Face/Off: The Interchangeable Side of Candida Albicans

Due to limited mobility, fungi, like most unicellular organisms, have evolved mechanisms to adapt to sudden chemical and/or physical variation in their environment. Candida albicans is recognized as a model organism to study eukaryotic responses to environmental changes, as this human commensal yeast but also opportunistic pathogen responds to numerous environmental cues through switching morphologies from yeast to hyphae growth. This mechanism is largely controlled by two major pathways: cAMP-PKA and MAPK, but each environmental signal is sensed by specific sensors. However, morphological switching is not the only response C. albicans exerts in response to environmental cues. Recently, fungal cell wall remodeling in response to host-derived environmental cues has been identified as a way for C. albicans to manipulate the innate immune system. The fungal cell wall is composed of a chitin skeleton linked to a network of β-glucan, which anchors proteins and mannans to the fungal cell surface. As localized on the cell surface, these molecules drive interactions with the environment and other cells, particularly with host immune cells. C. albicans is recognized by immune cells such as neutrophils and macrophages via pathogen recognition receptors (PRRs) that bind different components of the cell wall. While β-glucan and mannan are proinflammatory molecules, chitin can induce anti-inflammatory responses. Interestingly, C. albicans is able to regulate the exposure of these pathogen-associated molecular patterns (PAMPs) according to environmental cues resulting in a modulation of the host immune response. This review describes the mechanisms involved in C. albicans response to environmental changes and their effect on immune recognition

Dressed to impress: impact of environmental adaptation on the Candida albicans cell wall

Candida albicans is an opportunistic fungal pathogen of humans causing superficial mucosal infections and life-threatening systemic disease. The fungal cell wall is the first point of contact between the invading pathogen and the host innate immune system. As a result, the polysaccharides that comprise the cell wall act as pathogen associated molecular patterns, which govern the host-pathogen interaction. The cell wall is dynamic and responsive to changes in the external environment. Therefore, the host environment plays a critical role in regulating the host-pathogen interaction through modulation of the fungal cell wall. This review focuses on how environmental adaptation modulates the cell wall structure and composition, and the subsequent impact this has on the innate immune recognition of C. albicans

Where does the time go? An experimental test of what social media displaces and displaced activities’ associations with affective well-being and quality of day

Drawing from media displacement theory, this article explores which activities are displaced when individuals spend time on social media. Community and undergraduate participants (N = 135) were randomly assigned to five conditions: no change in social media use, or abstinence from social media for 1 week, 2 weeks, 3 weeks, or 4 weeks. Participants completed a daily diary measuring how they spent time each day, affective well-being, and quality of day for 28 days. The results indicate that abstinence from social media increased time spent engaged in seven activities, primarily browsing the Internet, working, childcare, and cooking/cleaning. In addition, associations among psychosocial outcomes and the displaced activities were examined. Time spent working, sleeping, and cooking/cleaning were negatively associated with affective well-being and quality of day. On days participants used social media, minutes of use were negatively associated with quality of day. The results suggest that social media primarily displaces unpleasant or neutral activities

Understanding the Role of Science-Specific Literacy Strategies in Supporting Science Teaching and Student Learning: A Case Study of Preservice Elementary Teachers in a Science Methods Course That Integrated a Disciplinary Literacy Framework

The shift to student engagement in scientific and engineering practices to learn science provides opportunities for science learning and language learning to occur in tandem. These opportunities also pose new challenges for elementary pre-service teachers (PSTs) since literacy methods courses have been presented separately from science methods courses. We integrated a disciplinary literacy framework in a science methods course to help elementary PSTs understand the synergistic connections between literacy and science teaching. The purpose of this study was to examine elementary PSTs’ understanding of the use of science-specific literacy strategies to support science teaching and learning through three points of observation. Findings from three data sources indicated that PSTs showed a developing understanding of the role of disciplinary literacy in supporting student engagement in science practices and learning disciplinary core ideas. Implications for future uses of a disciplinary literacy framework for teaching and learning science and elementary PSTs’ science preparation are presented

Exploring Student Persistence in STEM Programs: A Motivational Model

To address continually decreasing enrollment and rising attrition in post-secondary STEM degree (science, technology, engineering, and mathematics) programs, particularly for women, the present study examines the utility of motivation and emotion variables to account for persistence and achievement in science in male and female students transitioning from high school to junior college. Consistent with self-determination theory (Deci & Ryan, 2012) and achievement-goal theory (Senko, Hulleman, & Harackiewicz, 2011),structural equation modelling based on data from 1,309 students from four English-language CEGEPs showed students’ achievement goals, self-efficacy, and perceived autonomy support to impact intrinsic motivation, emotions, and achievement that, in turn, predicted persistence in the science domain

BRAIN TOPiC Study: Assessing Variability in Traumatic Brain Injury (TBI) Outcome Prognostication – Do Self-Fulfilling Prophecies Exist in TBI, Too?

OBJECTIVE: In this study, we surveyed clinicians caring for patients with moderate-severe traumatic brain injury (msTBI) to assess (1) possible variability in outcome prognostication in TBI, varying by clinicians level of training and medical specialty, (2) possible biases and self-fulfilling prophecies, and (3) whether specific ICU medical complications may influence clinicians in their outcome prognostication. BACKGROUND: Patients with msTBI commonly die from withdrawal of support, likely as a consequence of an unfavorable outcome prognosis provided to the family by the treating physician. It is unknown whether prognostication may lead to self-fulfilling prophecies, and whether the presence of intensive care unit (ICU) complications may accentuate possible provider bias. DESIGN/METHODS: We conducted an anonymous electronic survey of clinicians, including faculty members (Neurology, Neurosurgery, Trauma, Anesthesia/Critical Care), neurology house staff, ICU affiliate practitioners and neuroICU nurses at a single Level I trauma center. The survey included three TBI case vignettes and their respective ICU courses. Questions were designed to assess the utilization of known TBI prognostic models, relative importance of ICU complications for outcome prognostication and aggressiveness of care recommended by the survey participant. RESULTS: The survey response rate was 72% (106 surveys returned). In all 3 cases, the majority of participants did not recommend withdrawal of care, but did predict unfavorable 6-month outcomes. 51% of participants consider medical ICU complications as very important in TBI prognostication. Age, ICU course and head CT findings are the prognostic variables considered most important to outcomes. CONCLUSIONS: We have discovered great variability in outcome predictions made by clinicians with different levels of experience in treating msTBI. Self-fulfilling prophecies may exist in msTBI outcomes. Outcome estimates should focus not only on admission variables, but also on ICU complications in order to guide clinicians in providing prognostication

Candida albicans enhances meropenem tolerance of Pseudomonas aeruginosa in a dual-species biofilm

Background: Pseudomonas aeruginosa is an opportunistic bacterium that infects the airways of cystic fibrosis patients, surfaces of surgical and burn wounds, and indwelling medical devices. Patients are prone to secondary fungal infections, with Candida albicans being commonly co-isolated with P. aeruginosa. Both P. aeruginosa and C. albicans are able to form extensive biofilms on the surfaces ofmucosa and medical devices. Objectives: To determine whether the presence of C. albicans enhances antibiotic tolerance of P. aeruginosa in a dual-species biofilm. Methods: Single- and dual-species biofilms were established in microtitre plates and the survival of each species was measured following treatment with clinically relevant antibiotics. Scanning electron microscopy and confocal microscopy were used to visualize biofilm structure. Results: C. albicans enhances P. aeruginosa biofilm tolerance to meropenem at the clinically relevant concentration of 5 mg/L. This effect is specific to biofilm cultures and is dependent upon C. albicans extracellular matrix polysaccharides, mannan and glucan, with C. albicans cells deficient in glycosylation structures not enhancing P. aeruginosa tolerance tomeropenem. Conclusions: We propose that fungal mannan and glucan secreted into the extracellular matrix of P. aeruginosa/C. albicans dual-species biofilms play a central role in enhancing P. aeruginosa tolerance to meropenem, which has direct implications for the treatment of coinfected patients

Carbonic anhydrase inhibitors. Inhibition of the β-class enzymes from the fungal pathogens Candida albicans and Cryptococcus neoformans with branched aliphatic/aromatic carboxylates and their derivatives

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Where is “policy” in dissemination and implementation science? Recommendations to advance theories, models, and frameworks: EPIS as a case example

BackgroundImplementation science aims to accelerate the public health impact of evidence-based interventions. However, implementation science has had too little focus on the role of health policy - and its inseparable politics, polity structures, and policymakers - in the implementation and sustainment of evidence-based healthcare. Policies can serve as determinants, implementation strategies, the evidence-based "thing" to be implemented, or another variable in the causal pathway to healthcare access, quality, and patient outcomes. Research describing the roles of policy in dissemination and implementation (D&I) efforts is needed to resolve persistent knowledge gaps about policymakers' evidence use, how evidence-based policies are implemented and sustained, and methods to de-implement policies that are ineffective or cause harm. Few D&I theories, models, or frameworks (TMF) explicitly guide researchers in conceptualizing where, how, and when policy should be empirically investigated. We conducted and reflected on the results of a scoping review to identify gaps of existing Exploration, Preparation, Implementation, and Sustainment (EPIS) framework-guided policy D&I studies. We argue that rather than creating new TMF, researchers should optimize existing TMF to examine policy's role in D&I. We describe six recommendations to help researchers optimize existing D&I TMF. Recommendations are applied to EPIS, as one example for advancing TMF for policy D&I.Recommendations(1) Specify dimensions of a policy's function (policy goals, type, contexts, capital exchanged). (2) Specify dimensions of a policy's form (origin, structure, dynamism, outcomes). (3) Identify and define the nonlinear phases of policy D&I across outer and inner contexts. (4) Describe the temporal roles that stakeholders play in policy D&I over time. (5) Consider policy-relevant outer and inner context adaptations. (6) Identify and describe bridging factors necessary for policy D&I success.ConclusionResearchers should use TMF to meaningfully conceptualize policy's role in D&I efforts to accelerate the public health impact of evidence-based policies or practices and de-implement ineffective and harmful policies. Applying these six recommendations to existing D&I TMF advances existing theoretical knowledge, especially EPIS application, rather than introducing new models. Using these recommendations will sensitize researchers to help them investigate the multifaceted roles policy can play within a causal pathway leading to D&I success