The in vitro activity of the imidazolium salt C₁₆MImCl against planktonic and biofilm cells of multidrug‐resistant isolates of Candida tropicalis was evaluated, both in solution and applied on a ...commercial catheter surface. This was determined by inhibition and susceptibility assays of biofilm and planktonic cells. In both cases, C₁₆MImCl prevented in vitro biofilm formation of C. tropicalis strains, including multidrug‐resistant ones. Outstanding performances were observed, even at extremely low concentrations. Furthermore, this is the first report of the antifungal lock property of C₁₆MImCl, using a tracheal catheter as the test specimen to mimic a clinical in vivo condition. As such, C₁₆MImCl has been identified as a promising antimicotic pharmaceutical candidate for the treatment of candidiasis infections. SIGNIFICANCE AND IMPACT OF THE STUDY: The imidazolium salt 1‐n‐hexadecyl‐3‐methylimidazolium chloride (C₁₆MImCl) strongly prevents, in concentrations as low as 0·028 μg ml⁻¹, the biofilm formation of multidrug‐resistant Candida tropicalis isolates, either in solution or applied on the surface of commercial catheters. This presents an effective antimicotic candidate and alternative for invasive clinical procedure toolset asepsis.
Undeniably, new antifungal treatments are necessary against pathogenic fungi. Fungal infections have significantly increased in recent decades, being highlighted as important causes of morbidity and ...mortality, particularly in immunocompromised patients. Five main antifungal classes are used: (i) azoles, (ii) echinocandins, (iii) polyenes, (iv) allylamines and (v) pyrimidine analogues. Moreover, the treatment of mycoses has several limitations, such as undesirable side effects, narrow activity spectrum, a small number of targets and fungal resistance, which are still of major concern in clinical practice. The discovery of new antifungals is mostly achieved by the screening of natural or synthetic/semisynthetic chemical compounds. The most recent discoveries in drug resistance mechanism and their avoidance were explored in a review, focusing on different antifungal targets, as well as new agents or strategies, such as combination therapy, that could improve antifungal therapy.
Significance and Impact of the Study
The failure to respond to antifungal therapy is complex and is associated with microbiological resistance and increased expression of virulence in fungal pathogens. Thus, this review offers an overview of current challenges in the treatment of fungal infections associated with increased antifungal drug resistance and the formation of biofilms in these opportunistic pathogens. Furthermore, the most recent and potential strategies to combat fungal pathogens are explored here, focusing on new agents as well as innovative approaches, such as combination therapy between antifungal drugs or with natural compounds.
Significance and Impact of the Study: The failure to respond to antifungal therapy is complex and is associated with microbiological resistance and increased expression of virulence in fungal pathogens. Thus, this review offers an overview of current challenges in the treatment of fungal infections associated with increased antifungal drug resistance and the formation of biofilms in these opportunistic pathogens. Furthermore, the most recent and potential strategies to combat fungal pathogens are explored here, focusing on new agents as well as innovative approaches, such as combination therapy between antifungal drugs or with natural compounds.
Direct arylation of 5-octylthieno3,4-cpyrrole-4,6-dione with a series of functionalized aryl iodides via C–H bond activation is demonstrated in a deep eutectic solvent made of choline chloride and ...urea in non-anhydrous conditions and without exclusion of air. This is the first demonstration of a thiophene–aryl coupling via direct arylation in deep eutectic solvents.
In recent years, considerable effort has been devoted to the synthesis and characterization of two-dimensional materials. Liquid phase exfoliation (LPE) represents a simple, large-scale method to ...exfoliate layered materials down to mono- and few-layer flakes. In this context, the contactless trapping, characterization, and manipulation of individual nanosheets hold perspectives for increased accuracy in flake metrology and the assembly of novel functional materials. Here, we use optical forces for high-resolution structural characterization and precise mechanical positioning of nanosheets of hexagonal boron nitride, molybdenum disulfide, and tungsten disulfide obtained by LPE. Weakly optically absorbing nanosheets of boron nitride are trapped in optical tweezers. The analysis of the thermal fluctuations allows a direct measurement of optical forces and the mean flake size in a liquid environment. Measured optical trapping constants are compared with T-matrix light scattering calculations to show a quadratic size scaling for small size, as expected for a bidimensional system. In contrast, strongly absorbing nanosheets of molybdenum disulfide and tungsten disulfide are not stably trapped due to the dominance of radiation pressure over the optical trapping force. Thus, optical forces are used to pattern a substrate by selectively depositing nanosheets in short times (minutes) and without any preparation of the surface. This study will be useful for improving ink-jet printing and for a better engineering of optoelectronic devices based on two-dimensional materials.
Abstract
Cosmic dust plays a dominant role in the universe, especially in the formation of stars and planetary systems. Furthermore, the surface of cosmic dust grains is the benchwork where molecular ...hydrogen and simple organic compounds are formed. We manipulate individual dust particles in a water solution by contactless and noninvasive techniques such as standard optical and Raman tweezers, to characterize their response to mechanical effects of light (optical forces and torques) and to determine their mineral compositions. Moreover, we show accurate optical force calculations in the T-matrix formalism highlighting the key role of composition and complex morphology in the optical trapping of cosmic dust particles. This opens perspectives for future applications of optical tweezers in curation facilities for sample-return missions or in extraterrestrial environments.
One important aspect of Bayesian model selection is how to deal with huge model spaces, since the exhaustive enumeration of all the models entertained is not feasible and inferences have to be based ...on the very small proportion of models visited. This is the case for the variable selection problem with a moderately large number of possible explanatory variables considered in this article. We review some of the strategies proposed in the literature, from a theoretical point of view using arguments of sampling theory and in practical terms using several examples with a known answer. All our results seem to indicate that sampling methods with frequency-based estimators outperform searching methods with renormalized estimators. Supplementary materials for this article are available online.
We demonstrate optical trapping of plasmonic silica-gold mesocapsules and their use as local SERS probes in Raman tweezers. These novel hybrid dielectric-metal particles, designed for optoplasmonic ...applications, are mesoscopic porous silica shells embedding gold nanospheres in their inner wall. We observe a high trapping efficiency due to plasmon-enhanced optical trapping of the gold component. Furthermore, we develop an accurate model of optical trapping of this hybrid system in the T-matrix framework studying how the plasmon-enhanced optical forces scale with gold nanoparticle number in the mesocapsule. The relevance of effective optical trapping in hollow plasmonic mesocapsules is twofold for detection and delivery technologies: positioning and activation processes. In fact, the presented system allows for the opportunity to drag and locate cargo mesocapsules embedded with specific molecules that can be activated and released in situ when a precise localization is required.
Background
Ultrarare Marshall–Smith and Malan syndromes, caused by changes of the gene nuclear factor I X (NFIX), are characterised by intellectual disability (ID) and behavioural problems, although ...questions remain. Here, development and behaviour are studied and compared in a cross‐sectional study, and results are presented with genetic findings.
Methods
Behavioural phenotypes are compared of eight individuals with Marshall‐Smith syndrome (three male individuals) and seven with Malan syndrome (four male individuals). Long‐term follow‐up assessment of cognition and adaptive behaviour was possible in three individuals with Marshall–Smith syndrome.
Results
Marshall–Smith syndrome individuals have more severe ID, less adaptive behaviour, more impaired speech and less reciprocal interaction compared with individuals with Malan syndrome. Sensory processing difficulties occur in both syndromes. Follow‐up measurement of cognition and adaptive behaviour in Marshall–Smith syndrome shows different individual learning curves over time.
Conclusions
Results show significant between and within syndrome variability. Different NFIX variants underlie distinct clinical phenotypes leading to separate entities. Cognitive, adaptive and sensory impairments are common in both syndromes and increase the risk of challenging behaviour. This study highlights the value of considering behaviour within developmental and environmental context. To improve quality of life, adaptations to environment and treatment are suggested to create a better person‐environment fit.
Aims
Evaluate the in vitro effect of imidazolium salts (IMS) on the conidia germination and mycelial growth of Fusarium graminearum and their in vivo efficacy for suppressing the symptoms of the ...disease and infection of kernels in wheat plants.
Methods and Results
The minimum inhibitory concentrations (MIC) of three IMS (C16MImCl, C16MImMeS and C16MImNTf2) were determined for four F. graminearum isolates using serial broth dilution method. The MICs found for all IMS were either 3·12 or 6·25 μg ml−1 across the isolates, with the former as the most frequent. In the mycelial growth assay on potato dextrose agar media, only the C16MImCl among the IMS reduced 50% of mycelial growth of one isolate at an estimated concentration of 0·32 mg ml−1. The time‐kill curves showed a strong fungicidal effect starting 1 h after incubation at a concentration of 12·5 μg ml−1, representing a fourfold increase in the most frequent MIC. The C16MImCl sprayed onto the spikes of potted wheat plants during the flowering stage reduced disease intensity at levels comparable to the commercial fungicide when applied preventatively (1 h prior to fungal inoculation), rather than curatively, and at the higher dosage (2 mg ml−1) rather than lower dosage (0·5 mg ml−1).
Conclusions
C16MImCl proved to be a potent inhibitor of F. graminearum growth and provided good levels of control of the disease at levels comparable to a commercial fungicide, in wheat plants treated prior to fungal infection during flowering stages.
Significance and Impact of the Study
This study suggests the potential of using IMS as alternative to the hazardous standard fungicides in the management of Fusarium head blight of wheat.
•TNF-α system members are expressed at different follicular stages in bovine ovaries.•TNF-α reduces follicular survival in cultured bovine ovarian tissue.•TNF-α increases the total number of ...apoptotic cells in cultured follicles.•Dexamethasone improves ultrastructure of bovine follicle cultured in vitro.
This study was conducted to detect the protein expression of TNF-α system members (TNF-α/TNFR1/TNFR2) in bovine ovarian follicles and to evaluate the effects of TNF-α or dexamethasone on the survival and growth of primordial follicles in vitro, as well as on gene expression in cultured ovarian tissue. It was hypothesized that TNF-α induces follicular atresia in ovarian tissues cultured in vitro, and that dexamethasone suppresses the production of endogenous TNF-α, which can improve follicle viability in vitro. Ovarian fragments were cultured for 6days in α-MEM+ supplemented with TNF-α (0, 1, 10, 100 or 200ng/ml) or dexamethasone (0, 1, 10, 100 or 200ng/ml). After culture, the expression of mRNAs for BCL-2, BAX, P53, TNF-α, and CASP3 and CASP6 were evaluated. Immunohistochemical results showed that the TNF-α system members, were detected in bovine preantral and antral follicles. After 6days, the TNF-α (10ng/ml) treatment reduced the percentage of normal preantral follicles and increased the number of TUNEL-positive cells in cultured tissue. Dexamethasone (10ng/ml) during 6days of culture did maintain the percentage of normal follicles and the ultrastructure of follicles, while the presence of TNF-α or dexamethasone did not influence primordial follicle activation. However, TNF-α or dexamethasone had no effect on the levels of mRNA for P53, BCL-2, BAX and CASP6, in cultured tissues, but the presence of dexamethasone reduced the levels of CASP3 compared to ovarian slices cultured in control medium (α-MEM+). In conclusion, proteins of the TNF-α system are expressed at different bovine follicle stages. The addition of TNF-α in culture reduces follicle survival and increases the number of apoptotic cells in ovarian tissue, while the presence of dexamethasone maintains follicle ultrastructure in cultured tissue.
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