Antifungal Activity of the Dichloromethane Extract of CaoHuangGuiXiang Formula Against Candida auris by in vitro and in vivo Evaluation.

Purpose: CaoHuangGuiXiang (CHGX) formula is a traditional Chinese medicine for the treatment of Candida-related infection. However, its antifungal mechanisms against the emerging fungal pathogen Candida auris remain unclear. This study aimed to evaluate the antifungal activity of the dichloromethane extract of CHGX (CHGX-DME) and clarified its antifungal mechanims against C. auris. Methods: The major components of CHGX-DME were identified by ultra-performance liquid chromatography tandem mass spectrometry. Then, the minimal inhibitory concentration (MIC) assay and the time-kill kinetic assay were performed to investigate the in vitro antifungal activity of CHGX-DME against C. auris, including 8 isolates of 4 discrete clades and 2 special phenotypes (filamentous and aggregative). Furthermore, the effect of CHGX-DME on biofilm development was examined. In addition, the in vivo toxicity and efficacy of CHGX-DME were evaluated in a Galleria mellonella infection model. Results: First, 20 major compounds in CHGX-DME were detected and characterized. The MIC50% and MIC90% of CHGX-DME against C. auris isolates ranged from 50-200 mg/L and 100-400 mg/L, respectively. At 400 mg/L, CHGX-DME was able to efficiently kill more than 70% and 90% of C. auris cells after 3 hours and 6 hours of treatment, respectively. This notable antifungal activity exhibited a dosage- and time-dependent manner. Moreover, CHGX-DME not only played a critical role in inhibiting the proliferation of filamentous and aggregative cells, but also showed restricting effect on biofilm development in C. auris. Importantly, it significantly improved the survival rate and reduced the fungal burden in G. mellonella infection models, suggesting a remarkable treatment effect against C. auris infection. Conclusion: CHGX-DME exhibited potent antifungal activity against C. auris and significantly ameliorated this fungal infection in the G. mellonella model, confirming that it would be a promising antifungal drug for the troublesome and emerging fungal pathogen C. auris.

Extracellular components in enteroaggregative Escherichia coli biofilm and impact of treatment with proteinase K, DNase or sodium metaperiodate.

Enteroaggregative E. coli (EAEC) is a major cause of diarrhea worldwide. EAEC are highly adherent to cultured epithelial cells and make biofilms. Both adherence and biofilm formation rely on the presence of aggregative adherence fimbriae (AAF). We compared biofilm formation from two EAEC strains of each of the five AAF types. We found that AAF type did not correlate with the level of biofilm produced. Because the composition of the EAEC biofilm has not been fully described, we stained EAEC biofilms to determine if they contained protein, carbohydrate glycoproteins, and/or eDNA and found that EAEC biofilms contained all three extracellular components. Next, we assessed the changes to the growing or mature EAEC biofilm mediated by treatment with proteinase K, DNase, or a carbohydrate cleavage agent to target the different components of the matrix. Growing biofilms treated with proteinase K had decreased biofilm staining for more than half of the strains tested. In contrast, although sodium metaperiodate only altered the biofilm in a quantitative way for two strains, images of biofilms treated with sodium metaperiodate showed that the EAEC were more spread out. Overall, we found variability in the response of the EAEC strains to the treatments, with no one treatment producing a biofilm change for all strains. Finally, once formed, mature EAEC biofilms were more resistant to treatment than biofilms grown in the presence of those same treatments.

Association of Putative Virulence Genes with HEp-2 Cell Adherence and Biofilm Production in Enteroaggregative E. coli Strains Isolated from Acute Diarrheal and Healthy Children, India.

Enteroaggregative Escherichia coli (EAEC) is an emerging enteric pathogen that causes acute and chronic diarrhea in developed and industrialized countries in children. EAEC colonizes the human intestine and this ability to form colonies and biofilm is an important step in pathogenesis. Here, we investigated the relationship between known or putative 22 EAEC virulence genes and biofilm formation in isolates derived from acute diarrhea and healthy children and their aggregative adherence (AA) pattern with Hep-2 cell lines. A total of 138 EAEC isolates were recovered from 1210 stool samples from children (age < 10 years) suffering from acute diarrhea and 33 EAEC strains isolated from 550 healthy children (control group) of different Anganwadi centers in Chandigarh region were included. Polymerase chain reaction using the primer pair pCVD432 identified E. coli isolates as EAEC. A total of 22 virulence-related genes have been identified using M-PCR chain reactions. The crystal violet method was used for the quantitative biofilm assay. Aggregative adherence assay was also studied using HEp-2 cell lines. Of 138 EAEC isolates from the acute diarrheal group, 121 (87.6%) EAEC isolates produced biofilm. In our findings, typical EAEC (62%) isolates were strong biofilm producers (37.5%) in the diarrheal group. Among adhesive variants, agg4A (39.6%) and aggA (21.6%) were the most common and were statistically significant (p = 0.01 and p = 0.03 respectively). We reported that the aggR gene along with the typical AA pattern was present in 71.4% of the EAEC strains in the diarrheal group, whereas it was present in 44% of the control group. Other aggR non-dependent genes like ORF3 and eilA may also lead to biofilm formation. In conclusion, there is significant heterogeneity in putative virulence genes of EAEC isolates from children and biofilm formation is associated with the combination of many genes.

Anti-Aggregative and Protective Effects of Vicenin-2 on Heat and Oxidative Stress-Induced Damage on Protein Structures.

Vicenin-2, a flavonoid categorized as a flavones subclass, exhibits a distinctive and uncommon C-glycosidic linkage. Emerging evidence challenges the notion that deglycosylation is not a prerequisite for the absorption of C-glycosyl flavonoid in the small intestine. Capitalizing on this experimental insight and considering its biological attributes, we conducted different assays to test the anti-aggregative and antioxidant capabilities of vicenin-2 on human serum albumin under stressful conditions. Within the concentration range of 0.1-25.0 µM, vicenin-2 effectively thwarted the heat-induced HSA fibrillation and aggregation of HSA. Furthermore, in this study, we have observed that vicenin-2 demonstrated protective effects against superoxide anion and hydroxyl radicals, but it did not provide defense against active chlorine. To elucidate the underlying mechanisms, behind this biological activity, various spectroscopy techniques were employed. UV-visible spectroscopy revealed an interaction between HSA and vicenin-2. This interaction involves the cinnamoyl system found in vicenin-2, with a peak of absorbance observed at around 338 nm. Further evidence of the interaction comes from circular dichroism spectrum, which shows that the formation of bimolecular complex causes a reduction in α-helix structures. Fluorescence and displacement investigations indicated modifications near Trp214, identifying Sudlow's site I, similarly to the primary binding site. Molecular modeling revealed that vicenin-2, in nonplanar conformation, generated hydrophobic interactions, Pi-pi stacking, and hydrogen bonds inside Sudlow's site I. These findings expand our understanding of how flavonoids bind to HSA, demonstrating the potential of the complex to counteract fibrillation and oxidative stress.

Parallel evolution of the G protein-coupled receptor GrlG and the loss of fruiting body formation in the social amoeba Dictyostelium discoideum evolved under low relatedness.

Aggregative multicellularity relies on cooperation among formerly independent cells to form a multicellular body. Previous work with Dictyostelium discoideum showed that experimental evolution under low relatedness profoundly decreased cooperation, as indicated by the loss of fruiting body formation in many clones and an increase of cheaters that contribute proportionally more to spores than to the dead stalk. Using whole-genome sequencing and variant analysis of these lines, we identified 38 single nucleotide polymorphisms in 29 genes. Each gene had 1 variant except for grlG (encoding a G protein-coupled receptor), which had 10 unique SNPs and 5 structural variants. Variants in the 5' half of grlG-the region encoding the signal peptide and the extracellular binding domain-were significantly associated with the loss of fruiting body formation; the association was not significant in the 3' half of the gene. These results suggest that the loss of grlG was adaptive under low relatedness and that at least the 5' half of the gene is important for cooperation and multicellular development. This is surprising given some previous evidence that grlG encodes a folate receptor involved in predation, which occurs only during the single-celled stage. However, non-fruiting mutants showed little increase in a parallel evolution experiment where the multicellular stage was prevented from happening. This shows that non-fruiting mutants are not generally selected by any predation advantage but rather by something-likely cheating-during the multicellular stage.

Decision-making in nursing research and practice-Application of the Cognitive Continuum Theory: A meta-aggregative systematic review.

AIM: To explore how the Cognitive Continuum Theory has been used in qualitative nursing research and to what extent it has been integrated in the research process using the Qualitative Network for Theory Use and Methodology (QUANTUM). BACKGROUND: Theory, research and nursing are intrinsically linked, as are decision-making and nursing practice. With increasing pressure on nurses to improve patient outcomes, systematic knowledge regarding decision-making is critical and urgent. DESIGN: A meta-aggregative systematic review. METHODS: DATABASES: CINAHL, Medline, PsycINFO, Embase and PubMed were searched from inception until May 2022 for peer-reviewed research published in English. Seven studies were included and assessed for methodological quality using the Joanna Briggs Institute checklist for qualitative research. A meta-aggregative synthesis was conducted using Joanna Briggs methodology. The QUANTUM typology was used to evaluate the visibility of the Cognitive Continuum Theory in the research process. RESULTS: The review identified five synthesised findings, namely: 1. the decision-making capacity of the individual nurse, 2. nurses' level of experience, 3. availability of decision support tools, 4. the availability of resources and 5. access to senior staff and peers. Only two of seven studies rigorously applied the theory. The included studies were mainly descriptive-exploratory in nature. CONCLUSION: The transferability of the Cognitive Continuum Theory was demonstrated; however, evolution or critique was absent. A gap in the provision of a patient-centric approach to decision-making was identified. Education, support and research is needed to assist decision-making. A new Person-Centred Nursing Model of the Cognitive Continuum Theory has been proposed to guide future research in clinical decision-making. RELEVANCE TO CLINICAL PRACTICE: Nurses make numerous decisions every day that directly impact patient care, therefore development and testing of new theories, modification and revision of older theories to reflect advances in knowledge and technology in contemporary health care are essential.

A Mini-Review of Enteroaggregative Escherichia coli with a Specific Target on the Virulence Factors Controlled by the AggR Master Regulator.

Enteroaggregative Escherichia coli (EAEC) strains have been linked to several outbreaks of severe diarrhea around the world, and this bacterium is now commonly resistant to antibiotics. As part of the pathophysiology of EAEC, the characteristic pattern of adherence looks like stacked bricks on the intestinal epithelium. This phenotype depends on an aggregative adhesion plasmid (pAA), which codes for a regulatory protein named AggR. The AggR protein is a master regulator that transcriptionally actives the main virulence genes in this E. coli pathotype, such as those that encode the aggregative adhesion fimbriae, dispersin and its secretion apparatus, Aar regulatory protein, and type VI secretion system. Several reports have shown that AggR positively affects most EAEC virulence genes, functioning as a classic transcriptional activator in the promoter region of these genes, interacting with the RNA polymerase. This minireview article integrates the information about virulence determinants of EAEC controlled by the AggR regulator.

Diversity of 'simple' multicellular eukaryotes: 45 independent cases and six types of multicellularity.

Multicellularity evolved multiple times in the history of life, with most reviewers agreeing that it appeared at least 20 times in eukaryotes. However, a specific list of multicellular eukaryotes with clear criteria for inclusion has not yet been published. Herein, an updated critical review of eukaryotic multicellularity is presented, based on current understanding of eukaryotic phylogeny and new discoveries in microbiology, phycology and mycology. As a result, 45 independent multicellular lineages are identified that fall into six distinct types. Functional criteria, as distinct from a purely topological definition of a cell, are introduced to bring uniformity and clarity to the existing definitions of terms such as colony, multicellularity, thallus or plasmodium. The category of clonal multicellularity is expanded to include: (i) septated multinucleated thalli found in Pseudofungi and early-branching Fungi such as Chytridiomycota and Blastocladiomycota; and (ii) multicellular reproductive structures formed by plasmotomy in intracellular parasites such as Phytomyxea. Furthermore, (iii) endogeneous budding, as found in Paramyxida, is described as a form of multicellularity. The best-known case of clonal multicellularity, i.e. (iv) non-separation of cells after cell division, as known from Metazoa and Ochrophyta, is also discussed. The category of aggregative multicellularity is expanded to include not only (v) pseudoplasmodial forms, such a sorocarp-forming Acrasida, but also (vi) meroplasmodial organisms, such as members of Variosea or Filoreta. A common set of topological, geometric, genetic and life-cycle criteria are presented that form a coherent, philosophically sound framework for discussing multicellularity. A possibility of a seventh type of multicellularity is discussed, that of multi-species superorganisms formed by protists with obligatory bacterial symbionts, such as some members of Oxymonada or Parabasalia. Its inclusion is dependent on the philosophical stance taken towards the concepts of individuality and organism in biology. Taxa that merit special attention are identified, such as colonial Centrohelea, and a new speculative form of multicellularity, possibly present in some reticulopodial amoebae, is briefly described. Because of insufficient phylogenetic and morphological data, not all lineages could be unequivocally identified, and the true total number of all multicellular eukaryotic lineages is therefore higher, likely close to a hundred.

The Anti-Aggregative Potential of Resolvin E1 on Human Platelets.

Resolvin E1 is a metabolite of eicosapentaenoic acid (EPA) which is one of the omega-3 polyunsaturated fatty acids (omega-3 PUFAs). The antiplatelet properties of omega-3 PUFAs are well known, but the effect of resolvin E1 on platelets via the collagen receptors is extremely poorly reported. We investigated the effect of resolvin E1 on collagen-induced platelet aggregation, activation, and reactivity, and also platelet membrane fluidity. The ultimate and statistically significant results showed that resolvin E1 may inhibit platelet reactivity due to the reduction of collagen-induced platelet aggregation in platelet-rich plasma and isolated platelets, but not in whole blood. Also, resolvin E1 significantly reduced P-selectin exposure on collagen-stimulated platelets. Moreover, we demonstrated that resolvin E1 can maintain platelet membrane structure (without increasing membrane fluidity). The association between platelet reactivity and membrane fluidity, including resolvin E1 and collagen receptors requires further research. However, the goal of this study was to shed light on the molecular mechanisms behind the anti-aggregative effects of resolvin E1 on platelets, which are still not fully clarified. We also indicate an innovative research direction focused on further analysis and then use of omega-3 PUFAs metabolites as antiplatelet compounds for future applications in the treatment and prevention of cardiovascular diseases.

Regional Well-Being Disparities in Morocco and its OECD Partners.

This article proposes a multidimensional analysis grid to assess regional disparities, transcending monetary considerations. This grid agrees overall with the common framework that prevails in the literature review that we have carried out. It is built around four dimensions of well-being: economy (development, labor market, human capital and innovation), social (health, living conditions and gender), environment and governance. Our analysis of regional disparities was based on the synthesis of fifteen indicators by constructing a Synthetic Index of Well-being (SIWB) by combining its four dimensions using an aggregative-compensative approach. This analysis covers Morocco, 35 of the OECD member countries and their 389 regions between 2000 and 2019. We have assessed the dynamics of Moroccan regions compared to those of the benchmark. Thus, we have highlighted the gaps to be made up in relation to the different areas of well-being as well as their thematic variations.