Infections of Fusarium spp. and Exophiala spp. are often chronic, recalcitrant, resulting in significant morbidity, causing discomfort, disfigurement, social isolation. Systemic disseminations happen in compromised patients, which are often refractory to available antifungal therapies and thereby lead to death. The antimicrobial photodynamic therapy (aPDT) has been demonstrated to effectively inactivate multiple pathogenic fungi and is considered as a promising alternative treatment for mycoses. In the present study, we applied methylene blue (8, 16, and 32 μg/ml) as a photosensitizing agent and light emitting diode (635 ± 10 nm, 12 and 24 J/cm2), and evaluated the effects of photodynamic inactivation on five strains of Fusarium spp. and five strains of Exophiala spp., as well as photodynamic effects on in vitro susceptibility to itraconazole, voriconazole, posaconazole and amphotericin B, both planktonic and biofilm forms. Photodynamic therapy was efficient in reducing the growth of all strains tested, exhibiting colony forming unit-reductions of up to 6.4 log10 and 5.6 log10 against planktonic cultures and biofilms, respectively. However, biofilms were less sensitive since the irradiation time was twice longer than that of planktonic cultures. Notably, the photodynamic effects against Fusarium strains with high minimal inhibitory concentration (MIC) values of ≥16, 4-8, 4-8, and 2-4 μg/ml for itraconazole, voriconazole, posaconazole and amphotericin B, respectively, were comparable or even superior to Exophiala spp., despite Exophiala spp. showed relatively better antifungal susceptibility profile. MIC ranges against planktonic cells of both species were up to 64 times lower after aPDT treatment. Biofilms of both species showed high sessile MIC50 (SMIC50) and SMIC80 of ≥16 μg/ml for all azoles tested and variable susceptibilities to amphotericin B, with SMIC ranging between 1 and 16 μg/ml. Biofilms subjected to aPDT exhibited a distinct reduction in SMIC50 and SMIC80 compared to untreated groups for both species, except SMIC80 of itraconazole against Fusarium biofilms. In conclusion, in vitro photodynamic therapy was efficient in inactivation of Fusarium spp. and Exophiala spp., both planktonic cultures and biofilms. In addition, the combination of aPDT and antifungal drugs represents an attractive alternative to the current antifungal strategies. However, further investigations are warranted for the reliable and safe application in clinical practice.

The aim of the present study was to investigate the executive function and planning features of students with different types of learning difficulties. Students with mathematics difficulty (MD; n = 17), reading difficulty (RD; n = 12), their commonalities (MDRD; n = 22), and their typically academically developing peers (TD; n = 22) were evaluated on an array of cognitive measures (working memory, inhibition, and planning) individually. Results revealed significant differences among groups on various cognitive measures. Students in the MD, RD, and MDRD groups showed poorer performance compared to the TD group on all of the working memory, inhibition, and planning tasks. The MDRD group showed an overall weakness when comparing to other groups, indicating severe cognitive deficits in students with MDRD. The RD group showed deficits in inhibition and planning on tasks requiring verbal skills; MD students showed deficits in inhibition and planning on digit-related tasks. However, no salient difference was found between the MD, RD, and TD group on working memory. Results have implications for understanding the cognitive features of MD, RD, and MDRD, and intervention programs targeting inhibition and planning may be beneficial for improving reading and mathematics achievement in students with learning difficulties.

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The authors thank principal Yuan and his colleagues from QuYang No. 4 primary school for their helpful assistance in the process of data collection.