Multi-species biofilms of environmental microbiota isolated from fruit packing facilities promoted tolerance of Listeria monocytogenes to benzalkonium chloride.

Listeria monocytogenes may survive and persist in food processing environments due to formation of complex multi-species biofilms of environmental microbiota that co-exists in these environments. This study aimed to determine the effect of selected environmental microbiota on biofilm formation and tolerance of L. monocytogenes to benzalkonium chloride in formed biofilms. The studied microbiota included bacterial families previously shown to co-occur with L. monocytogenes in tree fruit packing facilities, including Pseudomonadaceae, Xanthomonadaceae, Microbacteriaceae, and Flavobacteriaceae. Biofilm formation ability and the effect of formed biofilms on the tolerance of L. monocytogenes to benzalkonium chloride was measured in single- and multi-family assemblages. Biofilms were grown statically on polystyrene pegs submerged in a R2A broth. Biofilm formation was quantified using a crystal violet assay, spread-plating, confocal laser scanning microscopy, and its composition was assessed using amplicon sequencing. The concentration of L. monocytogenes in biofilms was determined using the most probable number method. Biofilms were exposed to the sanitizer benzalkonium chloride, and the death kinetics of L. monocytogenes were quantified using a most probable number method. A total of 8, 8, 6, and 3 strains of Pseudomonadaceae, Xanthomonadaceae, Microbacteriaceae, and Flavobacteriaceae, respectively, were isolated from the environmental microbiota of tree fruit packing facilities and were used in this study. Biofilms formed by Pseudomonadaceae, Xanthomonadaceae, and all multi-family assemblages had significantly higher concentration of bacteria, as well as L. monocytogenes, compared to biofilms formed by L. monocytogenes alone. Furthermore, multi-family assemblage biofilms increased the tolerance of L. monocytogenes to benzalkonium chloride compared to L. monocytogenes mono-species biofilms and planktonic multi-family assemblages. These findings suggest that L. monocytogenes control strategies should focus not only on assessing the efficacy of sanitizers against L. monocytogenes, but also against biofilm-forming microorganisms that reside in the food processing built environment, such as Pseudomonadaceae or Xanthomonadaceae.

Assessing the prevalence and correlates of prenatal cannabis consumption in an urban Canadian population: a cross-sectional survey.

BACKGROUND: Recreational cannabis use was legalized in Canada in October 2018. We aimed to determine the prevalence and correlates of cannabis consumption among pregnant individuals in a single Canadian city following national legalization. METHODS: Over the period May to October 2019, we distributed an anonymous cross-sectional survey to pregnant patients attending family practice, midwifery, and low-risk and high-risk obstetrics clinics in Hamilton, Ontario. Eligibility was based on English literacy and current pregnancy. The survey included questions regarding lifetime and in-pregnancy cannabis use, intent for postpartum use and patterns of use. We also collected demographic information. We calculated descriptive statistics and performed logistic regression analyses to explore the relations between cannabis consumption and demographic characteristics. RESULTS: Of 531 pregnant individuals approached, 478 agreed and were able to participate, for a 90% participation rate. Among these 478 respondents, 54 (11%) reported consuming cannabis at some point during the pregnancy and 20 (4%) reported currently consuming cannabis. Among the 460 respondents who intended to breastfeed, 23 (5%) planned to consume cannabis during the postpartum period. Of 20 current users, 13 (65%) reported consuming cannabis at least weekly and 19 (95%) reported nausea, sleep problems or anxiety as reasons for use. Respondents without postsecondary education had 10.0-fold (95% confidence interval [CI] 4.6-23.5) greater odds of prenatal cannabis consumption than university-educated respondents. In addition, respondents who reported that their partners used cannabis had 3.9-fold (95% CI 2.2-7.3) greater odds of prenatal cannabis consumption than those who reported that their partners did not use cannabis. INTERPRETATION: Lower educational attainment and partners' cannabis consumption were associated with greater odds of inpregnancy cannabis use. These results may help to inform early intervention strategies to decrease cannabis consumption during this vulnerable period of fetal and neonatal development.

Comparison of Regularly Scheduled Ibuprofen Versus "Pro Re Nata" for Ankle Sprains in Children Treated in the Emergency Department: A Randomized Controlled Trial.

OBJECTIVE: We compared pain and degree of disability in patients with acute ankle sprains receiving regular scheduled ibuprofen versus pro re nata (PRN). METHODS: This study is a randomized single-blinded controlled trial of children aged 7 to 17 years presenting with acute ankle sprain to an emergency department. Patients were randomized to receive 10 mg/kg of ibuprofen per dose (maximum 600 mg) every 6 hours regular scheduled versus PRN. Outcome measures included a 100-mm visual analog scale pain and degree of disability at day 4. A sample size of 72 children had a power of 80% to detect a clinically meaningful difference of 20 mm between the regular and PRN group. RESULTS: We randomly assigned 99 patients to receive regular scheduled (n = 50) or PRN (n = 49) ibuprofen. Pain scores and degree of disability at day 4 showed no significant differences between groups. The rate of reported adverse effects was higher in the regular scheduled group (11.4% vs 9.5%) versus the PRN group. CONCLUSIONS: Our study suggests that there is little benefit from routinely using a regular scheduled ibuprofen regimen for acute pediatric ankle sprains.

Pregnant Canadians' Perceptions About the Transmission of Cannabis in Pregnancy and While Breastfeeding and the Impact of Information From Health Care Providers on Discontinuation of Use.

OBJECTIVE: Rates of cannabis use during pregnancy and while breastfeeding are increasing in Canada. Some observational studies have found associations between cannabis use in pregnancy and low birthweight, preterm labour, and admission to the intensive care unit. This study aimed to evaluate women's perceptions about transmission of cannabis to the fetus, and whether receiving information from a health care provider influenced their decision to stop using cannabis during pregnancy. METHODS: Pregnant women presenting to obstetrical, midwifery, and family practice clinics in the greater Hamilton, Ontario area were asked to complete an anonymous survey. Chi-square tests were used to investigate whether patient knowledge was influenced by health care providers or by self-directed learning and if this information influenced their decision to discontinue cannabis use. RESULTS: Of the 478 women surveyed, the vast majority perceived that cannabis is transmitted to the fetus during pregnancy and to the infant while breastfeeding (94.3% and 91.2%, respectively). The majority of women (99%) indicated that the advent of cannabis legalization did not influence their choice to use cannabis in pregnancy. Women who continued to use cannabis during pregnancy were more likely to report receiving information on cannabis from a health care provider (52%) than those who chose to discontinue use in pregnancy (35%) (P = 0.035). CONCLUSIONS: In our study, the proportion of pregnant women who understood that cannabis could be transmitted to the fetus in utero and to the infant via breastmilk was high. Despite this, 4.2% of women reported that they continued to use cannabis in pregnancy. More work is needed to understand why some women continue to use cannabis in pregnancy despite being informed of its risks.

Carbon Nanomaterials Alter Global Gene Expression Profiles.

Carbon nanomaterials (CNMs), which include carbon nanotubes (CNTs) and their derivatives, have diverse technological and biomedical applications. The potential toxicity of CNMs to cells and tissues has become an important emerging question in nanotechnology. To assess the toxicity of CNTs and fullerenol C60(OH)24, we in the present work used the budding yeast Saccharomyces cerevisiae, one of the simplest eukaryotic organisms that share fundamental aspects of eukaryotic cell biology. We found that treatment with CNMs, regardless of their physical shape, negatively affected the growth rates, end-point cell densities and doubling times of CNM-exposed yeast cells when compared to unexposed cells. To investigate potential mechanisms behind the CNMs-induced growth defects, we performed RNA-Seq dependent transcriptional analysis and constructed global gene expression profiles of fullerenol C60(OH)24- and CNT-treated cells. When compared to non-treated control cells, CNM-treated cells displayed differential expression of genes whose functions are implicated in membrane transporters and stress response, although differentially expressed genes were not consistent between CNT- and fullerenol C60(OH)24-treated groups, leading to our conclusion that CNMs could serve as environmental toxic factors to eukaryotic cells.

TORC2 and eisosomes are spatially interdependent, requiring optimal level of phosphatidylinositol 4, 5-bisphosphate for their integrity.

The elucidation of the organization and maintenance of the plasma membrane has been sought due to its numerous roles in cellular function. In the budding yeast Saccharomyces cerevisiae, a novel paradigm has begun to emerge in the understanding of the distribution of plasma membrane microdomains and how they are regulated. We aimed to investigate the dynamic interdependence between the protein complexes eisosome and TORC2, representing microdomains MCC and MCT, respectively. In this study, we reveal that the eisosome organizer Pil1 colocalizes with the MCT marker Avo2. Furthermore, we provide evidence that the formation of MCT is dependent on both eisosome integrity and adequate levels of the plasma membrane phosphoinositide PI(4,5)P2. Taken together, our findings indicate that TORC2, eisosomes, and PI(4,5)P2 exist in an interconnected relationship, which supports the emerging model of the plasma membrane.

Insight into Tor2, a budding yeast microdomain protein.

The plasma membrane of eukaryotic organisms is compartmentalized into microdomains. The budding yeast Saccharomyces cerevisiae presents three laterally distinct microdomains: membrane compartment containing Can1 (MCC), membrane compartment containing Pma1 (MCP), and membrane compartment containing Tor2 (MCT). Tor2 and its corresponding protein complex, target of rapamycin complex 2 (TORC2), has been of particular interest in recent years. Tor2, the main organizer of TORC2, is a highly conserved kinase that has proved to be an important regulator of multiple cellular functions including cell growth, actin polymerization, endocytosis, and sphingolipid synthesis. Despite significant advancements, the full understanding of the Tor2 signaling networks is incomplete. Here we review the most compelling evidences for the function and physiological significance of Tor2, as well as discuss possible implications and explanations for observed phenomena.