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In actinobacteria, an OmpR/PhoB subfamily protein called GlnR acts as an orphan response regulator and globally coordinates the expression of genes responsible for nitrogen, carbon, and phosphate metabolism in actinobacteria. Although many researchers have attempted to elucidate the mechanisms of GlnR-dependent transcription activation, progress is impeded by lacking of an overall structure of GlnR-dependent transcription activation complex (GlnR-TAC). Here, we report a co-crystal structure of the C-terminal DNA-binding domain of GlnR (GlnR_DBD) in complex with its regulatory cis -element DNA and a cryo-EM structure of GlnR-TAC which comprises Mycobacterium tuberculosis RNA polymerase, GlnR, and a promoter containing four well-characterized conserved GlnR binding sites. These structures illustrate how four GlnR protomers coordinate to engage promoter DNA in a head-to-tail manner, with four N-terminal receiver domains of GlnR (GlnR-RECs) bridging GlnR_DBDs and the RNAP core enzyme. Structural analysis also unravels that GlnR-TAC is stabilized by complex protein–protein interactions between GlnR and the conserved β flap, σ A R4, αCTD, and αNTD domains of RNAP, which are further confirmed by our biochemical assays. Taken together, these results reveal a global transcription activation mechanism for the master regulator GlnR and other OmpR/PhoB subfamily proteins and present a unique mode of bacterial transcription regulation.

In Aspergillus fumigatus, the most prevalent resistance to azoles results from mutational modifications of the azole target protein Cyp51A, but there are non

Rapid identification of microorganisms in urine is essential for patients with urinary tract infections (UTIs). Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been proposed as a method for the direct identification of urinary pathogens. Our purpose was to compare centrifugation-based MALDI-TOF MS and short-term culture combined with MALDI-TOF MS for the direct identification of pathogens in urine specimens. We collected 965 urine specimens from patients with suspected UTIs, 211/965 isolates were identified as positive by conventional urine culture. Compared with the conventional method, the results of centrifugation-based MALDI-TOF MS were consistent in 159/211 cases (75.4%), of which 135/159 (84.9%) had scores ≥ 2.00; 182/211 cases (86.3%) were detected using short-term culture combined with MALDI-TOF MS, of which 153/182 (84.1%) had scores ≥ 2.00. There were no apparent differences among the three methods (p = 0.135). MALDI-TOF MS appears to accelerate the microbial identification speed in urine and saves at least 24 to 48 hours compared with the routine urine culture. Centrifugation-based MALDI-TOF MS is characterized by faster identification speed; however, it is substantially affected by the number of bacterial colonies. In contrast, short-term culture combined with MALDI-TOF MS has a higher detection rate but a relatively slow identification speed. Combining these characteristics, the two methods may be effective and reliable alternatives to traditional urine culture.

Invasive Aspergillus fumigatus infection is a disease with high morbidity and mortality rates. Abnormalities in sporulation and pigmentation can significantly alter the pathogenicity of A. fumigatus, thus the mechanisms of conidiation and pigment biosynthesis have gained increasing attention. In Aspergillus oryzae, a novel predicted bHLH protein-encoding gene, ecdR, plays a role in asexual development, and its ortholog has also been characterized in A. nidulans. Herein, we determined its role in A. fumigatus by testing whether ecdR deletion affects asexual development, melanin synthesis, and regulation of virulence in this fungus. Our study shows that EcdR controls conidia and melanin production in A. fumigatus. In addition, we found that virulence in the ΔecdR strain was significantly reduced in the infection model of immunodeficiency mice.

Aspergillus fumigatus is a pathogenic fungus responsible for invasive aspergillosis (IA). Typically, it can produce abundant conidia to survive and spread. The infection by A. fumigatus usually occurs in immunocompromised patients due to failed clearance of inhaled conidia. However, the incidence of aspergillosis in immunocompetent hosts has been increasing, the pathogenesis of which is still unknown. Our team previously obtained two clinical nonsporulating A. fumigatus isolates from non-immunocompromised patients, which only have the form of hyphae. This present study demonstrated the in vitro and in vivo characteristics of the two nonsporulating A. fumigatus isolates and verified that their conidiation defects are associated to abolished expression of the sporulation-related central regulatory pathway brlA gene. In addition, we confirmed the mutation site of brlA gene (c.657_660delTCCT) contributes to the nonsporulating phenotype in one clinical isolate. Plate assay showed that the two nonsporulating isolates have a similar resistance to antifungal drugs, cell wall disturbing substances, and oxidative stress compared with the wild-type reference Af293. Most important of all, we employed an immunocompetent mouse model to mimic the pathogenesis of pulmonary aspergillosis in non-immunocompromised patients. It revealed that the hyphae of two nonsporulating isolates and Af293 have similar virulence in immunocompetent hosts. Interestingly, the hyphae fragments of Af293 but not conidia are able to induce invasive aspergillosis in immunocompetent mice. In conclusion, our study indicate that the form of hyphae may play a dominant causative role in pulmonary aspergillosis of immunocompetent hosts rather than conidia.

Alzheimer’s disease (AD) is a serious neurodegenerative disease. While the main pathological characteristic of AD is widely believed to be the accumulation of amyloid-beta (Aβ) in neurons around neurofibrillary plaques, the molecular mechanism of pathological changes is not clear. Traditional Chinese medicine offers many treatments for AD. Among these, Danggui Shaoyao San (DSS) is a classic prescription. In this study, an AD model was established by injecting Aβ 1–42 into the brains of rats, which were then treated with different concentrations of Danggui Shaoyao San (sham operation; model; and Danggui Shaoyao San high-dose, medium-dose, and low-dose intervention groups). The Morris water maze test was used to assess the learning and memory abilities of the animals in each group. Nissl staining was used to detect neurons. Mitophagy was evaluated by transmission electron microscopy and immunofluorescence colocalization. Apoptosis was assessed by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The expression levels of autophagy- and apoptosis-related proteins were measured by western blot. Compared to the model group, the groups of AD rats administered medium and high doses of Danggui Shaoyao San showed significantly increased learning and memory abilities ( P < 0.05 ), as well as significantly increased autophagosomes in the hippocampus. Moreover, the expression of PTEN-induced kinase 1 (PINK1), Parkin, and microtubule-associated protein light chain 3 (LC3-I/LC3-II) was increased, while that of p62 was significantly decreased ( P < 0.05 ). The neuronal apoptosis rate was also significantly decreased, the Bcl-2/Bax ratio was significantly increased, and the cleaved caspase-3 protein expression was significantly decreased ( P < 0.05 ). Therefore, Danggui Shaoyao San inhibited neuronal apoptosis in AD rats via a mechanism that may be related to the activation of the PINK1-Parkin-mediated mitophagy signaling pathway.

The authors aim to present a case study of a three-year professional development program for school leaders with a specific focus on cultivating curriculum leadership. This program is funded by the...

This paper considers the current status of academic performance and administrative leadership of women academics in Taiwan in the context of neo-liberalism. Emergent forces of higher education rest...

In this paper, we study the Dirichlet boundary value problem of a class of nonlinear parabolic equations. By a priori estimates, difference and variation techniques, we establish the existence and uniqueness of weak solutions of this problem.

Aspergillus infections are increasingly recognized as a global health problem because of limited antifungal drugs and occurrence of azole resistance worldwide. More cyp51-mediated and non-cyp51-mediated mechanisms of azole resistance have been identified in clinical and laboratory studies in recent years with applications of molecular biotechnology including next-generation sequencing, reverse genetics and so on. In this review, current research on the molecular mechanisms of azole resistance in A. fumigatus were presented and summarized and meanwhile the putative clinical relevance of these findings from bench work were discussed. Important aims are to gain more insight to mechanism of azole resistance and provide some efficient lead for prevention strategy.

The incidence of aspergillosis continues to rise sharply, while the progress made in expanding the antifungal drug arsenal remains extremely slow, indicating an urgent need for new strategies. Previous studies have shown that the calcium signaling pathway, which is evolutionarily conserved in mammals and fungi, is involved in regulating the tolerance of azoles in fungi. In this study, we performed a preliminary screening among various combinations of different clinical calcium channel blockers and different antifungal drugs. We found that the combination of itraconazole and verapamil showed the best synergistic effect against Aspergillus fumigatus. Thereafter, using the checkboard assays we observed synergistic effects of the combination treatment against most of the A. fumigatus strains tested, including itraconazole-sensitive and itraconazole-resistant strains, with a fractional inhibitory concentration index (FICI) < 0.5. Furthermore, we showed that verapamil strongly decreased the cytosolic calcium transients following itraconazole stimulation by an aequorin-mediated method. Moreover, verapamil influenced the efflux of rhodamine 6G, an azole mimic substance. An ergosterol assay revealed that verapamil alone had no effect on ergosterol biosynthesis, but the combination of itraconazole and verapamil treatment decreased the ergosterol level. Further murine assays were performed using a luciferase-probed bioluminescence imaging method. Drug combination therapy reduced lung burden and improved survival rate. In conclusion, verapamil is a promising candidate to enhance the antifungal activity of itraconazole against A. fumigatus. In addition, our study suggests the effectiveness of an emerging approach based on bioluminescence imaging in monitoring the efficacy of drug combination therapy for invasive aspergillosis.

This research aimed to investigate the key factors of developing effective professional learning communities (PLCs) within the Taiwanese context. Four constructs – supportive and shared leadership, shared visions, collegial trust, and shared practices – were adopted and developed into an instrument for measuring PLC function. A stratified random sampling was conducted with the strata of geographic areas. Out of 335 high schools, 51 schools were chosen and 612 copies of the questionnaires were distributed to teachers. After excluding invalid questionnaires, 444 questionnaires were collected from 34 schools, yielding a response rate of 73%. The final version of the questionnaire had 19 items with a 6-point Likert-type scale. Using confirmative factor analysis, the four factors in the conception of PLCs were confirmed. The results of the structural equation modelling indicated that a collegial trust relationship was strongly and directly related to shared practices, and was an important mediating fac...

With the wide application of Electronic Health Record (EHR) in hospitals in past few decades, researches that employ artificial intelligence (AI) and machine learning methods based on EHR data have been explosive. With such EHR data, one can engage in many tasks such as risk prediction, treatment recommendation, information imputation, etc. The performance of classification or prediction highly depends on the quality of data representation, i.e., representing original records into numerical vectors to facilitate further learning. However, there is little research that focuses on the representation learning techniques for EHR data at present, which makes it hard to understanding the development trend of EHR learning in a global map. In this paper, we bridge this gap by systematically investigating the related research efforts that apply the representation learning on EHR data. We analyze and conclude the techniques used in the typical representation learning approaches as well as the limitations and advantages of them. The survey would provide a comprehensive reference for further analysis and application in EHR research.

This article presents findings of a longitudinal case study conducted at a Taiwanese high school from 2006 to 2010. This school participated in the ‘High Scope Programme’ (HSP), which was sponsored by the Taiwanese National Science Council to promote curricular innovation in science education. Utilising interview data with 11 participating teachers, the study investigated how a team of teachers shared, connected and collaborated to develop a professional learning community (PLC) by establishing a culture of collaboration and collective learning. The HSP team as a PLC evolved through the following four stages: non-initiated stage, initial stage, implementation stage and institutionalisation stage. Three themes emerged from a dynamic system of practice: team-building as an emergent property; individual professional development embedded in collective learning; and collective inquiry for achieving curricular innovation. This study illuminates the evolution of a teacher PLC and provides a nuanced understanding...

Global conceptualization of the professional learning community process: Transitioning from country perspectives to international commonalities Abstract The authors seek to find common PLC structures and actions among global educational systems to enhance understanding and practice. Six international researchers formed the Global Professional Learning Community Network (GloPLCNet), conducted literature reviews of each country’s involvement with PLC actions, and noted similarities and common practices among the school improvement initiatives in five countries. Major constructs were identified, research was conducted (interviews and observations), and themes emerged. A literature review of the constructs led to outcomes. A definition of the Global PLC process, revision of constructs, and further clarification of descriptors were established. External influencing factors were also identified as essential. Finally the awareness that the PLC reculturing effort is guided and influenced by the phases of change w...

Cerebral syphilitic gumma is extremely rare and easily misdiagnosed. We illustrate a case of a cerebral syphilitic gumma developed in just a few months mimicking a brain tumor in a HIV-negative patient and Treponema pallidum was detected in the cerebral syphilitic gumma.

Polysaccharides from mushrooms including Pleurotus eryngii, P. ostreatus, P. nebrodensis, Lentinus edodes, Hypsizygus marmoreus, Flammulina velutipes, Ganoderma lucidum, and Hericium erinaceus were isolated by water extraction and alcohol precipitation. Our results suggest that all tested polysaccharides have the significant antioxidant capacities of scavenging free radicals (1,1-diphenyl-2-picrylhydrazyl and hydroxyl radicals). Among them, the H. erinaceus polysaccharide exhibits the highest 1,1-diphenyl-2-picrylhydrazyl radical-scavenging activity, whereas the L. edodes polysaccharide shows the strongest scavenging ability for hydroxyl radicals. Furthermore, using the MCF-7 breast cancer cell line and HeLa cells, all 8 selected polysaccharides are able to inhibit the proliferation of tumor cells, but the strength of inhibition varied depending on the mushroom species and the concentration used. Notably, G. lucidum polysaccharide shows the highest inhibition activity on MCF-7 cells. By comparison, H. erinaceus polysaccharide has the strongest inhibitory effect on HeLa cells. Moreover, high-performance liquid chromatography with a carbohydrate analysis column showed significant differences in polysaccharide components among these mushrooms. Thus our data suggest that the different species of mushrooms have the variable functions because of their own specific polysaccharide components. The 8 mushroom polysaccharides have the potential to be used as valuable functional food additives or sources of therapeutic agents for antioxidant and cancer treatments, especially polysaccharides from H. erinaceus, L. edodes, and G. lucidum.

The CoFe-based amorphous and Fe-based nanocrystalline alloys possess excellent soft magnetic properties due to their nearly zero-magnetostriction and very low magnetic anisotropy. So they are good candidate materials for power electronics and giant magneto-impedance (GMI) sensor applications. As an indication of their AC performance, energy losses were determined by the measurements of impedance for Co68.2Fe4.3Si12.5B15 amorphous wire and Fe73.5Cu1Nb3Si13.5B9 nanocrystalline wires with different domain structure. The measurements were carried out at a frequency range of 10 – 104 Hz and induction amplitudes of 0.1 – 1.2 T. Although the measured results show good agreement with the scale theory model of energy loss, different origins of energy loss in the investigated samples have been concluded by comparing the experimental data with the Bertotti’s statistical model. The differences of energy loss in these samples could be explained by considering the magnetic structure and circular technical magnetization processes.

The rapid and global emergence of azole resistance in the human pathogen Aspergillus fumigatus has drawn attention. Thus, a thorough understanding of its mechanisms of drug resistance requires extensive exploration. In this study, we found that the loss of the putative calcium-dependent protein-encoding gene algA causes an increased frequency of azole-resistant A. fumigatus isolates. In contrast to previously identified azole-resistant isolates related to cyp51A mutations, only one isolate carries a point mutation in cyp51A (F219L mutation) among 105 independent stable azole-resistant isolates. Through next-generation sequencing (NGS), we successfully identified a new mutation (R243Q substitution) conferring azole resistance in the putative A. fumigatus farnesyltransferase Cox10 (AfCox10) (AFUB_065450). High-performance liquid chromatography (HPLC) analysis verified that the decreased absorption of itraconazole in related Afcox10 mutants is the primary reason for itraconazole resistance. Moreover, a complementation experiment by reengineering the mutation in a parental wild-type background strain demonstrated that both the F219L and R243Q mutations contribute to itraconazole resistance in an algA -independent manner. These data collectively suggest that the loss of algA results in an increased frequency of azole-resistant isolates with a non- cyp51A mutation. Our findings indicate that there are many unexplored non- cyp51A mutations conferring azole resistance in A. fumigatus and that algA defects make it possible to isolate drug-resistant alleles. In addition, our study suggests that genome-wide sequencing combined with alignment comparison analysis is an efficient approach to identify the contribution of single nucleotide polymorphism (SNP) diversity to drug resistance.

Pericentrin is a large coiled-coil protein in mammalian centrosomes that serves as a multifunctional scaffold for anchoring numerous proteins. Recent studies have linked numerous human disorders with mutated or elevated levels of pericentrin, suggesting unrecognized contributions of pericentrin-related proteins to the development of these disorders. In this study, we characterized AnPcpA, a putative homolog of pericentrin-related protein in the model filamentous fungus Aspergillus nidulans , and found that it is essential for conidial germination and hyphal development. Compared to the hyphal apex localization pattern of calmodulin (CaM), which has been identified as an interactive partner of the pericentrin homolog, GFP-AnPcpA fluorescence dots are associated mainly with nuclei, while the accumulation of CaM at the hyphal apex depends on the function of AnPcpA. In addition, the depletion of AnPcpA by an inducible alcA promoter repression results in severe growth defects and abnormal nuclear segregation. Most interestingly, in mature hyphal cells, knockdown of pericentrin was able to significantly induce changes in cell shape and cytoskeletal remodeling; it resulted in some enlarged compartments with condensed nuclei and anucleate small compartments as well. Moreover, defects in AnPcpA significantly disrupted the microtubule organization and nucleation, suggesting that AnPcpA may affect nucleus positioning by influencing microtubule organization.

This paper explores the interplay between identity reconstruction of indigenous college students and the effects of transformative learning on their self-development and collective action. Seventeen indigenous college students were interviewed for this study. The findings showed that most indigenous college students developed stigmatized identity and low self-esteem before entering college. Participating in native student clubs and a non-formal tribal service program empowered students to raise their ethnic consciousness. The study also found that transformative learning of college students affected development of their positive self-concepts, interpersonal relationships, and ethnic and cultural identities. The effects of perceptive transformation also empowered meaningful connections in these students to personal career choices and sustainability of ethnic groups and cultural development.

Throughout the world, rapid political and economic change has applied enormous pressure on educators addressing leadership and accountability measures to improve instructional practices and student performance. Decentralisation of central authority regarding school site-based decision-making has drastically changed the educational environment in which the duties of school administration have become much more demanding. This paper, in reviewing reform initiatives and school leadership research in Taiwan, introduces first the background of Taiwanese educational reform, then discusses the challenges and dilemmas that school leaders typically face. New leadership practices, such as instructional leadership and teacher leadership, are developed to respond to the needs of educational reform. Finally, this paper analyses the literature of school leadership research in Taiwan, having discovered that quantitative methods have predominated; in addition, a gap exists between leadership practices and academic studies...