Decontamination of Spores on Model Stainless-Steel Surface by Using Foams Based on Alkyl Polyglucosides.

In the food industry, the surfaces of processing equipment are considered to be major factors in the risk of food contamination. The cleaning process of solid surfaces is essential, but it requires a significant amount of water and chemicals. Herein, we report the use of foam flows based on alkyl polyglucosides (APGs) to remove spores of Bacillus subtilis on stainless-steel surfaces as the model-contaminated surface. Sodium dodecyl sulfate (SDS) was also studied as an anionic surfactant. Foams were characterized during flows by measuring the foam stability and the bubble size. The efficiency of spores' removal was assessed by enumerations. We showed that foams based on APGs could remove efficiently the spores from the surfaces, but slightly less than foams based on SDS due to an effect of SDS itself on spores removal. The destabilization of the foams at the end of the process and the recovery of surfactant solutions were also evaluated by using filtration. Following a life cycle assessment (LCA) approach, we evaluated the impact of the foam flow on the global environmental footprint of the process. We showed significant environmental impact benefits with a reduction in water and energy consumption for foam cleaning. APGs are a good choice as surfactants as they decrease further the environmental impacts.

Helping High School-Aged Military Dependents With Autism Gain Employment Through Project SEARCH + ASD Supports.

INTRODUCTION: Youth with autism spectrum disorder (ASD) face high rates of unemployment, with unique challenges for military-dependent and -connected youth with ASD. This paper reports preliminary findings from Year One of a randomized waitlist controlled trial investigating the efficacy of the Project SEARCH + ASD Supports (PS + ASD) intervention model for military-dependent and -connected youth with ASD. METHODS: Treatment group participants (n = 6) participated in internships at a military installation in the southeastern United States; waitlist group participants (n = 8) received special education transition services at their local high schools. Employment outcome data were collected at 12 months for both groups. RESULTS: Fourteen unique internship experiences were developed across seven business partner organizations on the military installation during Year One. Five of six PS + ASD treatment group participants obtained competitive integrated employment for an overall employment rate of 83.3%. Four of the positions were federal jobs. None of the waitlist group participants obtained competitive integrated employment during the same period. CONCLUSIONS: Initial results are promising and suggest that the PS + ASD model may help to meet the transition needs of military-dependent and -connected youth with ASD and the employment needs of local military communities.

Return to Work Interventions for Cancer Survivors: A Systematic Review and a Methodological Critique.

Cancer patients are more at risk of being unemployed or having difficulties to return to work (RTW) compared to individuals without health concerns, and is thus a major public health issue. The aim of this systematic review is to identify and describe the interventions developed specifically to help cancer patients to RTW after treatment. Two researchers independently screened the articles for inclusion and Critical Appraisal Skills Program (CASP) checklists were used to assess the methodology of the included studies. Ten manuscripts met the inclusion criteria. The type of studies were three quasi-experimental studies, three longitudinal studies, three randomized controlled trials (RCTs) and a qualitative study. RTW interventions were conducted in or outside the hospital (n = 6 and 3 respectively), or both (n = 1). Improvements in RTW were only observed in quasi-experimental studies. No improvement in RTW was noted in RCTs, nor in other measures (e.g., quality of life, fatigue). Lack of statistically significant improvement does not necessarily reflect reality, but may be attributed to non-adapted research methods. This systematic review underscores the need for researches in the RTW field to reach a consensus on RTW criteria and their assessment. Recommendations to this effect are suggested.

Role of the global regulator Rex in control of NAD+ -regeneration in Clostridioides (Clostridium) difficile.

For the human pathogen Clostridioides (also known as Clostridium) difficile, the ability to adapt to nutrient availability is critical for its proliferation and production of toxins during infection. Synthesis of the toxins is regulated by the availability of certain carbon sources, fermentation products and amino acids (e.g. proline, cysteine, isoleucine, leucine and valine). The effect of proline is attributable at least in part to its role as an inducer and substrate of D-proline reductase (PR), a Stickland reaction that regenerates NAD+ from NADH. Many Clostridium spp. use Stickland metabolism (co-fermentation of pairs of amino acids) to generate ATP and NAD+ . Synthesis of PR is activated by PrdR, a proline-responsive regulatory protein. Here we report that PrdR, in the presence of proline, represses other NAD+ -generating pathways, such as the glycine reductase and succinate-acetyl CoA utilization pathways leading to butyrate production, but does so indirectly by affecting the activity of Rex, a global redox-sensing regulator that responds to the NAD+ /NADH ratio. Our results indicate that PR activity is the favored mechanism for NAD+ regeneration and that both Rex and PrdR influence toxin production. Using the hamster model of C. difficile infection, we revealed the importance of PrdR-regulated Stickland metabolism in the virulence of C. difficile.

Control of Clostridium difficile Physiopathology in Response to Cysteine Availability.

The pathogenicity of Clostridium difficile is linked to its ability to produce two toxins: TcdA and TcdB. The level of toxin synthesis is influenced by environmental signals, such as phosphotransferase system (PTS) sugars, biotin, and amino acids, especially cysteine. To understand the molecular mechanisms of cysteine-dependent repression of toxin production, we reconstructed the sulfur metabolism pathways of C. difficile strain 630 in silico and validated some of them by testing C. difficile growth in the presence of various sulfur sources. High levels of sulfide and pyruvate were produced in the presence of 10 mM cysteine, indicating that cysteine is actively catabolized by cysteine desulfhydrases. Using a transcriptomic approach, we analyzed cysteine-dependent control of gene expression and showed that cysteine modulates the expression of genes involved in cysteine metabolism, amino acid biosynthesis, fermentation, energy metabolism, iron acquisition, and the stress response. Additionally, a sigma factor (SigL) and global regulators (CcpA, CodY, and Fur) were tested to elucidate their roles in the cysteine-dependent regulation of toxin production. Among these regulators, only sigL inactivation resulted in the derepression of toxin gene expression in the presence of cysteine. Interestingly, the sigL mutant produced less pyruvate and H2S than the wild-type strain. Unlike cysteine, the addition of 10 mM pyruvate to the medium for a short time during the growth of the wild-type and sigL mutant strains reduced expression of the toxin genes, indicating that cysteine-dependent repression of toxin production is mainly due to the accumulation of cysteine by-products during growth. Finally, we showed that the effect of pyruvate on toxin gene expression is mediated at least in part by the two-component system CD2602-CD2601.