Characterization of a novel polyextremotolerant fungus, Exophiala viscosa, with insights into its melanin regulation and ecological niche.

Black yeasts are polyextremotolerant fungi that contain high amounts of melanin in their cell wall and maintain a primar yeast form. These fungi grow in xeric, nutrient depletes environments which implies that they require highly flexible metabolisms and have been suggested to contain the ability to form lichen-like mutualisms with nearby algae and bacteria. However, the exact ecological niche and interactions between these fungi and their surrounding community are not well understood. We have isolated 2 novel black yeasts from the genus Exophiala that were recovered from dryland biological soil crusts. Despite notable differences in colony and cellular morphology, both fungi appear to be members of the same species, which has been named Exophiala viscosa (i.e. E. viscosa JF 03-3 Goopy and E. viscosa JF 03-4F Slimy). A combination of whole genome sequencing, phenotypic experiments, and melanin regulation experiments have been performed on these isolates to fully characterize these fungi and help decipher their fundamental niche within the biological soil crust consortium. Our results reveal that E. viscosa is capable of utilizing a wide variety of carbon and nitrogen sources potentially derived from symbiotic microbes, can withstand many forms of abiotic stresses, and excretes melanin which can potentially provide ultraviolet resistance to the biological soil crust community. Besides the identification of a novel species within the genus Exophiala, our study also provides new insight into the regulation of melanin production in polyextremotolerant fungi.

Continuous glucose monitoring indices predict poor FEV1 recovery following cystic fibrosis pulmonary exacerbations.

BACKGROUND: Little is known about the effect of dysglycemia during cystic fibrosis pulmonary exacerbation (PEx) on recovery of FEV1 percentage predicted (ppFEV1) METHODS: Continuous glucose monitoring (CGM) was commenced at the time of admission to hospital for PEx and continued for 6 weeks. The CGM indices, percentage of time glucose greater than 7.8 mmol/L (%T>7.8) and mean glucose were evaluated as predictors of absolute ppFEV1 change following treatment of PEx. RESULTS: Of the 20 participants who completed the study 13 (65%) had cystic fibrosis related diabetes (CFRD). The mean of both CGM indices were highest during the first week of pulmonary exacerbation and continued to decline over the first 4 weeks at which point they plateaued. Using multivariate regression models, factors which were predictive of maximum attained ppFEV1 change over 6 weeks were %T>7.8, mean glucose, HbA1c and preadmission ppFEV1 change from baseline. These relationships were independent of a diagnosis of CFRD, which was not associated with ppFEV1 recovery. In a longitudinal model of ppFEV1 change at weeks 1, 2 and 6, the CGM index %T>7.8 approached significance as a predictive variable. CONCLUSIONS: Hyperglycemia during PEx in adult CF patients is associated with poorer ppFEV1 recovery. Conversely, there was no association observed between CFRD diagnosis and ppFEV1 improvement, suggesting that optimization of glycemic control in CFRD patients may positively influence recovery of lung function. Further clinical trials are required to evaluate the merits of intensive glycemic control in CFRD during PEx.

Evaluating the impact of 2006 Australasian Clinical Practice Guidelines for nutrition in children with cystic fibrosis in Australia.

OBJECTIVES: To determine the association between the implementation of the 2006 Australasian Clinical Practice Guidelines for Nutrition in Cystic Fibrosis (CF) and the nutritional status of children participating in the Australian Cystic Fibrosis Data Registry (ACFDR). METHODS: This research consisted of a quantitative study using ACFDR data and a survey of clinicians and dietitians treating children with CF. Two independent cohorts of children (2-5 years and 6-11 years) were selected from ACFDR between 1998 and 2014 (N = 2304). Generalised estimating equation model was used to assess weight, height and body mass index (BMI) z-scores for each patient before and after the implementation of the nutrition guidelines. A nationwide online survey was sent to 48 clinicians to explore the enablers and barriers to implementation of the guidelines. RESULTS: Data analysis showed significant increase (p < 0.05) in mean weight, height and BMI z-scores ranging from 0.06 to 0.18 after implementation of the guidelines in both cohorts of children. Nineteen (39%) clinicians participated in the survey. The majority of the respondents adopted the recommendations into their practice and used the guidelines as part of their professional development. Structural barriers included a lack of adequate staff resources and clinic space for consultations, inappropriate staff classification, high staff turnover and lack of mentoring support. CONCLUSION: In children participating in the ACFDR, nutritional status improved after the implementation of the 2006 guidelines. Survey results revealed enablers and barriers to guideline implementation and will inform implementation strategies for the revised Australasian nutrition guidelines for CF, released in 2017.

Comparison of the visual function index to the Snellen Visual Acuity Test in predicting older adult self-restricted driving.

OBJECTIVE: In this observational study, a modified version of the Visual Function Index (VF-14) and the Snellen Visual Acuity Test were compared in how well they correlated with self-restricted driving habits in older adults. The VF-14 was originally designed to assess vision in cataract patients; however, in this study, a modified version (mVF-14) was evaluated as a tool for predicting self-restricted driving in older drivers. METHODS: During a 3-month period, 151 drivers over the age of 65 were screened at the local senior center. In addition to the Snellen Visual Acuity Test and mVF-14, each participant was given a questionnaire about their driving habits, previously used in self-restriction studies. RESULTS: Out of 151 total participants, 134 were included and 7 nondrivers and 10 subjects who did not complete all questionnaires were excluded. One hundred one participants exhibited normal visual acuity of 20/40 or better (75%), and 110 scored over 90 on the mVF-14 (82%). Spearman's rank sum correlation coefficient was used to analyze the data and showed significant negative correlation of the mVF-14 and Snellen with self-restricted driving. Individuals with normal vision (20/40 or better on the Snellen eye test) had both high and low mVF-14 scores. CONCLUSIONS: The study shows that poor vision, as indicated by the Snellen scale and low mVF-14 scores, correlates to self-imposed driving limitations. The mVF-14 showed further distinctions of self-restriction between individuals in the same Snellen Visual Acuity category. Therefore, using the mVF-14 in addition to the Snellen Visual Acuity Test can be helpful to further differentiate visual ability within older drivers who appear to have normal vision.