Layering vaccination with antibiotic therapy results in protection and clearance of Burkholderia pseudomallei in Balb/c mice.

Melioidosis is a disease that is difficult to treat due to the causative organism, Burkholderia pseudomallei being inherently antibiotic resistant and it having the ability to invade, survive, and replicate in an intracellular environment. Combination therapy approaches are routinely being evaluated in animal models with the aim of improving the level of protection and clearance of colonizing bacteria detected. In this study, a subunit vaccine layered with the antibiotic finafloxacin was evaluated in vivo against an inhalational infection with B. pseudomallei in Balb/c mice. Groups of mice vaccinated, infected, and euthanized at antibiotic initiation had a reduced bacterial load compared to those that had not been immunized. In addition, the subunit vaccine provided a synergistic effect when it was delivered with a CpG ODN and finafloxacin was initiated at 48 h post-challenge. Vaccination was also shown to improve the outcome, in a composite measure of survival and clearance. In summary, layering a subunit vaccine with the antibiotic finafloxacin is a promising therapeutic alternative for use in the treatment of B. pseudomallei infections.

Differences in the gut microbiota between Gurkhas and soldiers of British origin.

Previous work indicated that the incidence of travellers' diarrhoea (TD) is higher in soldiers of British origin, when compared to soldiers of Nepalese descent (Gurkhas). We hypothesise that the composition of the gut microbiota may be a contributing factor in the risk of developing TD in soldiers of British origin. This study aimed to characterise the gut microbial composition of Gurkha and non-Gurkha soldiers of the British Army. Recruitment of 38 soldiers (n = 22 Gurkhas, n = 16 non-Gurkhas) and subsequent stool collection, enabled shotgun metagenomic sequencing-based analysis of the gut microbiota. The microbiota of Gurkhas had significantly (P < 0.05) lower diversity, for both Shannon and Simpson diversity indices, using species level markers than the gut microbiota of non-Gurkha soldiers. Non-metric Multidimensional Scaling (NMDS) of the Bray-Curtis distance matrix revealed a significant difference in the composition of the gut microbiota between Gurkhas and non-Gurkha soldiers, at both the species level (P = 0.0178) and the genus level (P = 0.0483). We found three genera and eight species that were significantly enriched in the non-Gurkha group and one genus (Haemophilus) and one species (Haemophilus parainfluenzae) which were enriched in the Gurkha group. The difference in the microbiota composition between Gurkha soldiers and soldiers of British origin may contribute to higher colonization resistance against diarrhoeal pathogens in the former group. Our findings may enable further studies into interventions that modulate the gut microbiota of soldiers to prevent TD during deployment.

Phosphodiesterase 5 inhibitors (PDE5i) for the treatment of Raynaud's phenomenon.

BACKGROUND: Raynaud's phenomenon is a vasodilatory phenomenon characterised by digital pallor, cyanosis, and pain of the extremities. Primary Raynaud's phenomenon has no underlying disease associated with it, while secondary Raynaud's phenomenon is associated with connective tissue disorders such as systemic sclerosis. Systemic sclerosis causes fibrosis and commonly affects the skin and internal organs such as the gastrointestinal tract, lungs, kidney, and heart. Phosphodiesterase 5 inhibitors (PDE5i) are a class of drugs that increases blood flow to the extremities and may be beneficial in the treatment of Raynaud's phenomenon. OBJECTIVES: To assess the benefits and harms of PDE5i compared to placebo for the treatment of Raynaud's phenomenon. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, and clinical trial registries up to June 2022. We did not apply any language restrictions. We searched the bibliographies of retrieved articles and contacted key experts in the field for additional and unpublished data. SELECTION CRITERIA: Randomised controlled trials (RCTs) comparing PDE5i to placebo in people with primary and secondary Raynaud's phenomenon. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. MAIN RESULTS: This review included nine RCTs which ranged in duration from four to eight weeks and included a total of 411 participants. The majority had Raynaud's phenomenon secondary to systemic sclerosis. Tadalafil was assessed in four studies, sildenafil in three studies, vardenafil in one study, and a new PDE5 inhibitor known as "PF-00489791" in one study. Three studies were parallel design and six studies were cross-over. The frequency of attacks per week was 24 with placebo and PDE5i reduced the frequency of attacks by an average of three attacks per week (mean difference (MD) -3.07, 95% confidence interval (CI) -5.15 to -1.00; 8 studies; low-certainty evidence). The duration of attacks per day was 55 minutes with placebo and PDE5i reduced the duration of attacks by an average of five minutes (MD -5.31, 95% CI -8.90 to -1.71; 8 studies; low-certainty evidence). Very low-certainty evidence from one study with eight participants showed severity of Raynaud's attacks (assessed on a 10 cm visual analogue scale with lower scores indicating less severity) was 20% lower with a PDE5i (3.7 with placebo compared to 1.6 with treatment; MD -2.1, 95% CI -2.7 to 1.4; very low-certainty evidence). Pain and patient global assessment were assessed on a 10 cm visual analogue scale with lower scores indicating improvement. Low-certainty evidence showed that the use of PDE5i may result in little to no difference compared to placebo in reducing the average pain of Raynaud's attacks (3 to 2.9; MD -0.10, 95% CI -0.78 to 0.57; 4 studies). Global scores were 36% lower with the use of a PDE5i compared to placebo (9.2 to 5.6; MD -3.59, 95% CI -4.45 to -2.73; 1 study, 24 participants; low-certainty evidence). The rate of withdrawals during treatment with PDE5i ranged from 4% to 20% compared with 2% in the placebo group in five studies. Four studies reported no withdrawals due to adverse events. Seven studies reported no serious adverse events. The rate of serious adverse events reported in two studies ranged from 2% during treatment to 4% with placebo. The majority of the studies were judged as low or unclear risk of bias for selection, performance, and detection bias. Almost half were judged at high risk of attrition bias and unclear risk for selective reporting bias. We downgraded frequency of attacks, duration of attacks, pain intensity, and patient global assessment for small sample sizes and concerns about inconsistency and graded each as low certainty of evidence. We downgraded severity of attacks to very low certainty due to serious concerns about imprecision and publication bias. We downgraded withdrawals due to adverse events and serious adverse events to moderate certainty of evidence due to a low number of reported events. AUTHORS' CONCLUSIONS: Based on low-certainty evidence, PDE5i may reduce the frequency of attacks of Raynaud's phenomenon by a small amount per week, result in a small reduction in the duration of attack, improve patients' global assessment of their disease, and result in little to no difference in pain. PDE5i probably result in little or no difference in serious adverse events but slightly increase the likelihood of withdrawing from treatment due to an adverse event.

Slow growing bacteria survive bacteriophage in isolation.

The interactions between bacteria and bacteriophage have important roles in the global ecosystem; in turn changes in environmental parameters affect the interactions between bacteria and phage. However, there is a lack of knowledge on whether clonal bacterial populations harbour different phenotypes that respond to phage in distinct ways and whether the abundance of such phenotypes within bacterial populations is affected by variations in environmental parameters. Here we study the impact of variations in nutrient availability, bacterial growth rate and phage abundance on the interactions between the phage T4 and individual Escherichia coli cells confined in spatial refuges. Surprisingly, we found that fast growing bacteria survive together with all of their clonal kin cells, whereas slow growing bacteria survive in isolation. We also discovered that the number of bacteria that survive in isolation decreases at increasing phage doses possibly due to lysis inhibition in the presence of secondary adsorptions. We further show that these changes in the phenotypic composition of the E. coli population have important consequences on the bacterial and phage population dynamics and should therefore be considered when investigating bacteria-phage interactions in ecological, health or food production settings in structured environments.

In Vitro Activity of Finafloxacin against Panels of Respiratory Pathogens.

This study determined the in vitro activity of finafloxacin against panels of bacterial strains, representative of those associated with infection in cystic fibrosis patients and predominately isolated from clinical cases of respiratory disease. Many of these isolates were resistant to various antimicrobials evaluated including the aminoglycosides, cephalosporins, carbapenems and fluoroquinolones. Broth microdilution assays were performed at neutral and acidic pH, to determine antimicrobial activity. Finafloxacin demonstrated superior activity at reduced pH for all of the bacterial species investigated, highlighting the requirement to determine the activity of antimicrobials in host-relevant conditions.

In Vitro Activity of Novel Topoisomerase Inhibitors against Francisella tularensis and Burkholderia pseudomallei.

Antimicrobial resistance is a global issue, and the investigation of alternative therapies that are not traditional antibiotics are warranted. Novel bacterial type II topoisomerase inhibitors (NBTIs) have recently emerged as a novel class of antibiotics with reduced potential for cross-resistance to fluoroquinolones due to their novel mechanism of action. This study investigated the in vitro activity of a series of cyclohexyl-oxazolidinone bacterial topoisomerase inhibitors against type strains of Francisella tularensis and Burkholderia pseudomallei. Broth microdilution, time-kill, and cell infection assays were performed to determine activity against these biothreat pathogens. Two candidates were identified that demonstrated in vitro activity in multiple assays that in some instances was equivalent to ciprofloxacin and doxycycline. These data warrant the further evaluation of these novel NBTIs and future iterations in vitro and in vivo.

Evidence for the Efficacy of Commercially Available Wearable Biofeedback Gait Devices: Consumer-Centered Review.

BACKGROUND: The number of wearable technological devices or sensors that are commercially available for gait training is increasing. These devices can fill a gap by extending therapy outside the clinical setting. This was shown to be important during the COVID-19 pandemic when people could not access one-on-one treatment. These devices vary widely in terms of mechanisms of therapeutic effect, as well as targeted gait parameters, availability, and strength of the evidence supporting the claims. OBJECTIVE: This study aimed to create an inventory of devices targeting improvement in gait pattern and walking behavior and identify the strength of the evidence underlying the claims of effectiveness for devices that are commercially available to the public. METHODS: As there is no systematic or reproducible way to identify gait training technologies available to the public, we used a pragmatic, iterative approach using both the gray and published literature. Four approaches were used: simple words, including some suggested by laypersons; devices endorsed by condition-specific organizations or charities; impairment-specific search terms; and systematic reviews. A findable list of technological devices targeting walking was extracted separately by 3 authors. For each device identified, the evidence for efficacy was extracted from material displayed on the websites, and full-text articles were obtained from the scientific databases PubMed, Ovid MEDLINE, Scopus, or Google Scholar. Additional information on the target population, mechanism of feedback, evidence for efficacy or effectiveness, and commercial availability was obtained from the published material or websites. A level of evidence was assigned to each study involving the device using the Oxford Centre for Evidence-Based Medicine classification. We also proposed reporting guidelines for the clinical appraisal of devices targeting movement and mobility. RESULTS: The search strategy for this consumer-centered review yielded 17 biofeedback devices that claim to target gait quality improvement through various sensory feedback mechanisms. Of these 17 devices, 11 (65%) are commercially available, and 6 (35%) are at various stages of research and development. Of the 11 commercially available devices, 4 (36%) had findable evidence for efficacy potential supporting the claims. Most of these devices were targeted to people living with Parkinson disease. The reporting of key information about the devices was inconsistent; in addition, there was no summary of research findings in layperson's language. CONCLUSIONS: The amount of information that is currently available to the general public to help them make an informed choice is insufficient, and, at times, the information presented is misleading. The evidence supporting the effectiveness does not cover all aspects of technology uptake. Commercially available technologies help to provide continuity of therapy outside the clinical setting, but there is a need to demonstrate effectiveness to support claims made by the technologies.

The BALB/c Mouse Model for the Evaluation of Therapies to Treat Infections with Aerosolized Burkholderia pseudomallei.

Burkholderia pseudomallei, the causative agent of the disease melioidosis, has been isolated from the environment in 45 countries. The treatment of melioidosis is complex, requiring lengthy antibiotic regimens, which can result in the relapse of the disease following treatment cessation. It is important that novel therapies to treat infections with B. pseudomallei be assessed in appropriate animal models, and discussions regarding the different protocols used between laboratories are critical. A 'deep dive' was held in October 2020 focusing on the use of the BALB/c mouse model and the inhalational route of infection to evaluate new antibiotic therapies.

Efficacy of finafloxacin in a murine model of inhalational glanders.

Burkholderia mallei, the causative agent of glanders, is principally a disease of equines, although it can also infect humans and is categorized by the U.S. Centers for Disease Control and Prevention as a category B biological agent. Human cases of glanders are rare and thus there is limited information on treatment. It is therefore recommended that cases are treated with the same therapies as used for melioidosis, which for prophylaxis, is co-trimoxazole (trimethoprim/sulfamethoxazole) or co-amoxiclav (amoxicillin/clavulanic acid). In this study, the fluoroquinolone finafloxacin was compared to co-trimoxazole as a post-exposure prophylactic in a murine model of inhalational glanders. BALB/c mice were exposed to an aerosol of B. mallei followed by treatment with co-trimoxazole or finafloxacin initiated at 24 h post-challenge and continued for 14 days. Survival at the end of the study was 55% or 70% for mice treated with finafloxacin or co-trimoxazole, respectively, however, this difference was not significant. However, finafloxacin was more effective than co-trimoxazole in controlling bacterial load within tissues and demonstrating clearance in the liver, lung and spleen following 14 days of therapy. In summary, finafloxacin should be considered as a promising alternative treatment following exposure to B. mallei.

An Investigation into the Re-Emergence of Disease Following Cessation of Antibiotic Treatment in Balb/c Mice Infected with Inhalational Burkholderia pseudomallei.

Burkholderia pseudomallei is the causative agent of melioidosis, a multifaceted disease. A proportion of the mortality and morbidity reported as a result of infection with this organism may be due to the premature cessation of antibiotic therapy typically lasting for several months. The progression of re-emergent disease was characterised in Balb/c mice following cessation of a 14 day treatment course of co-trimoxazole or finafloxacin, delivered at a human equivalent dose. Mice were culled weekly and the infection characterised in terms of bacterial load in tissues, weight loss, clinical signs of infection, cytokine levels and immunological cell counts. Following cessation of treatment, the infection re-established in some animals. Finafloxacin prevented the re-establishment of the infection for longer than co-trimoxazole, and it is apparent based on the protection offered, the development of clinical signs of disease, bodyweight loss and bacterial load, that finafloxacin was more effective at controlling infection when compared to co-trimoxazole.

Investigation of a combination therapy approach for the treatment of melioidosis.

The efficacy of finafloxacin as a component of a layered defense treatment regimen was determined in vitro and in vivo against an infection with Burkholderia pseudomallei. Doxycycline was down-selected from a panel of antibiotics evaluated in vitro and used in combination with finafloxacin in a Balb/c mouse model of inhalational melioidosis. When treatment was initiated at 24 h post-infection with B. pseudomallei, there were no differences in the level of protection offered by finafloxacin or doxycycline (as monotherapies) when compared to the combination therapy. There was evidence for improved bacterial control in the groups treated with finafloxacin (as monotherapies or in combination with doxycycline) when compared to mice treated with doxycycline. Survival comparisons of finafloxacin and doxycycline (as monotherapies) or in combination initiated at 36 h post-infection indicated that finafloxacin was superior to doxycycline. Doxycycline was also unable to control the levels of bacteria within tissues to the extent that doxycycline and finafloxacin used in combination or finafloxacin (as a sole therapy) could. In summary, finafloxacin is a promising therapy for use in the event of exposure to B. pseudomallei.

Freedom through constraint: Young women's embodiment, space and wellbeing during lockdown.

Following the emergence of the COVID-19 pandemic and the associated lockdown restrictions in March 2020, young people were suddenly faced with a reduction and reconfiguration of the spaces in which they could 'be'. This paper explores how in this lockdown context, young women (aged 10-20) experienced their bodies and wellbeing, where traditional social connections (particularly school and physical connections) were not possible. Based on qualitative responses (n = 511) from an online, open-ended survey on wellbeing, physical activity, body image and social media usage, we explore how a reduction and reconfiguration of space, understood relationally, contributes to an individual's wellbeing. Using abductive reasoning and taking a phenomenological approach, we concentrate on the embodied experience of wellbeing and how this links to the spaces in which the body is lived. We suggest that the removal of spaces during lockdown, which on the one hand can be seen as problematic for maintaining wellbeing, also enabled many young women to experience new connections - with their bodies, family, and the environment and nature, that supplemented previous connections and fostered positive relationships and wellbeing. The removal of specific performative modes of judgement associated with the school environment was a positive influence on many young women's relationships with their own bodies and their wider construction of wellbeing, but increased use of social media spaces were found to reconstitute these performative experiences. The benefits of the specific and newly delimited freedoms associated with the forced lockdown have implications for an understanding of embodied wellbeing that is not individual, instead embedded inextricably in relations of connectedness with others in space and the nature of these intersubjective experiences.

Wellbeing in Secondary Education (WISE) Study to Improve the Mental Health and Wellbeing of Teachers: A Complex System Approach to Understanding Intervention Acceptability.

Teaching staff report poorer mental health and wellbeing than the general working population. Intervention to address this issue is imperative, as poor wellbeing is associated with burnout, presenteeism, and adverse student mental health outcomes. The Wellbeing in Secondary Education (WISE) intervention is a secondary school-based programme aimed at improving the mental health and wellbeing of teachers and students. There are three components: awareness-raising for staff; a peer support service delivered by staff trained in Mental Health First Aid (MHFA); and Schools and Colleges Mental Health First Aid (MHFA) training for teachers. A cluster randomised controlled trial with integrated process and economic evaluation was conducted with 25 secondary schools in the UK (2016-2018). The intervention was largely ineffective in improving teacher mental health and wellbeing. This paper reports process evaluation data on acceptability to help understand this outcome. It adopts a complex systems perspective, exploring how acceptability is a dynamic and contextually contingent concept. Data sources were as follows: interviews with funders (n = 3); interviews with MHFA trainers (n = 6); focus groups with peer supporters (n = 8); interviews with headteachers (n = 12); and focus groups with teachers trained in Schools and Colleges MHFA (n = 7). Results indicated that WISE intervention components were largely acceptable. Initially, the school system was responsive, as it had reached a 'tipping point' and was prepared to address teacher mental health. However, as the intervention interacted with the complexities of the school context, acceptability became more ambiguous. The intervention was seen to be largely inadequate in addressing the structural determinants of teacher mental health and wellbeing (e.g. complex student and staff needs, workload, and system culture). Future teacher mental health interventions need to focus on coupling skills training and support with whole school elements that tackle the systemic drivers of the problem.

Generation of Distinct Differentially Culturable Forms of Burkholderia following Starvation at Low Temperature.

Bacteria have developed unique mechanisms to adapt to environmental stresses and challenges of the immune system. Here, we report that Burkholderia pseudomallei, the causative agent of melioidosis, and its laboratory surrogate, Burkholderia thailandensis, utilize distinct mechanisms for surviving starvation at different incubation temperatures. At 21°C, Burkholderia are present as short rods which can rapidly reactivate and form colonies on solid media. At 4°C, Burkholderia convert into coccoid forms that cannot be cultured on solid agar but can be resuscitated in liquid media supplemented with supernatant obtained from logarithmic phase cultures of B. thailandensis, or catalase and Tween 80, thus displaying characteristics of differentially culturable bacteria (DCB). These DCB have low intensity fluorescence when stained with SYTO 9, have an intact cell membrane (propidium iodide negative), and contain 16S rRNA at levels comparable with growing cells. We also present evidence that lytic transglycosylases, a family of peptidoglycan-remodeling enzymes, are involved in the generation of coccoid forms and their resuscitation to actively growing cells. A B. pseudomallei ΔltgGCFD mutant with four ltg genes deleted did not produce coccoid forms at 4°C and could not be resuscitated in the liquid media evaluated. Our findings provide insights into the adaptation of Burkholderia to nutrient limitation and the generation of differentially culturable bacteria. IMPORTANCE Bacterial pathogens exhibit physiologically distinct forms that enable their survival in an infected host, the environment and following exposure to antimicrobial agents. B. pseudomallei causes the disease melioidosis, which has a high mortality rate and is difficult to treat with antibiotics. The bacterium is endemic to several countries and detected in high abundance in the environment. Here, we report that during starvation at low temperature, B. pseudomallei produces coccoid forms that cannot grow in standard media and which, therefore, can be challenging to detect using common tools. We provide evidence that the formation of these cocci is mediated by cell wall-specialized enzymes and lytic transglycosylases, and that resuscitation of these forms occurs following the addition of catalase and Tween 80. Our findings have important implications for the disease control and detection of B. pseudomallei, an agent of both public health and defense interest.

Using a multi-omic approach to investigate the mechanism of 12-bis-THA activity against Burkholderia thailandensis.

Burkholderia pseudomallei is the causative agent of the tropical disease, melioidosis. It is intrinsically resistant to many antimicrobials and treatment requires an onerous regimen of intravenous and orally administered drugs. Relapse of disease and high rates of mortality following treatment are common, demonstrating the need for new anti-Burkholderia agents. The cationic bola-amphiphile, 12,12'-(dodecane-1,12-diyl) bis (9-amino-1,2,3,4-tetrahydroacridinium), referred to as 12-bis-THA, is a molecule with the potential to treat Burkholderia infections. 12-bis-THA spontaneously forms cationic nanoparticles that bind anionic phospholipids in the prokaryotic membrane and are readily internalized. In this study, we examine the antimicrobial activity of 12-bis-THA against strains of Burkholderia thailandensis. As B. pseudomallei produces a polysaccharide capsule we first examined if this extra barrier influenced the activity of 12-bis-THA which is known to act on the bacterial envelope. Therefore two strains of B. thailandensis were selected for further testing, strain E264 which does not produce a capsule and strain E555 which does produce a capsule that is chemically similar to that found in B. pseudomallei. In this study no difference in the minimum inhibitory concentration (MIC) was observed when capsulated (E555) and unencapsulated (E264) strains of B. thailandensis were compared, however time-kill analysis showed that the unencapsulated strain was more susceptible to 12-bis-THA. The presence of the capsule did not affect the membrane permeation of 12-bis-THA at MIC concentrations. Proteomic and metabolomic analyses showed that 12-bis-THA causes a shift in central metabolism away from glycolysis and glyoxylate cycle, and suppressed the production of the F1 domain of ATP synthase. In summary, we provide insight into the molecular mechanisms underpinning the activity of 12-bis-THA against B. thailandensis and discuss its potential for further development.

Finafloxacin, a Novel Fluoroquinolone, Reduces the Clinical Signs of Infection and Pathology in a Mouse Model of Q Fever.

Finafloxacin is a novel fluoroquinolone with optimal antibacterial activity in low pH environments, therefore offering a therapeutic advantage over some traditional antibiotics, in treating bacterial infections associated with acidic foci. Coxiella burnetii, the causative agent of Q fever, is a bacterium which resides and replicates in acidic intracellular parasitic vacuoles. The efficacy of finafloxacin was evaluated in vivo using the A/J mouse model of inhalational Q fever and was compared to doxycycline, the standard treatment for this infection and ciprofloxacin, a comparator fluoroquinolone. Finafloxacin reduced the severity of the clinical signs of infection and weight loss associated with Q fever, but did not reduce the level of bacterial colonization in tissues compared to doxycycline or ciprofloxacin. However, histopathological analysis suggested that treatment with finafloxacin reduced tissue damage associated with C. burnetii infection. In addition, we report for the first time, the use of viable counts on axenic media to evaluate antibiotic efficacy in vivo.

An intervention to improve teacher well-being support and training to support students in UK high schools (the WISE study): A cluster randomised controlled trial.

BACKGROUND: Teachers are at heightened risk of poor mental health and well-being, which is likely to impact on the support they provide to students, and student outcomes. We conducted a cluster randomised controlled trial, to test whether an intervention to improve mental health support and training for high school teachers led to improved mental health and well-being for teachers and students, compared to usual practice. We also conducted a cost evaluation of the intervention. METHODS AND FINDINGS: The intervention comprised (i) Mental Health First Aid training for teachers to support students; (ii) a mental health awareness session; and (iii) a confidential staff peer support service. In total 25 mainstream, non-fee-paying secondary schools stratified by geographical area and free school meal entitlement were randomly allocated to intervention (n = 12) or control group (n = 13) after collection of baseline measures. We analysed data using mixed-effects repeated measures models in the intention-to-treat population, adjusted for stratification variables, sex, and years of experience. The primary outcome was teacher well-being (Warwick-Edinburgh Mental Well-being Scale). Secondary outcomes were teacher depression, absence, and presenteeism, and student well-being, mental health difficulties, attendance, and attainment. Follow-up was at months 12 (T1) and 24 (T2). We collected process data to test the logic model underpinning the intervention, to aid interpretation of the findings. A total of 1,722 teachers were included in the primary analysis. Teacher well-being did not differ between groups at T2 (intervention mean well-being score 47.5, control group mean well-being score 48.4, adjusted mean difference -0.90, 95% CI -2.07 to 0.27, p = 0.130). The only effect on secondary outcomes was higher teacher-reported absence among the intervention group at T2 (intervention group median number of days absent 0, control group median number of days absent 0, ratio of geometric means 1.04, 95% CI 1.00 to 1.09, p = 0.042). Process measures indicated little change in perceived mental health support, quality of relationships, and work-related stress. The average cost of the intervention was £9,103 per school. The study's main limitations were a lack of blinding of research participants and the self-report nature of the outcome measures. CONCLUSIONS: In this study, we observed no improvements to teacher or student mental health following the intervention, possibly due to a lack of impact on key drivers of poor mental health within the school environment. Future research should focus on structural and cultural changes to the school environment, which may be more effective at improving teacher and student mental health and well-being. TRIAL REGISTRATION: www.isrctn.com ISRCTN95909211.

Individual bacteria in structured environments rely on phenotypic resistance to phage.

Bacteriophages represent an avenue to overcome the current antibiotic resistance crisis, but evolution of genetic resistance to phages remains a concern. In vitro, bacteria evolve genetic resistance, preventing phage adsorption or degrading phage DNA. In natural environments, evolved resistance is lower possibly because the spatial heterogeneity within biofilms, microcolonies, or wall populations favours phenotypic survival to lytic phages. However, it is also possible that the persistence of genetically sensitive bacteria is due to less efficient phage amplification in natural environments, the existence of refuges where bacteria can hide, and a reduced spread of resistant genotypes. Here, we monitor the interactions between individual planktonic bacteria in isolation in ephemeral refuges and bacteriophage by tracking the survival of individual cells. We find that in these transient spatial refuges, phenotypic resistance due to reduced expression of the phage receptor is a key determinant of bacterial survival. This survival strategy is in contrast with the emergence of genetic resistance in the absence of ephemeral refuges in well-mixed environments. Predictions generated via a mathematical modelling framework to track bacterial response to phages reveal that the presence of spatial refuges leads to fundamentally different population dynamics that should be considered in order to predict and manipulate the evolutionary and ecological dynamics of bacteria-phage interactions in naturally structured environments.

Intracellular Activity of Antibiotics against Coxiella burnetii in a Model of Activated Human THP-1 Cells.

We evaluated antibiotic activity against the intracellular bacterium Coxiella burnetii using an activated THP-1 cell model of infection. At clinically relevant concentrations, the intracellular bacterial load was reduced 300-fold by levofloxacin and finafloxacin, 40-fold by doxycycline, and 4-fold by ciprofloxacin and was unaffected by azithromycin. Acidification of the culture medium reduced antibiotic activity, with the exceptions of doxycycline (no change) and finafloxacin (slight improvement). This model may be used to select antibiotics to be evaluated in vivo.

Investigations of Staphylococcal contamination on environmental surfaces of a neonatal intensive care unit of a children's hospital.

Staphylococci species are known to cause healthcare-associated infections in neonatal intensive care (NICU) unit patients. Little is known about Staphylococcal contamination of NICU environments. Swabs from 25 of 46 (54%) surfaces sampled in a NICU had viable Staphylococcal contamination, with 11% contaminated by methicillin resistant Staphylococcus aureus [MRSA]. Floors by sinks and return air ducts in the NICU were the most contaminated (67% positive), possibly serving as reservoirs for Staphylococci.