rhizosphere

The role of patient navigators in ambulatory care: overview of systematic reviews

Budde H, Williams GA, Winkelmann J, Pfirter L, Maier CB. The role of patient navigators in ambulatory care: overview of systematic reviews. BMC Health Services Research. 2021;21(1): 1166.**Background** Patient navigators have been introduced across various countries to enable timely access to healthcare services and to ensure completion of diagnosis and follow-up of care. There is an increasing evidence on the the role of patient navigation for patients and healthcare systems. The aim of this study was to analyse the evidence on patient navigation interventions in ambulatory care and to evaluate their effects on individuals and health system outcomes. **Methods** An overview of reviews was conducted, following a prespecified protocol. All patients in ambulatory care or transitional care setting were included in this review as long as it was related to the role of patient navigators. The study analysed patient navigators covering a wide range of health professionals such as physicians, nurses, pharmacists, social workers and lay health workers or community-based workers with no or very limited training. Studies including patient-related measures and health system-related outcomes were eligible for inclusion. A rigorous search was performed in multiple data bases. After reaching a high inter-rater agreement of 0.86, title and abstract screening was independently performed. Of an initial 14,248 search results and an additional 62 articles identified through the snowballing approach, a total of 7159 hits were eligible for title/abstract screening. 679  articles were included for full-text screening. **Results** Eleven systematic reviews were included covering various patient navigation intervention in cancer care, disease screening, transitional care and for various chronic conditions and multimorbidity. Nine systematic reviews primarily tailored services to ethnic minorities or other disadvantaged groups. Patient navigators performed tasks such as providing education and counselling, translations, home visits, outreach, scheduling of appointments and follow-up. Eight reviews identified positive outcomes in expanding access to care, in particular for vulnerable patient groups. Two reviews on patient navigation in transitional care reported improved patient outcomes, hospital readmission rates and mixed evidence on quality of life and emergency department visits. Two reviews demonstrated improved patient outcomes for persons with various chronic conditions and multimorbidity. **Conclusions** Patient navigators were shown to expand access to screenings and health services for vulnerable patients or population groups with chronic conditions who tend to underuse health services

Skill-Mix Changes Targeting Health Promotion and Prevention Interventions and Effects on Outcomes in all Settings (Except Hospitals): Overview of Reviews

Objectives: Skill-mix changes to step up health promotion and prevention are increasing, but there is limited evidence on their effects.Methods: Overview of reviews, based on a protocol. The search was carried out in six databases, screening was performed ensuring high interrater reliability. All countries, health professions and lay workers in all settings (except hospitals) were included, quality appraisals performed.Results: A total of 31 systematic reviews were included. Expanded roles performing outreach (e.g., home visits) had mostly positive effects on access and health outcomes, primarily for hard-to-reach groups. Task-shifting in colorectal or skin cancer screenings (performed by advanced practice nurses) were suggested effective; supporting roles (by community health workers) increased uptake in screenings, but based on limited evidence. Expanded roles of various professions focusing on lifestyle modification showed promising effects in most reviews, including weight, diet, smoking cessation and physical activity. Reviews on cost-effectiveness were based on limited evidence.Conclusion: Promising skill-mix changes included expanded roles providing lifestyle modifying interventions, task-shifting, and outreach roles for hard-to-reach groups, whereas evidence on costs was limited

Skill-Mix Changes Targeting Health Promotion and Prevention Interventions and Effects on Outcomes in all Settings (Except Hospitals): Overview of Reviews

Maier CB, Winkelmann J, Pfirter L, Williams GA. Skill-Mix Changes Targeting Health Promotion and Prevention Interventions and Effects on Outcomes in all Settings (Except Hospitals): Overview of Reviews. International Journal of Public Health. 2023;68.Objectives:Skill-mix changes to step up health promotion and prevention are increasing, but there is limited evidence on their effects.Methods:Overview of reviews, based on a protocol. The search was carried out in six databases, screening was performed ensuring high interrater reliability. All countries, health professions and lay workers in all settings (except hospitals) were included, quality appraisals performed.Results:A total of 31 systematic reviews were included. Expanded roles performing outreach (e.g., home visits) had mostly positive effects on access and health outcomes, primarily for hard-to-reach groups. Task-shifting in colorectal or skin cancer screenings (performed by advanced practice nurses) were suggested effective; supporting roles (by community health workers) increased uptake in screenings, but based on limited evidence. Expanded roles of various professions focusing on lifestyle modification showed promising effects in most reviews, including weight, diet, smoking cessation and physical activity. Reviews on cost-effectiveness were based on limited evidence.Conclusion:Promising skill-mix changes included expanded roles providing lifestyle modifying interventions, task-shifting, and outreach roles for hard-to-reach groups, whereas evidence on costs was limited

The role of patient navigators in ambulatory care: overview of systematic reviews

Background: Patient navigators have been introduced across various countries to enable timely access to healthcare services and to ensure completion of diagnosis and follow-up of care. There is an increasing evidence on the the role of patient navigation for patients and healthcare systems. The aim of this study was to analyse the evidence on patient navigation interventions in ambulatory care and to evaluate their effects on individuals and health system outcomes. Methods: An overview of reviews was conducted, following a prespecified protocol. All patients in ambulatory care or transitional care setting were included in this review as long as it was related to the role of patient navigators. The study analysed patient navigators covering a wide range of health professionals such as physicians, nurses, pharmacists, social workers and lay health workers or community-based workers with no or very limited training. Studies including patient-related measures and health system-related outcomes were eligible for inclusion. A rigorous search was performed in multiple data bases. After reaching a high inter-rater agreement of 0.86, title and abstract screening was independently performed. Of an initial 14,248 search results and an additional 62 articles identified through the snowballing approach, a total of 7159 hits were eligible for title/abstract screening. 679 articles were included for full-text screening. Results: Eleven systematic reviews were included covering various patient navigation intervention in cancer care, disease screening, transitional care and for various chronic conditions and multimorbidity. Nine systematic reviews primarily tailored services to ethnic minorities or other disadvantaged groups. Patient navigators performed tasks such as providing education and counselling, translations, home visits, outreach, scheduling of appointments and follow-up. Eight reviews identified positive outcomes in expanding access to care, in particular for vulnerable patient groups. Two reviews on patient navigation in transitional care reported improved patient outcomes, hospital readmission rates and mixed evidence on quality of life and emergency department visits. Two reviews demonstrated improved patient outcomes for persons with various chronic conditions and multimorbidity. Conclusions: Patient navigators were shown to expand access to screenings and health services for vulnerable patients or population groups with chronic conditions who tend to underuse health services