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The object of this work is to prepare quinoxaline-based benzoxazines and evaluate thermal properties of their thermosets. For this object, 4,4'-(quinoxaline-2,3-diyl)diphenol (QDP)/furfurylamine-based benzoxazine (QDP-fu) and 4,4',4″,4‴-([6,6'-biquinoxaline]-2,2',3,3'-tetrayl)tetraphenol (BQTP)/furfurylamine-based benzoxazine (BQTP-fu) were prepared. The structures of QDP-fu and BQTP-fu were successfully confirmed by FTIR and 1H and 13C NMR spectra. We studied the curing behavior of QDP-fu and BQTP-fu and thermal properties of their thermosets. According to DSC thermograms, QDP-fu and BQTP-fu have the attractive onset exothermic temperatures of 181 and 186 °C, respectively. The onset temperature is approximately 45 °C lower than that of a bisphenol A/furfurylamine-based benzoxazines. According to DMA TMA and TGA thermograms, the thermoset of BQTP-fu shows impressive thermal properties, with a T g value of 418 °C, a coefficient of thermal expansion of 39 ppm/°C, a 5% decomposition temperature of 430 °C, and a char yield of 72%.

Candida albicans is a leading cause of intravascular catheter-related infections. The capacity for biofilm formation has been proposed to contribute to the persistence of this fungal pathogen on catheter surfaces. While efforts have been devoted to identifying microbial factors that modulate C. albicans biofilm formation in vitro, our understanding of the host factors that may shape C. albicans persistence in intravascular catheters is lacking. Here, we used multiphoton microscopy to characterize biofilms in intravascular catheters removed from candidiasis patients. We demonstrated that, NETosis, a type of neutrophil cell death with antimicrobial activity, was implicated in the interaction of immune cells with C. albicans in the catheters. The catheter isolates exhibited reduced filamentation and candidalysin gene expression, specifically in the total parenteral nutrition culture environment. Furthermore, we showed that the ablation of candidalysin expression in C. albicans reduced NETosis and conferred resistance to neutrophil-mediated fungal biofilm elimination. Our findings illustrate the role of neutrophil NETosis in modulating C. albicans biofilm persistence in an intravascular catheter, highlighting that C. albicans can benefit from reduced virulence expression to promote its persistence in an intravascular catheter. Author summary: Intravascular catheters are widely used to administer medication and provide nutritional support to patients. However, their clinical use also increases the incidence of bloodstream infections and constitutes a risk factor for Candida albicans infection. Microbial biofilms have been proposed as the primary living style of microbes on a surface, including those on intravascular catheters. Numerous studies focus on identifying microbial factors contributing to C. albicans biofilm formation. However, our understanding of the host factors involved in controlling C. albicans biofilms on the surface of intravascular catheters is limited. In this study, we demonstrated that the biofilms in intravascular catheters removed from candidiasis patients comprised not only C. albicans cells but also human immune cells. Among these catheters, the immune cells interacting with the fungus exhibited different properties of NETosis, a type of neutrophil cell death with antimicrobial activity. We further showed that the catheter isolates exhibited reduced expression of candidalysin. Supplementation of candidalysin promoted NETosis induced by C. albicans biofilms and diminished C. albicans biofilms on a surface. Our findings highlight the implication of neutrophils in eliminating C. albicans biofilms, and point out the benefit of reduced candidalysin expression for C. albicans to persist in intravascular catheters. [ABSTRACT FROM AUTHOR]

Candida albicans can stochastically switch between two phenotypes, white and opaque. Opaque cells are the sexually competent form of C. albicans and therefore undergo efficient polarized growth and mating in the presence of pheromone. In contrast, white cells cannot mate, but are induced - under a specialized set of conditions - to form biofilms in response to pheromone. In this work, we compare the genetic regulation of such "pheromone-stimulated" biofilms with that of "conventional" C. albicans biofilms. In particular, we examined a network of six transcriptional regulators (Bcr1, Brg1, Efg1, Tec1, Ndt80, and Rob1) that mediate conventional biofilm formation for their potential roles in pheromone-stimulated biofilm formation. We show that four of the six transcription factors (Bcr1, Brg1, Rob1, and Tec1) promote formation of both conventional and pheromone-stimulated biofilms, indicating they play general roles in cell cohesion and biofilm development. In addition, we identify the master transcriptional regulator of pheromone-stimulated biofilms as C. albicans Cph1, ortholog of Saccharomyces cerevisiae Ste12. Cph1 regulates mating in C. albicans opaque cells, and here we show that Cph1 is also essential for pheromone-stimulated biofilm formation in white cells. In contrast, Cph1 is dispensable for the formation of conventional biofilms. The regulation of pheromone- stimulated biofilm formation was further investigated by transcriptional profiling and genetic analyses. These studies identified 196 genes that are induced by pheromone signaling during biofilm formation. One of these genes, HGC1, is shown to be required for both conventional and pheromone-stimulated biofilm formation. Taken together, these observations compare and contrast the regulation of conventional and pheromone-stimulated biofilm formation in C. albicans, and demonstrate that Cph1 is required for the latter, but not the former.

This study explores issues on post-adoption services in intercountry adoptions based on the perspectives of adoption professionals from Taiwan and Australia. Findings revealed that both birth and adoptive families identify service needs for material and emotional support and connection after the adoption process is finalized. However, the current lack of government funding for post-adoption services result in gaps in service delivery. Adoption agencies experience challenges in funding and balancing the interests of the child and the two families. Implications for practice and policy are discussed to enhance the quality of post-adoption services and improve the well-being of the adoption triad. [ABSTRACT FROM AUTHOR]