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Purpose: To report a rare case of fungal keratitis caused by Cryptococcus neoformans, highlighting its unique morphological features using in vivo confocal microscopy (IVCM). Methods: This was a retrospective case report. A 66-year-old man presented with foreign body sensation and blurred vision in his left eye for over 10 months. Results: His best-corrected visual acuity was 20/20. Slit-lamp examination revealed a gray-white lesion approximately 4–5 mm in the superficial layer of the central cornea without epithelial defects. The IVCM images revealed numerous round or round-like pathogens, each with a central highly reflective body surrounded by a dark ring, ranging in size from 5 to 30 µm, and to a maximum of 85 µm, observed in the corneal epithelium and superficial stroma. No obvious inflammatory cell infiltration was observed in the lesions or endothelium. C. neoformans infection was confirmed. The round pathogens completely disappeared after 8 weeks of treatment with topical amphotericin B and voriconazole eye drops. Conclusion: Fungal keratitis caused by C. neoformans is rare and easily overlooked due to atypical clinical signs and symptoms. This case reports the unique morphological features of C. neoformans in the cornea using IVCM for the first time, facilitating rapid, noninvasive auxiliary diagnosis of C. neoformans keratitis and treatment follow-up. [ABSTRACT FROM AUTHOR]

Some fungi have demonstrated the ability to adapt rapidly to changing environments by exhibiting morphological plasticity, a trait influenced by species and environmental factors. Here, an anamorphic yeast strain IOJ-3 exhibited unique sectorization characteristics, naturally producing diverse filamentous sectors when cultivated on potato dextrose agar (PDA) medium or natural culture medium for durations exceeding 13 days. The strain IOJ-3 and its filamentous sectors were identified as Dothiora sorbi. The morphology of the sectors was consistent and heritable. The life cycle of strain IOJ-3 was investigated through microscopic observation, emphasizing the development of conidiogenous cells as a crucial stage, from which filamentous sectors originate. Some physiological characteristics of IOJ-3 and filamentous sectors are compared, and strain IOJ-3 has a higher antibiotic tolerance than two filamentous sectors, IOJ-3a expands faster on the culture medium, and IOJ-3b can penetrate cellophane. A transcriptomic analysis was conducted to investigate the differentially expressed genes between the yeast form IOJ-3 and its two filamentous sectors, revealing a total of 594 genes that exhibited consistent differential expression relative to IOJ-3, including 44 silencing genes in IOJ-3 that were activated. Gene Ontology analysis indicated that these differentially expressed genes were primarily associated with the cellular component category. Furthermore, adding 5-Azacytidine accelerated filamentous sectorization and increased the proportion of filamentous cells of strain IOJ-3 in PD liquid media, suggesting that the filamentous sectorization observed in strain IOJ-3 is linked to processes of DNA demethylation. In conclusion, this study sheds light on the biological characteristics of D. sorbi regarding morphological transitions and provides substantial direction for exploring genes related to fungal filamentous development. [ABSTRACT FROM AUTHOR]

Candida spp. is an opportunistic pathogen capable of causing superficial to invasive infections. Morphological transition is one of the main virulence factors of this genus and, therefore, is an important variable to be considered in pharmacological interventions. Riparins I, II, III, and IV are alkamide‐type alkaloids extracted from the unripe fruit of Aniba riparia, whose remarkable pharmacological properties were previously demonstrated. This work aimed to evaluate in silico and in vitro the inhibitory effects of Riparins on the morphological transition of Candida albicans, Candida tropicalis, and Candida krusei. Molecular docking was applied to analyze the inhibitory effects of riparins against proteins such as N‐acetylglucosamine, CYP‐51, and protein kinase A (PKA) using the Ramachandran plot. The ligands were prepared by MarvinSketch and Spartan software version 14.0, and MolDock Score and Rerank Score were used to analyze the affinity of the compounds. In vitro analyses were performed by culturing the strains in humid chambers in the presence of riparins or fluconazole (FCZ). The morphology was observed through optical microscopy, and the size of the hyphae was determined using the ToupView software. In silico analysis demonstrated that all riparins are likely to interact with the molecular targets: GlcNAc (>50%), PKA (>60%), and CYP‐51 (>70%). Accordingly, in vitro analysis showed that these compounds significantly inhibited the morphological transition of all Candida strains. In conclusion, this study demonstrated that riparins inhibit Candida morphological transition and, therefore, can be used to overcome the pathogenicity of this genus. [ABSTRACT FROM AUTHOR]

Candida albicans (C. albicans) produces farnesol as a quorum sensing molecule that suppresses its filamentation. In this study, we synthesized farnesol‐imprinted nanospheres (FINs) to investigate their impact on the morphogenic transition of C. albicans, a fungus known for its pathogenicity in superficial and systemic candidiasis. FINs, synthesized for this purpose, exhibited a significantly higher binding capacity for farnesol compared to control polymers, with a 6.5‐fold increase observed. These polymers displayed a spherical morphology with diameters ranging from 500–700 nm. Treatment with FINs resulting in an increase in hyphae formation in C. albicans, indicating effective capture farnesol by the FINs. This increase in hyphae formation corresponded to a suppressed yeast form of the fungus. Consequently, FINs hold promise as a potential compound to mitigate the severity of disseminated candidiasis by depleting yeast forms. Interestingly, pre‐incubated of FINs with 0.1 mM of farnesol led to a reduction in C. albicans filamentation. This finding suggests that FINs have the capability to adsorb and release farnesol. Therefore, FINs could serve as a delivery agent for farnesol, offering protection against C. albicans filamentation. Overall, the synthesis of FINs presents a promising approach to combating C. albicans infection, whether by reducing disseminated candidiasis or preventing fungal superficial localization. [ABSTRACT FROM AUTHOR]

Polarized growth plays a key role in all domains of their biology, including morphogenesis and pathogenicity of filamentous fungi. However, little information is available about the determinants of polarized growth. The fungal Mep2, Pes1, and Cph1 proteins were identified to be involved in the dimorphic transition between yeast and hyphal forms in Candida albicans. In this study, evidence that the dimorphic fungal entomopathogen Ophiocordyceps sinensis Mep2, Pes1, and Cph1 proteins are involved in polarized growth is presented. OsMep2 was significantly upregulated at aerial hyphae and conidia germination stages. OsCph1 was significantly upregulated at aerial hyphae, conidia initiation, and conidia germination stages, and OsPes1 was significantly upregulated at the conidia germination stage. Deletions of OsMep2 , OsCph1 , and OsPes1 provoked defects in the polarized growth. The abilities of hyphal formation and the yields of blastospores and conidia for the ∆  OsMep2 , ∆ OsCph1 , and ∆  OsPes1 mutants were significantly reduced. The conidia yields of the Δ OsMep2 , Δ OsCph1 , and Δ OsPes1 mutants were decreased by 69.17%, 60.90%, and 75.82%, respectively. Moreover, the pathogenicity of the ∆  OsMep2 , ∆ OsCph1 , and ∆  OsPes1 mutants against Thitarodes xiaojinensis was significantly reduced. The mummification rate caused by wide type and Δ OsMep2 , Δ OsCph1 , and Δ OsPes1 mutants were 36.98% ± 8.52%, 0.31% ± 0.63%, 1.15% ± 1.57%, and 19.69% ± 5.6%, respectively. These results indicated that OsMep2 , OsCph1 , and OsPes1 are involved in the regulation of hyphal formation, sporulation, and pathogenicity of O. sinensis. This study provided a basis for the understanding of the fungal dimorphic development and improving the efficiency of artificial cultivation of O. sinensis. [ABSTRACT FROM AUTHOR]

A phase‐separated template prepared from a mixed monolayer of fluorinated long‐chain s‐triazine derivatives and comb copolymers containing s‐triazine rings was morphologically controlled by DNA adsorption. The adsorbed morphology of DNA was formed through a morphological transition process at the air/water interface rather than by maintaining the shape of the phase‐separated template. Dot‐like domains, circular domains, centrally protruding domains, network morphologies, and even co‐continuous surface morphologies of DNA were obtained. The phase‐separated monolayer used as a template depends on the mixed ratio of the fluorocarbon and hydrocarbon copolymer components, the copolymerization ratio of the hydrocarbon copolymers, and the chain length of the fluorinated long‐chain s‐triazine derivative, and various morphological transitions occur. The DNA introduced into the sub‐phase was selectively adsorbed onto the s‐triazine ring‐containing comb copolymer, and the adsorbed DNA assembly exhibited a morphological transition based on concerted interactions. Furthermore, by utilizing a fluorescent probe molecule, evidence of DNA morphogenesis itself was supported by its emission/quenching behavior. Highlights: Morphological control of the DNA assembly was attained.Immobilization of DNA assemblies on phase‐separated templates was achieved.Preparation of patterned templates was realized by copolymers a fluorinated derivative.Adsorption of DNA to the diamino‐s‐triazine ring was achieved by hydrogen bonding.A rearrangement of the DNA assemblies on the template was achieved. [ABSTRACT FROM AUTHOR]

Discrete polymers offer an excellent platform for comprehending the interplay between precise chain structures, distinctive self‐assembly behavior, and functional applications, whereas the development of discrete polymers with self‐immolative properties remains scarce. Here, we modularly synthesize a library of discrete self‐immolative oligourethanes containing N‐naphthylcarbamate or N‐(3‐fluorophenyl)carbamate repeating units via iterative stepwise growth. These oligourethanes undergo not only cascade 1,6‐elimination depolymerizations via photo‐mediated removal of o‐nitrobenzyl carbamate triggers but also selective cleavage of benzyl‐O linkages under MS/MS conditions even without UV light irradiation. In aqueous media, these discrete oligourethanes self‐assemble into different morphologies such as flat nanosheets, nanofibers, and nanoribbons, depending on the chain lengths and backbone compositions, and further morphological transitions are observed upon thermal annealing. [ABSTRACT FROM AUTHOR]

Candida albicans is an opportunistic polymorphic yeast that can cause life threatening systemic infections in immunocompromised individuals. It resides as commensal organism on the skin, in the gastrointestinal tracts and in the genitourinary tracts of mammalian hosts. One key attribute of C. albicans that enhances its pathogenicity is its ability to switch morphologies between unicellular yeast cells and filamentous forms, in response to diverse stimuli. C. albicansproduces farnesol as an extracellular autoregulatory compound and when farnesol accumulates above a threshold level, it inhibits yeast-to-hyphal switch as well as biofilm formation. It was shown that expression of the gene, TUP1 was slightly increased in response to farnesol, particularly at the transcriptional level and strains lacking the gene, did not respond to farnesol. To study the translational effect of farnesol on TUP1, a quantitative reverse transcriptase PCR (qRT-PCR) analysis was used to investigate the effect of farnesol on TUP1 mRNA across the polysome using RNA samples from input and polysome fractions of farnesol treated cells and cells not exposed to farnesol. The qRT-PCR data showed redistribution of the mRNA from the polysomal region to the sub-polysomal region following treatment with 100μM farnesol indicating an inhibition of the translation.

A criterion to explain the morphological growth transition from faceted to non-faceted (f-nf) morphology in the case of directional solidification is presented for pure materials. The criterion is based on the number of atomic layers at the solid–liquid interface and allows a foreknowledge of the solidification growth velocity at which f-nf transition becomes significant. The basis for the transition criterion hinges on the Cahn theory of interface structure and the theory of liquid–solid transition by the maximum entropy production rate (MEPR) principle. The criterion is tested with a number of pure materials and compared with experimental measurements for salol. The criterion fits quite well with available experimental data.

Candida albicans (C. albicans) is the most common causative agent of invasive fungal infections in hospitals. The body defends against and eliminates C. albicans infection by various mechanisms of immune response, and the latter mechanism of immune evasion is a major challenge in the clinical management of C. albicans infection. The role of macrophages in combating C. albicans infection has only recently been recognized, but the mechanisms remain to be elucidated. This review focuses on the interaction between C. albicans and macrophages (macrophages), which causes the body to generate an immune response or C. albicans immune escape, and then regulates the body's immune microenvironment, to explore the effect of C. albicans virulence resistance vs. macrophage killing and clarify the role and mechanism of C. albicans pathogenesis. In general, a thorough understanding of the molecular principles driving antifungal drug resistance is essential for the development of innovative treatments that can counteract both existing and emerging fungal threats. [ABSTRACT FROM AUTHOR]

Kinetic co‐assembly pathway induced chirality inversion along with morphology transition is of importance to understand biological processes, but still remains a challenge to realize in artificial systems. Herein, helical nanofibers consisting of phenylalanine‐based enantiomers (L/DPF) successfully transform into kinetically trapped architectures with opposite helicity through a kinetic co‐assembly pathway. By contrast, the co‐assemblies obtained by a thermodynamic pathway exhibit non‐helical structures. The formation sequence of non‐covalent interactions plays a crucial role in structural chirality of co‐assemblies. For the kinetic pathway, the hydrogen bonding between D/LPF and naphthylamide derivatives forms before π‐π stacking to facilitate the formation of helical structures with inverse handedness. This study may provide an approach to explore chirality inversion accompanied by morphology transition by manipulating the kinetic co‐assembly pathway. [ABSTRACT FROM AUTHOR]

Kickxellomycotina encompasses two fungal groups: a saprobic group in excrement and soil and an arthropod gut-inhabiting group. The evolutionary transition between these two lifestyles is unclear due to the lack of knowledge on intermediate forms and lifestyles. Here, we describe a new species, Unguispora rhaphidophoridarum, that was isolated from the excrement of cave crickets (Rhaphidophoridae) in Japan. This species has a novel lifestyle that is intermediate between the saprobic and gut-inhabiting groups. The new genus Unguispora is a member of the Kickxellales and characterized by the sterile appendages born on the sporocladium and by the claw-like ornamentation of the sporangiole. Phylogenetic analysis based on 18S and 28S nuclear ribosomal DNA showed that this fungus is distinct from all known kickxellalean genera and is sister to Linderina. The sporangiospore of the new species germinated only in anaerobiosis and grew in a yeast-like form. The yeast-like cells, defined as "secondary spores," germinated into hyphae in aerobiosis. In the alimentary tract of cave crickets, the sporangiola are attached to the proventriculus (foregut) by the claw-like ornamentation and multiplicate in the same yeast-like form as under culture. We introduce a new term, "amphibious fungi," to describe fungi that have two life stages, one outside and the other inside the host gut, like U. rhaphidophoridarum. The discovery of an amphibious fungus in Kickxellales, which was formerly considered to be only saprobic, suggests that Kickxellomycotina has evolved in association with the animal gut. [ABSTRACT FROM AUTHOR]

The ubiquitous commensal Candida albicans, part of the human microbiota, is an opportunistic pathogen able to cause a wide range of diseases, from cutaneous mycoses to life-threatening infections in immunocompromised patients. Candida albicans adapts to different environments and survives long-time starvation. The ability to switch from yeast to hyphal morphology under specific environmental conditions is associated with its virulence. Using hydrogen nuclear magnetic resonance spectroscopy, we profiled the intracellular and extracellular metabolome of C. albicans kept in water, yeast extract–peptone–dextrose (YPD), and M199 media, at selected temperatures. Experiments were carried out in hypoxia to mimic a condition present in most colonized niches and fungal infection sites. Comparison of the intracellular metabolites measured in YPD and M199 at 37 °C highlighted differences in specific metabolic pathways: (i) alanine, aspartate, glutamate metabolism, (ii) arginine and proline metabolism, (iii) glycerolipid metabolism, attributable to the diverse composition of the media. Moreover, we hypothesized that the subtle differences in the M199 metabolome, observed at 30 °C and 37 °C, are suggestive of modifications propaedeutic to a subsequent transition from yeast to hyphal form. The analysis of the metabolites' profiles of C. albicans allows envisaging a molecular model to better describe its ability to sense and adapt to environmental conditions. [ABSTRACT FROM AUTHOR]

Although the preparation of nano‐objects by emulsifier‐free controlled/living radical emulsion polymerization has drawn much attention, the morphologies of these formed objects are difficult to predict and to reproduce because of the much more complex nucleation mechanisms of emulsion polymerization compared to only one self‐assembling nucleation mechanism of controlled radical dispersion polymerization. The present study compares dispersion polymerization with emulsifier‐free emulsion polymerization in terms of nucleation mechanism, polymerization kinetics, and disappearance behavior of the macrochain transfer agent, gel permeation chromatograms curves of the obtained block copolymer as well as the structural and morphological differences between the produced nano‐objects on the basis of published data. Moreover, the effects of the inherently heterogeneous nature of emulsion polymerization on the mechanism of reversible addition‐fragmentation transfer polymerization and the nano‐object morphology are examined, and efficient agitation and adequate solubility of the core‐forming monomer in water are identified as the most crucial factors for the fabrication of nonspherical nano‐objects. [ABSTRACT FROM AUTHOR]

Chlamydia trachomatis is a bacterial obligate intracellular parasite and a significant cause of human disease, including sexually transmitted infections and trachoma. The bacterial RNA polymerase-binding protein DksA is a transcription factor integral to the multicomponent bacterial stress response pathway known as the stringent response. The genome of C. trachomatis encodes a DksA ortholog (DksA Ct) that is maximally expressed at 15–20 h post infection, a time frame correlating with the onset of transition between the replicative reticulate body (RB) and infectious elementary body (EB) forms of the pathogen. Ectopic overexpression of DksA Ct in C. trachomatis prior to RB–EB transitions during infection of HeLa cells resulted in a 39.3% reduction in overall replication (yield) and a 49.6% reduction in recovered EBs. While the overall domain organization of DksA Ct is similar to the DksA ortholog of Escherichia coli (DksA Ec), DksA Ct did not functionally complement DksA Ec. Transcription of dksACt is regulated by tandem promoters, one of which also controls expression of nrdR , encoding a negative regulator of deoxyribonucleotide biosynthesis. The phenotype resulting from ectopic expression of DksA Ct and the correlation between dksACt and nrdR expression is consistent with a role for DksA Ct in the C. trachomatis developmental cycle. [ABSTRACT FROM AUTHOR]

Members of the Cryptococcus species complex stand out by unique virulence factors that allowed evolutionary transition to pathogenesis. Among the factors contributing to cryptococcosis is a morphological transformation into giant (Titan) cells. It remains unclear whether species outside of the C. neoformans/C. gattii species complex are capable of titanization. We utilized two recently developed protocols that allow obtaining Titan cells in vitro to test if titanization occurs in non-C. neoformans/C. gattii species. We find that none of the tested strains, representing 10 species of basidiomycetous yeasts and the ascomycetous yeast Saccharomyces cerevisiae, undergo significant titanization under conditions that promote robust Titan cell formation in C. neoformans/C. gattii species complex. C. terreus formed occasional enlarged cells through a mechanism potentially similar to that of titanization. Our findings suggest that titanization is a rare phenomenon among basidiomycetous yeasts that occurs mostly in members of the C. neoformans/C. gattii species complex.

Amphiphilic block copolymers are known to self-assemble into various morphologies, including ellipsoids, tubular structures, toroids, vesicles, micellar structures. In this paper, we discuss the synthesis of copolymeric nanostructures (CNs) using poly(2-ethyl-2-oxazoline)-block-poly(ε-caprolactone) (PEtOx-b-PCL) amphiphilic block copolymers. Our data indicate that - varying the molecular weight and the number of repeating units dictate the nature of morphology. That is, the formation of self-assembled morphologies from ellipsoid to rod-like architectures are observed in aqueous solution, depending on the mass ratio of the hydrophilic block (fPEtOx). To best of our knowledge, this is the first report on the morphological transitions of PEtOx-b-PCL amphiphilic block copolymer-based CNs with different fPEtOx values in the literature.

The morphological structure of DSPE–PEG/PDLLA–MPEG complex aggregates changing from micelles to vesicles, then to semi-vesicles and finally to mixed micelles, with increasing mass ratio.

ABSTRACT Morphological transition is an important adaptive mechanism in the host invasion process. Wor1 is a conserved fungal regulatory protein that controls the phenotypic switching and pathogenicity of Candida albicans. By modulating growth conditions, we simulated three models of Beauveria bassiana morphological transitions, including CTH (conidia to hyphae), HTC (hyphae to conidia), and BTB (blastospore to blastospore). Disruption of BbWor1 (an ortholog of Wor1) resulted in a distinct reduction in the time required for conidial germination (CTH), a significant increase in hyphal growth, and a decrease in the yield of conidia (HTC), indicating that BbWor1 positively controls conidium production and negatively regulates hyphal growth in conidium-hypha switching. Moreover, ΔBbWor1 prominently decreased blastospore yield, shortened the G0/G1 phase, and prolonged the G2/M phase under the BTB model. Importantly, BbWor1 contributed to conidium-hypha switching and blastospore propagation via different genetic pathways, and yeast one-hybrid testing demonstrated the necessity of BbWor1 to control the transcription of an allergen-like protein gene (BBA_02580) and a conidial wall protein gene (BBA_09998). Moreover, the dramatically weakened virulence of ΔBbWor1 was examined by immersion and injection methods. Our findings indicate that BbWor1 is a vital participant in morphological transition and pathogenicity in entomopathogenic fungi. IMPORTANCE As a well-known entomopathogenic fungus, Beauveria bassiana has a complex life cycle and involves transformations among single-cell conidia, blastospores, and filamentous hyphae. This study provides new insight into the regulation of the fungal cell morphological transitions by simulating three models. Our research identified BbWor1 as a core transcription factor of morphological differentiation that positively regulates the production of conidia and blastospores but negatively regulates hyphal growth. More importantly, BbWor1 affects fungal pathogenicity and the global transcription profiles within three models of growth stage transformation. The present study lays a foundation for the exploration of the transition mechanism of entomopathogenic fungi and provides material for the morphological study of fungi.

The ubiquitous commensal Candida albicans, part of the human microbiota, is an opportunistic pathogen able to cause a wide range of diseases, from cutaneous mycoses to life-threatening infections in immunocompromised patients. Candida albicans adapts to different environments and survives long-time starvation. The ability to switch from yeast to hyphal morphology under specific environmental conditions is associated with its virulence. Using hydrogen nuclear magnetic resonance spectroscopy, we profiled the intracellular and extracellular metabolome of C. albicans kept in water, yeast extract–peptone–dextrose (YPD), and M199 media, at selected temperatures. Experiments were carried out in hypoxia to mimic a condition present in most colonized niches and fungal infection sites. Comparison of the intracellular metabolites measured in YPD and M199 at 37 °C highlighted differences in specific metabolic pathways: (i) alanine, aspartate, glutamate metabolism, (ii) arginine and proline metabolism, (iii) glycerolipid metabolism, attributable to the diverse composition of the media. Moreover, we hypothesized that the subtle differences in the M199 metabolome, observed at 30 °C and 37 °C, are suggestive of modifications propaedeutic to a subsequent transition from yeast to hyphal form. The analysis of the metabolites’ profiles of C. albicans allows envisaging a molecular model to better describe its ability to sense and adapt to environmental conditions.

Summary of main observation and conclusion: In this paper, we reported a systematic study on the formation mechanism of bent toroidal micelles from a triblock copolymer poly(acrylic acid)‐block‐(2‐cinnamoyloxylethyl methacrylate)‐block‐poly(perfluorooctylethyl methacrylate) (PAA‐b‐PCEMA‐b‐ PFMA) in the binary solvent mixture of methanol and α,α,α‐trifluorotoluene (MeOH/TFT) through a heating‐cooling procedure. It was found that the formation process of toroids was predominantly kinetic‐controlled, and can be influenced by the preparation protocol, solvent composition and stirring rate of the solutions. The toroids were formed via a complicated morphological transition process. At high temperature, the polymer formed bilayered vesicles with bumpy surface, while upon cooling, the vesicles broke and unfolded into bumpy platelet micelles, which subsequently perforated into toroidal and cylindrical micelles upon further cooling. Besides the distinct and unique bumpy vesicle and platelet structures, the transformation mechanisms from vesicular to platelet, and toroidal micelles are also very intriguing, and may provide new insights into the interconversion of micellar morphologies. [ABSTRACT FROM AUTHOR]

The corn smut fungus Ustilago maydis serves as a model species for studying fungal dimorphism and its role in phytopathogenic development. The pathogen has two growth phases: a saprobic yeast phase and a pathogenic filamentous phase. Dimorphic transition of U. maydis involves complex processes of signal perception, mating, and cellular reprogramming. Recent advances in improvement of reference genomes, high-throughput sequencing and molecular genetics studies have been expanding research in this field. However, the biology of other non-model species is frequently overlooked. This leads to uncertainty regarding how much of what is known in U. maydis is applicable to other dimorphic fungi. In this review, we will discuss dimorphic fungi in the aspects of physiology, reproductive biology, genomics, and molecular genetics. We also perform comparative analyses between U. maydis and other fungi in Ustilaginomycotina, the subphylum to which U. maydis belongs. We find that lipid/hydrophobicity is a potential common cue for dimorphic transition in plant-associated dimorphic fungi. However, genomic profiles alone are not adequate to explain dimorphism across different fungi. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: In this paper, we reported a systematic study on the formation mechanism of bent toroidal micelles from a triblock copolymer poly(acrylic acid)‐block‐(2‐cinnamoyloxylethyl methacrylate)‐block‐poly(perfluorooctylethyl methacrylate) (PAA‐b‐PCEMA‐b‐ PFMA) in the binary solvent mixture of methanol and α,α,α‐trifluorotoluene (MeOH/TFT) through a heating‐cooling procedure. It was found that the formation process of toroids was predominantly kinetic‐controlled, and can be influenced by the preparation protocol, solvent composition and stirring rate of the solutions. The toroids were formed via a complicated morphological transition process. At high temperature, the polymer formed bilayered vesicles with bumpy surface, while upon cooling, the vesicles broke and unfolded into bumpy platelet micelles, which subsequently perforated into toroidal and cylindrical micelles upon further cooling. Besides the distinct and unique bumpy vesicle and platelet structures, the transformation mechanisms from vesicular to platelet, and toroidal micelles are also very intriguing, and may provide new insights into the interconversion of micellar morphologies. [ABSTRACT FROM AUTHOR]

Amphiphilic block copolymers are known to self-assemble into various morphologies, including ellipsoids, tubular structures, toroids, vesicles, micellar structures. In this paper, we discuss the synthesis of copolymeric nanostructures (CNs) using poly(2-ethyl-2-oxazoline)-block-poly(e-caprolactone) (PEtOx-b-PCL) amphiphilic block copolymers. Our data indicate that - varying the molecular weight and the number of repeating units dictate the nature of morphology. That is, the formation of self-assembled morphologies from ellipsoid to rod-like architectures are observed in aqueous solution, depending on the mass ratio of the hydrophilic block (fPEtOx). To best of our knowledge, this is the first report on the morphological transitions of PEtOx-b-PCL amphiphilic block copolymer-based CNs with different fPEtOx values in the literature. [ABSTRACT FROM AUTHOR]

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Infections caused by emerging fungal pathogens represent a new threat to human health. The yeast Yarrowia (Candida) galli was first described from chicken breast and liver in 2004 and has occasionally been isolated in clinical settings. In this study, we present the first report of a Y. galli isolate from a face granuloma of a woman. Y. galli is unable to grow at human physiological temperature (37 °C). Phenotypic analysis demonstrates that Y. galli can exist as several morphological types, namely fluffy, sticky, tight, and yeast forms, based on their cellular and colony appearances. Interestingly, Y. galli is able to undergo switching among different morphologies. These morphological changes are similar to the switching systems in pathogenic Candida species such as Candida albicans and Candida tropicalis. We further sequenced the genome of the Y. galli isolate. A comparative analysis with pathogenic yeast species indicated that a set of lipid metabolism genes were enriched in Y. galli. Domain enrichment analysis demonstrated that, similar to Candida clade species, the genome of Y. galli maintained several gene families required for virulence. Our biological and genomic analyses provide new insights into the understanding of the biology of Y. galli as either an environmental isolate or a potential human pathogen. [ABSTRACT FROM AUTHOR]

Morphological and Structural transitions during epitaxial growth of surface and interface are an important nanoscal phenomena. Understanding the diffusion of adatom in anisotropic surface on the fcc (110), presents a challenge because of the various processes and energy activation of diffusion. During monolayer formation, adatoms could aggregate and forming islands. the stability of these latter is related the its shapes and adatom bonding. In this work, we used the Kinetic Monte Carlo method, implementing anisotropic bond-breaking model (ABBM) to simulate the evolution of anisotropic islands. In order to discuss the monolayer growing, many parameters are taken into account such as potential barriers, temperatures, deposition rates at fixed coverage of 10% monolayer. [ABSTRACT FROM AUTHOR]

• Investigations of results obtained by KMC simulations during heteroepitaxial growth. • EAM Method is used to compute the activation barriers of different diffusion processes. • All process diffusion is modeled by Anisotropic bond breaking model (ABBM). • Growth conditions effect the surface morphologies evolution for both systems Ag and Au on Cu(1 1 0). In this work, different coverages (1% ≤ coverage ≤ 20%) are studied during the growth of Ag and Au monolayers on the Cu (1 1 0) surface using kinetic Monte Carlo simulations (kMC). The results have shown that as coverage increases, the likelihood of an isolated adatom connecting to another adatom or island also increases. Thus, the phenomenon by which an adatom disintegrates from one island to another becomes significant. Molecular statics method is used to calculate the activation energy barriers of several diffusion processes in the framework of the Embedded-Atom method (EAM). These diffusion processes are implemented in the kinetic Monte Carlo (kMC) simulations under the Anisotropic Bond-Breaking Model (ABBM) model. The results show that as the coverage increases, 1D clusters are observed at 200 K. However, the transition from compact 1D (at 200 K) to 2D islands has been observed for relatively high temperatures (300 K and 400 K). [ABSTRACT FROM AUTHOR]

Candida albicans is a polymorphic opportunistic commensal that causes both superficial and systemic fungal infections especially in immunocompromised patients. Biologically synthesized silver nanoparticles (AgNPs) have emerged as potential antifungal agents. The present work evaluates the antifungal activity of Artemisia annua synthesized AgNPs against three Candida species (C. albicans ATCC 90028, C. tropicalis ATCC 750 and C. glabrata ATCC 90030). The in vitro effect of AgNPs was investigated for fungal growth, sterol content, secretion of hydrolytic enzymes and yeast-to-hyphal transition. The green synthesized AgNPs were effective against all the three species with minimum inhibitory concentration (MIC) in the range 80–120 μgml−1. Candida glabrata showed greater sensitivity for AgNPs followed by Candida tropicalis and C. albicans. AgNPs at 4MIC were as effective as fluconazole (FLC) and caused only 5% haemolysis while FLC caused 50% haemolysis at the same concentration. The secretion of hydrolytic enzymes was the lowest in case of AgNP exposed C. glabrata. Yeast-to-hyphal transition was significantly reduced in treated C. albicans cells and showed disfigured morphology in SEM images. The decrease in ergosterol content was slightly higher (94%) in both C. glabrata and C. tropicalis in comparison to C. albicans (69%). Green synthesized AgNPs thus have immense potential as an antifungal and can play a crucial role in the management of Candida infections especially those caused by C. glabrata. [ABSTRACT FROM AUTHOR]

Loureirin A is a major active component of Draconis sanguis , a traditional Chinese medicine. This work aimed to investigate the activity of loureirin A against Candida albicans biofilms. 2, 3-Bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT)reduction assay and scanning electron microscopy were used to investigate the anti-biofilm effect. Minimal inhibitory concentration testing and time-kill curve assay were used to evaluate fungicidal activity. Cell surface hydrophobicity (CSH) assay and hyphal formation experiment were respectively carried out to investigate adhesion and morphological transition, two virulence traits of C. albicans. Real-time RT-PCR was used to investigate gene expression. Galleria mellonella − C. albicans and Caenorhabditis elegans-C. albicans infection models were used to evaluate the in-vivo antifungal effect. Human umbilical vein endothelial cells and C. elegans nematodes were used to evaluate the toxicity ofloureirin A. Our data indicated that loureirin A had a significant effect on inhibiting C. albicans biofilms, decreasing CSH, and suppressing hyphal formation. Consistently, loureirin A down-regulated the expression of some adhesion-related genes and hypha/biofilm-related genes. Moreover, loureirin A prolonged the survival of Galleria mellonella and Caenorhabditis elegans in C. albicans infection models and exhibited low toxicity. Collectively, loureirin A inhibits fungal biofilms, and this effect may be associated with the suppression of pathogenic traits, adhesion and hyphal formation. [ABSTRACT FROM AUTHOR]

Microphase‐separated structures of a series of AB6 block‐graft copolymers were studied by TEM and SAXS. Ten copolymers with the same polystyrene (S) backbone and six polyisoprene (I) grafts on the average but with different graft chain lengths were carefully synthesized by living anionic polymerization, covering the range 0.21 ≤ ϕS ≤ 0.90, where ϕS denotes polystyrene compositions. From TEM observation of the AB6 block‐graft copolymers, it turns out to be clear that they show four microphase‐separated structures, S‐spheres, S‐cylinders(S‐prisms), alternative lamellae, and I‐cylinders. Among them, for example, the samples with 0.54 ≤ ϕS ≤ 0.58 shows prism structures whose cross sections of the S domains are close to hexagons, not circles, due to packing frustration of grafts. Composition dependence of morphologies of the present AB6 block‐graft copolymers reveals their phase diagram is extremely asymmetric with respect to ϕS = 0.5. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019, 57, 952–960 [ABSTRACT FROM AUTHOR]

Pluronics have emerged as a potential agent for solubilizing a variety of lipophilic bioactive molecules, but how these solubilizates affect the morphology of Pluronic micelles still remains poorly understood. In this work, the morphological transition of Pluronic P123 micelles induced by three gallate homologs with different alkyl chain length, namely methyl gallate (MG), propyl gallate (PG) and octyl gallate (OG) has been comprehensively investigated by combination of dynamic light scattering (DLS), cryogenic transmission electron microscopy (Cryo-TEM), 1H NMR and atom-scale molecular dynamic simulations. It is found that addition of the three gallate significantly increases the micellar sizes and polydispersities. Cryo-TEM measurements reveal that spherical P123 micelles form micellar clusters in the presence of PG and short rod micelles with OG, while MG do not change the micellar morphology. Qualitative interactions between various gallate and P123 micelle are determined by NMR experiments. It is demonstrated that the different locations of various gallate in the micelles are governed by the balance of hydrophobic interaction and hydrogen bonding, which consequently leads to the varying micellar morphologies. The experimental results are further confirmed by dynamic molecular stimulation. We also show that the intensity of Pluronic-gallate interaction increases with the hydrophobicity of the gallate, indicating that hydrophobic interaction is more important on the morphological transition. Finally, the mechanism of morphological transition induced by various gallate are discussed and proposed, where the nature of formation of micellar cluster induced by PG is particularly emphasized. [ABSTRACT FROM AUTHOR]

Vitronectin (Vtn), one of the extracellular matrix proteins, has been reported to result in cell cycle exit, neurite formation, and polarization of neural progenitor cells during neurogenesis. The underlying mechanism, however, has not been fully understood. In this study, we investigated the roles of Vtn and its integrin receptors, during the transition of neurites from multipolar to bipolar morphology, accompanying the cell cycle exit in neural progenitor cells. We used mouse neuroblastoma cell line Neuro2a as a model of neural progenitor cells which can induce cell cycle exit and the morphological transition of neurites by retinoic acid (RA)-stimulation. Treatment with an antibody for Vtn suppressed the RA-induced cell cycle exit and multipolar-to-bipolar transition. Furthermore, immunostaining results showed that in the cells displaying multipolar morphology Vtn was partially localized at the tips of neurites and in cells displaying bipolar morphology at both tips. This Vtn localization and multipolar-to-bipolar transition was perturbed by the transfection of a dominant negative mutant of cell polarity regulator Par6. In addition, a knockdown of β5 integrin, which is a receptor candidate for Vtn, affected the multipolar-to-bipolar transition. Taken together, these results suggest that Vtn regulates the multipolar-to-bipolar morphological transition via αvβ5 integrin. [ABSTRACT FROM AUTHOR]

Abstract The aqueous solutions of PEO-PPO-PEO type triblock copolymers (Pluronic® P123, P103 and P105) with variations in their total molecular weight and block contribution are investigated for encapsulation of drugs. Two drugs, namely Aspirin (AS) and 5-Methyl Salicylate (MS) having different partition coefficient was studied. The changes in size and micellar dynamics due to formation of drug-polymer complexes are investigated using dynamic light scattering (DLS), dynamic surface tension (DST), Nuclear Magnetic Resonance (NMR) and Small angle neutron scattering (SANS) measurements. Increase in apparent hydrodynamic diameter (D h) measured by DLS suggests the growth of micelles, which is equally supported by calculated micellar parameters from SANS measurements. The solubilization of drugs within micelles alters the diffusivity of the monomers due to stronger hydrophobic forces leading to highly stable aggregates as concluded by dynamic surface tension measurements. The significant increase in micellar size was noticed in presence of MS, while AS had less prominent effect on micellar growth. The preferential partitioning of drug into the hydrophobic micellar core is the driving force for the possible formation of higher morphologies. The hydrophobic interactions between MS and P123 are confirmed by 1H NMR. The differences in molecular interactions leading to distinct morphological behavior are explained by the localization of drug within nanocarriers. Graphical abstract Unlabelled Image Highlights • Salicylic acid analogues affect the micellar structures of Pluronics®. • 5-Methyl salicylate exert stronger alterations compared to Aspirin. • Molecularly dissolved drug decreases diffusivity of copolymer molecules in bulk. • The SANS reveals transformation of micellar aggregates to ellipsoidal structure. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Elucidation of the effect of electrolytes towards the morphology of OTAB micelles. • Monomeric salts induce monotonous micellar swelling. • Effect of the monomeric salts has been explained by the co-sphere overlap model. • Polymeric salt induce minute micellar growth followed by phase separation. • A novel two-step model has been invoked for the polymeric salt-induced changes. Abstract The discrete effects of a series of structurally divergent monomeric viz. Sodium Chloride (NaCl), Tetra-butyl Ammonium Chloride (TBAC) and Sodium Benzoate (NaBz) and polymeric viz. Sodium Polystyrene Sulfonate (NaPSS) electrolytes towards the morphological and/or aggregation properties of Octadecyl-trimethyl Ammonium Bromide (OTAB) micelles have been quantified spectroscopically by means of the modulations of the absorption and emission spectral properties of an extrinsic anthracene-based probe 9-methyl anthroate (9-MA) within the concerned media. Further corroboration of the spectroscopic results was acquired from the non-invasive dynamic light scattering technique. The qualitatively similar mode of action of all the monomeric salts has been explained on the basis of the archetypal Israelachvili model whereas the corresponding extent of the morphological transition of the micelles, which is found to follow the order NaBz > NaCl > TBAC, has been explained invoking the co-sphere overlap model. Conversely, to explain the aggregation behaviour of the micelles in the presence of the polymeric electrolyte, a two-step model has been formulated. According to this model, at the low concentration regime, the polymeric salt is found to only neutralize the surface charge of the micelles inducing micellar growth; whereas further increment in the concentration of the polymer assists the hydrophobic association between the micelles leading to the formation of larger aggregates, eventually causing a phase separation. [ABSTRACT FROM AUTHOR]

The morphological transition from yeast to a hyphal form, as well as the adhesion capability to the gastrointestinal tract, are implicated virulent determinant in Candida albicans and could be potential targets for prevention of the opportunistic pathogen. Based on this rationale, two yeast strains Saccharomyces cerevisiae KTP and Issatchenkia occidentalis ApC along with reference strain Saccharomyces boulardii NCDC 363 were screened for the probiotic potential. Characters like pH, temperature, bile, simulated gastrointestinal juice tolerance tests, and Caco-2 cell line adhesion assay were determined in the present study. Further, the evaluation of its impact on C. albicans morphological transition and adhesion was assessed using microtitre germ tube test. In terms of probiotic characteristics, both the strains were tolerant to pH 2.5 and the presence of bile (0.3 to 0.6%) with an optimum growth temperature of 37°C. The strain KTP was also resistant to simulated gastric and intestinal juices as compared to control (13% and 41%, respectively) and NCDC 363 (55% and 35%, respectively). In contrast, both the yeasts had reduced adhesiveness to Caco-2 monolayer. Candida virulence in in vitro systems indicated that treatment of live probiotic yeast cells (108ml) effectively reduced the filamentation and adhesion of C. albicans. The S. cerevisiae KTP had a profound effect on the hyphal development and adhesion when compared to the ApC and NCDC 363. The strain significantly reduced (P <.05) the hyphal growth in co-cultivated (93% and 94%, respectively) and pre-existing hyphae (54% and 68%) of strains C. albicans 183 and 1151. Isolates KTP and ApC also reduced the adhesion (≈ 22% and 41%, respectively) and transition of blastoconidia at two hours of incubation in abiotic surface. This study provides knowledge on the effect of potential probiotic yeasts such as Saccharomyces and non- Saccharomyces strains against virulence characteristic of Candida albicans. [ABSTRACT FROM AUTHOR]

Although gas-filled microbubbles with high echogenicity are widely applied inclinical ultrasonography, the micron scale particle size impedes their use in the treatment of solid tumors,which are accessible to objects less than several hundred nanometers. We herein propose an unusual approach involving apH-induced core-shell micelle-to-vesicle transition to prepare ultrasound-sensitive polymeric nanospheres (polymersomes in structure) possessing multiple features, including nanosize, monodispersity, and incorporation of a phase-transitional imaging agent into the aqueous lumen. These features are not achievable via the conventional double-emulsion method for polymersome preparation. The nanospheres were constructed based on a novel triblock copolymer with dual pH sensitivity. The liquid-to-gas phase transition of the imaging agent induced by external low-frequency ultrasound may destroy the nanospheres for a rapid drug release, with simultaneous tissue-penetrating drug delivery inside a tumor. These effects may provide new opportunities for the development of an effective cancer therapy with few adverse effects. [ABSTRACT FROM AUTHOR]

The co-assembly process is an effective approach to construct hierarchically nanostructured soft materials, but morphological transition of co-assemblies upon external stimuli, particularly the 'green' trigger CO2, is not unraveled yet. Here, a segmented copolymer, poly(styrene)- block-poly[(4-vinyl pyridine)- random-((2-(diethylamino)ethyl methacrylate)] (P1), is used to co-assemble in the mixed solvent of dimethyl formamide and water with poly(ethylene oxide)- block-poly[(4-vinyl pyridine)- random-((2-(diethylamino)ethyl methacrylate)] (P2) and poly(ethylene oxide)- block-poly(acrylic acid) (P3), respectively. It is found that Janus micelles are generated from the P1-P2 pair in the presence of ferric ion, while wormlike micelles are formed from the P1-P3 duad. Upon stimulation with CO2, Janus and wormlike aggregates are transferred into core-shell and spherical micelles, respectively. [ABSTRACT FROM AUTHOR]

Surface antigen protein 2 (Csa2) is a member of the Candida albicans Common in Fungal Extracellular Membranes (CFEM) protein superfamily. We previously establishedits role in iron acquisition in C. albicans. However, the other roles of Csa2 remain unknown. Here, we comparedgrowth, morphological transition, andbiofilm formation among wild-type, Csa2-mutant, andcomplementedstrains of C. albicans. Deletion of the Csa2 gene resultedin smaller andreducedcolony growth, significant attenuation of the dimorphic transition under serum-inducing conditions, and reduced biofilm formation; complementation restored these levels to those of the wild-type. Our findings demonstrated that Csa2 participated in yeast-to-hyphae morphological switching under serum-inducing conditions and contributedto the biofilm formation of C. albicans. This work, therefore, provides novel insights into the potential roles of Csa2 in virulence of C. albicans. [ABSTRACT FROM AUTHOR]

A novel low molecular weight organogelator (LMOG) containing an azobenzene group has been designed and synthesized. Stable gels could be formed in various organic solvents. UV–Vis spectroscopy indicated that the sol-gel transition of the organogels could be reversibly tuned by UV/visible light irradiations. Importantly, scanning electron microscopy (SEM) revealed that the characteristic gelation morphologies would vary from solvents of different polarities. FT-IR, XRD and rheological measurements demonstrated that the different nanostructures in polar and non-polar solvents might result from the differences in the intermolecular hydrogen bonding, π-π stacking driving forces as well as the different stacking models for the formation of the gels. Moreover, as an efficient phase-selective gelator, this photo-switchable gel could perform as an efficient absorbent and water cleaner to remove pollutants (e.g. rhodamine B). [ABSTRACT FROM AUTHOR]

We report experimental results of time-resolved 2d-SAXS measurements for a polystyrene- block -poly(ethylene- co -butylene)- block -polystyrene (SEBS) triblock copolymer as-cast film, which was subjected to a planar flow gradually imposed in the heating process of the specimen at a ramp-up rate of 2 °C/min. Before heating, non-equilibrium spheres were formed in the specimen. At 144 °C, the spheres were found to completely transform into cylinders. Some extent of cylinder orientation (0.5 in orientation factor) was already achieved, even at that temperature the strain of the specimen was as low as 0.5. From this fact, the directional coalescence of non-equilibrium spheres along with the planar flow direction (FD) was implied. As temperature increased, it was found the progress of the cylinder orientation parallel to FD as well as the orientation of the ( 1 0 1 ¯ 0 ) planes of hexagonal lattice parallel to the substrate surface. The fraction of the peak-top intensities of the ( 1 1 2 ¯ 0 ) reflections, I ( 11 2 ¯ 0 ) / ( I ( 10 1 ¯ 0 ) + I ( 11 2 ¯ 0 ) ) , was evaluated to examine the change in the orientational state of hexagonal lattice during application of the planar flow. The fraction was found to moderately increase with strain. However, the fraction of the grains, in which the ( 1 0 1 ¯ 0 ) planes are parallel to the specimen surface, is as low as 0.07 even at the highest strain state. [ABSTRACT FROM AUTHOR]