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Pulmonary mucormycosis is a rare and lethal fungal infection elicited by fungi of the order Mucorales. The disease predominantly affects immunocompromised hosts, like those with diabetes mellitus, hematologic malignancies, or those undergoing immunosuppressive therapy. We, at this moment, report a case of pulmonary mucormycosis in a 55-year-old gentleman, exemplifying the ferocity of clinical disease, diagnostic dilemmas, and rapidity of progression. A diagnosis of pulmonary mucormycosis was based on diagnostic imaging and flexible bronchoscopy. Despite aggressive antifungal and supportive treatment, the patient's condition deteriorated further, and unfortunately succumbed to cardiorespiratory arrest. This case reinforces the importance of early recognition of pulmonary mucormycosis and aggressive medical management, especially in immunocompromised patients, in salvaging lives with good outcomes and preventing the fulminant progression of the disease process.
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Eukaryotic organisms are composed of different cell types with defined shapes and functions. Specific cell types are produced by the process of cell differentiation, which is regulated by signal transduction pathways. Signaling pathways regulate cell differentiation by sensing cues and controlling the expression of target genes whose products generate cell types with specific attributes. In studying how cells differentiate, fungi have proved valuable models because of their ease of genetic manipulation and striking cell morphologies. Many fungal species undergo filamentous growth-a specialized growth pattern where cells produce elongated tube-like projections. Filamentous growth promotes expansion into new environments, including invasion into plant and animal hosts by fungal pathogens. The same signaling pathways that regulate filamentous growth in fungi also control cell differentiation throughout eukaryotes and include highly conserved mitogen-activated protein kinase (MAPK) pathways, which is the focus of this review. In many fungal species, mucin-type sensors regulate MAPK pathways to control filamentous growth in response to diverse stimuli. Once activated, MAPK pathways reorganize cell polarity, induce changes in cell adhesion, and promote the secretion of degradative enzymes that mediate access to new environments. However, MAPK pathway regulation is complicated because related pathways can share components with each other yet induce unique responses (i.e. signal specificity). In addition, MAPK pathways function in highly integrated networks with other regulatory pathways (i.e. signal integration). Here, we discuss signal specificity and integration in several yeast models (mainly Saccharomyces cerevisiae and Candida albicans) by focusing on the filamentation MAPK pathway. Because of the strong evolutionary ties between species, a deeper understanding of the regulation of filamentous growth in established models and increasingly diverse fungal species can reveal fundamentally new mechanisms underlying eukaryotic cell differentiation.
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The role of model organisms such as yeasts in life science research is crucial. Although the baker's yeast (Saccharomyces cerevisiae) is the most popular model among yeasts, the contribution of the fission yeasts (Schizosaccharomyces) to life science is also indisputable. Since both types of yeasts share several thousands of common orthologous genes with humans, they provide a simple research platform to investigate many fundamental molecular mechanisms and functions, thereby contributing to the understanding of the background of human diseases. In this review, we would like to highlight the many advantages of fission yeasts over budding yeasts. The usefulness of fission yeasts in virus research is shown as an example, presenting the most important research results related to the Human Immunodeficiency Virus Type 1 (HIV-1) Vpr protein. Besides, the potential role of fission yeasts in the study of prion biology is also discussed. Furthermore, we are keen to promote the uprising model yeast Schizosaccharomyces japonicus, which is a dimorphic species in the fission yeast genus. We propose the hyphal growth of S. japonicus as an unusual opportunity as a model to study the invadopodia of human cancer cells since the two seemingly different cell types can be compared along fundamental features. Here we also collect the latest laboratory protocols and bioinformatics tools for the fission yeasts to highlight the many possibilities available to the research community. In addition, we present several limiting factors that everyone should be aware of when working with yeast models.
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Southern root-knot nematode (Meloidogyne incognita) and Fusarium wilt fungus (Fusarium oxysporum) are one of the most predominant pathogens responsible for substantial agricultural yield reduction of tomato. The current study planned to assess the effects of M. incognita (Mi) and F. oxysporum (Fo) and their co-infection on two tomato cultivars, Zhongza 09 (ZZ09) and Gailing Maofen 802 (GLM802). The present study examined the effects of co-infection on leaf morphology, chlorophyll content, leaf area, and histopathology. The present study used metabolomics to evaluate plant-pathogen interactions. The outcomes of the current study revealed that chlorophyll content and leaf area decreased more in GLM802 during co-infection. In co-infection (Fo + Mi), the chlorophyll content reduction in ZZ09 was 11%, while in GLM802 the reduction reached up to 31% as compared to control. Moreover, the reduction in leaf are in ZZ09 was 31%, however, in the GLM802 reduction was observed 54% as compared to control plants. Similarly, GLM802 stems exhibited larger brown patches on their vascular bundles than ZZ09 stems. The rate of browning of GLM802 stems was 247% more than ZZ09, during co-infection. Moreover, GLM802 roots exhibited a higher abundance of hyphae and larger galls than ZZ09 roots. In metabolic studies, glutathione, succinic acid, and 2-isopropylmalic acid decreased, whereas spermine and fumaric acid increased in GLM802 co-infected stems. It indicates that GLM802 is weakly resistant; therefore, F. oxysporum and other pathogens readily damage tissue. In the co-infected stem of ZZ09, L-asparagine and shikimic acid increased, but pipecolic acid, L-saccharine, and 2-isopropylmalic acid declined. L-asparagine was crucial in preserving the stability of nitrogen metabolism, chlorophyll synthesis, and leaf growth in ZZ09. Shikimic acid's substantial accumulation could explain the limited extent of browning observed in the vascular bundles of ZZ09. Thus, the present study provides insight into M. incognita and F. oxysporum co-infection in two tomato cultivars, which may aid breeding efforts to generate commercially viable resistant cultivars. However, further research on the relationship between M. incognita and F. oxysporum in different host plants is required in the future.
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Effective management of microbial biofilms holds significance within food and medical environments. Candida albicans, an opportunistic fungus, forms mucosal biofilms closely linked to candidiasis and drug-resistant infections due to their drug tolerance. Morphologic change from yeast to filamentous cells is a key virulence factor and a prerequisite for biofilm development. This study investigated the anti-fungal and antibiofilm activities of 20 flavonoids against C. albicans. With their known antioxidant capabilities, flavonoids hold promise in combating infections associated with biofilms. Among them, flavone and its derivatives exhibited moderate antifungal activity, 3,2'-dihydroxyflavone (3,2'-DHF) at 1 µg/mL exhibited strong antibiofilm activity (MIC 50 µg/mL). In addition, 3,2'-DHF dramatically inhibited cell aggregation and germ tube/hyphae formation. Transcriptomic analyses revealed that flavone and 3,2'-DHF behaved differently, as 3,2'-DHF downregulated the expressions of germ tube/hyphae-forming and biofilm-related genes (ECE1, HWP1, TEC1, and UME6) but upregulated the biofilm/hyphal regulators (CHK1, IFD6, UCF1, and YWP1). Tests evaluating toxicity with plant and nematode models revealed that flavone and 3,2'-DHF exhibited mild toxicity. Current results indicate that hydroxylated flavone derivatives can enhance anti-fungal and antibiofilm activities and provide a source of potential anti-fungal agents against drug-resistant C. albicans.
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Onychomycosis (OM) is a widespread infection requiring prolonged treatment with potential side effects. Diagnostic certainty is therefore essential before initiating antifungal therapy. Molecular biology has already shown benefits in reducing the time to diagnosis, providing technical ease, and increasing sensitivity for the respective species that molecular tests can detect. Nevertheless, causative agents are numerous, and culture remains essential, particularly for detecting non-dermatophytes mold infections. This study compared the performance of three different diagnostic strategies: conventional culture technique, the multiplex DermaGenius® 2.0 PCR (DG), and a mixed PCR/culture algorithm guided by the result of direct examination with calcofluor (DEC). The mixed algorithm (MA) prioritizes DG PCR and DEC as the primary diagnostic tools, supplemented by selective sample inoculation when mycelial elements are visualized in DEC and when DG PCR fails to detect any fungus or identifies a fungus with morphology differing from that observed in DEC (filamentous fungi versus yeasts). With only 13% of samples requiring inoculation, MA emerged as the most effective strategy, demonstrating significantly higher sensitivity (98.18%; p < 0.001) compared to single-method approaches (78.18% for DG PCR alone and 74.55% for culture alone) while maintaining a specificity comparable to DG PCR (100%). This new approach saves time in result delivery, requires fewer human resources, and increases diagnostic accuracy to better meet the needs of clinicians.
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The ability of Candida albicans to switch its morphology from yeast to filaments, known as polymorphism, may bias the methods used in microbial quantification. Here, we compared the quantification methods [cell/mL, colony forming units (CFU)/mL, and the number of nuclei estimated by viability polymerase chain reaction (vPCR)] of three strains of C. albicans (one reference strain and two clinical isolates) grown as yeast, filaments, and biofilms. Metabolic activity (XTT assay) was also used for biofilms. Comparisons between the methods were evaluated by agreement analyses [Intraclass and Concordance Correlation Coefficients (ICC and CCC, respectively) and Bland-Altman Plot] and Pearson Correlation (α = 0.05). Principal Component Analysis (PCA) was employed to visualize the similarities and differences between the methods. Results demonstrated a lack of agreement between all methods irrespective of fungal morphology/growth, even when a strong correlation was observed. Bland-Altman plot also demonstrated proportional bias between all methods for all morphologies/growth, except between CFU/mL X vPCR for yeasts and biofilms. For all morphologies, the correlation between the methods were strong, but without linear relationship between them, except for yeast where vPCR showed weak correlation with cells/mL and CFU/mL. XTT moderately correlated with CFU/mL and vPCR and weakly correlated with cells/mL. For all morphologies/growth, PCA showed that CFU/mL was similar to cells/mL and vPCR was distinct from them, but for biofilms vPCR became more similar to CFU/mL and cells/mL while XTT was the most distinct method. As conclusions, our investigation demonstrated that CFU/mL underestimated cells/mL, while vPCR overestimated both cells/mL and CFU/mL, and that the methods had poor agreement and lack of linear relationship, irrespective of C. albicans morphology/growth.1.
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The antagonistic interplay between phosphorus (P) and zinc (Zn) in plants is well established. However, the molecular mechanisms mediating those interactions as influenced by arbuscular mycorrhizal (AM) symbiosis remain unclear. We investigated Zn concentrations, root AM symbiosis, and transcriptome profiles of maize roots grown under field conditions upon different P levels. We also validated genotype-dependent P-Zn uptake in selected genotypes from a MAGIC population and conducted mycorrhizal inoculation experiments using mycorrhizal-defective mutant pht1;6 to elucidate the significance of AM symbiosis in P-Zn antagonism. Finally, we assessed how P supply affects Zn transporters and Zn uptake in extraradical hyphae within a three-compartment system. Elevated P levels led to a significant reduction in maize Zn concentration across the population, correlating with a marked decline in AM symbiosis, thus elucidating the P-Zn antagonism. We also identified ZmPht1;6 is crucial for AM symbiosis and confirmed that P-Zn antagonistic uptake is dependent on AM symbiosis. Moreover, we found that high P suppressed the expression of the fungal RiZRT1 and RiZnT1 genes, potentially impacting hyphal Zn uptake. We conclude that high P exerts systemic regulation over root and AM hyphae-mediated Zn uptake in maize. These findings hold implications for breeding Zn deficiency-tolerant maize varieties.
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Regulação da Expressão Gênica de Plantas , Micorrizas , Fósforo , Solo , Simbiose , Zea mays , Zinco , Zea mays/microbiologia , Zea mays/metabolismo , Zea mays/genética , Micorrizas/fisiologia , Zinco/metabolismo , Fósforo/metabolismo , Solo/química , Transporte Biológico , Raízes de Plantas/microbiologia , Raízes de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Hifas , Genótipo , Mutação/genéticaRESUMO
Candida species comprise a ubiquitous pathogenic fungal genus responsible for causing candidiasis. They are one of the primary causatives of several mucosal and systemic infections in humans and can survive in various environments. In this study, we investigated the antifungal, anti-biofilm, and anti-hyphal effects of six N-substituted phthalimides against three Candida species. Of the derivatives, N-butylphthalimide (NBP) was the most potent, with a minimum inhibitory concentration (MIC) of 100 µg/ml and which dose-dependently inhibited biofilm at sub-inhibitory concentrations (10-50 µg/ml) in both the fluconazole-resistant and fluconazole-sensitive Candida albicans and Candida parapsilosis. NBP also effectively inhibited biofilm formation in other pathogens including uropathogenic Escherichia coli, Staphylococcus epidermidis, Staphylococcus aureus, and Vibrio parahaemolyticus, along with the polymicrobial biofilms of S. epidermidis and C. albicans. NBP markedly inhibited the hyphal formation and cell aggregation of C. albicans and altered its colony morphology in a dose-dependent manner. Gene expression analysis showed that NBP significantly downregulated the expression of important hyphal- and biofilm-associated genes, i.e., ECE1, HWP1, and UME6, upon treatment. NBP also exhibited mild toxicity at concentrations ranging from 2 to 20 µg/ml in a nematode model. Therefore, this study suggests that NBP has anti-biofilm and antifungal potential against various Candida strains.
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Antifúngicos , Biofilmes , Candida albicans , Hifas , Testes de Sensibilidade Microbiana , Ftalimidas , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Antifúngicos/farmacologia , Ftalimidas/farmacologia , Candida albicans/efeitos dos fármacos , Hifas/efeitos dos fármacos , Hifas/crescimento & desenvolvimento , Candida/efeitos dos fármacos , Candidíase/microbiologia , Candidíase/tratamento farmacológico , Animais , Humanos , Candida parapsilosis/efeitos dos fármacos , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fluconazol/farmacologiaRESUMO
AIM: Isolation, identification, structural and functional characterization of potent anti-Candida compound with specific antagonistic activities against significant human pathogens, Candida albicans and C. auris. METHODS AND RESULTS: The compound (55B3) was purified from the metabolites produced by Streptomyces chrestomyceticus ADP4 by employing column chromatography. The structure of 55B3 was determined from the analyses of spectral data that included LCMS, nuclear magnetic resonance, FTIR, and UV spectroscopies. It was identified as a novel derivative of diterpenic aromatic acid, 3-(dictyotin-11'-oate-15'α, 19'ß-olide)-4-(dictyotin-11'-oate-15â³α, 19â³ß-olide)-protocatechoic acid. The compound displayed potent antifungal and anti-biofilm activities against C. albicans ATCC 10231 (Minimum Inhibitory Concentration, MIC90:14.94 ± 0.17 µgmL-1 and MBIC90: 16.03 ± 1.1 µgmL-1) and against C. auris CBS 12372 (MIC90: 21.75 ± 1.5 µgmL-1 and Minimum Biofilm Inhibitory Concentration, MBIC90: 18.38 ± 1.78 µgmL-1). Further, pronounced inhibition of important virulence attributes of Candida spp., e.g. yeast-to-hyphae transition, secretory aspartyl proteinase and phospholipase B by 55B3 was noted at subinhibitory concentrations. A plausible mechanism of anti-Candida action of the compound appeared to be the inhibition of ergosterol biosynthesis, which was inhibited by 64 ± 3% at the MIC90 value. The non-cytotoxic attribute of the compound was noted in the liver cell line (HepG2 cells). CONCLUSION: The present work led to the discovery of a novel diterpenic derivative produced by S. chrestomyceticus ADP4. The compound displayed potent anti-Candida activity, particularly against the two most significant human pathogens, C. albicans and C. auris, which underlined its significance as a potential drug candidate for infections involving these pathogens.
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Antifúngicos , Biofilmes , Candida albicans , Testes de Sensibilidade Microbiana , Streptomyces , Fatores de Virulência , Biofilmes/efeitos dos fármacos , Streptomyces/metabolismo , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Humanos , Candida/efeitos dos fármacosRESUMO
Candida albicans is an opportunistic fungal pathogen that can switch between yeast and hyphal morphologies depending on the environmental cues it receives. The switch to hyphal form is crucial for the establishment of invasive infections. The hyphal form is also characterized by the cell surface expression of hyphae-specific proteins, many of which are GPI-anchored and important determinants of its virulence. The coordination between hyphal morphogenesis and the expression of GPI-anchored proteins is made possible by an interesting cross-talk between GPI biosynthesis and the cAMP-PKA signaling cascade in the fungus; a parallel interaction is not found in its human host. On the other hand, in the nonpathogenic yeast, Saccharomyces cerevisiae, GPI biosynthesis is shut down when filamentation is activated and vice versa. This too is achieved by a cross-talk between GPI biosynthesis and cAMP-PKA signaling. How are diametrically opposite effects obtained from the cross-talk between two reasonably well-conserved pathways present ubiquitously across eukarya? This Review attempts to provide a model to explain these differences. In order to do so, it first provides an overview of the two pathways for the interested reader, highlighting the similarities and differences that are observed in C. albicans versus the well-studied S. cerevisiae model, before going on to explain how the different mechanisms of regulation are effected. While commonalities enable the development of generalized theories, it is hoped that a more nuanced approach, that takes into consideration species-specific differences, will enable organism-specific understanding of these processes and contribute to the development of targeted therapies.
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Candida albicans , Proteínas Quinases Dependentes de AMP Cíclico , AMP Cíclico , Hifas , Saccharomyces cerevisiae , Transdução de Sinais , Candida albicans/metabolismo , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Hifas/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Glicosilfosfatidilinositóis/metabolismo , Glicosilfosfatidilinositóis/biossíntese , Humanos , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genéticaRESUMO
BACKGROUND: Basidiobolomycosis is a rare fungal infection caused by Basidiobolus ranarum. CASE PRESENTATION: A 53-year-old man from Saudi Arabia with a known history of diverticulosis presented with severe abdominal pain and diarrhea. A CT scan revealed circumferential wall thickening of the descending and sigmoid colon with surrounding fat stranding, suggesting a diagnosis of complicated diverticulitis. Additional thick fluid was observed around the affected area. Surgical excision was pursued. A gross examination of two received large bowel segments disclosed marked ulcerated mucosa and wall thickening with exudate-covered serosal surfaces and adhesions. Microscopic examination unveiled significant infiltration by eosinophils, polymorphonuclear leukocytes, and granulomatous inflammation. Thin-walled, broad fungal hyphae of Basidiobolus, surrounded by eosinophilic material, were identified. Granulomas displayed abundant multinucleated giant cells and palisading histiocytes around central necrosis or abscess formation. Thin-walled, broad fungal hyphae of Basidiobolus, with sparse septations, are surrounded by a radiating, intensely eosinophilic cuff (Splendore-Hoeppli phenomenon). These hyphae, visible with hematoxylin and eosin staining, were further highlighted with periodic acid-Schiff and Gomori methenamine silver staining. DISCUSSION: Basidiobolomycosis may mimic neoplastic lesions. Histologically, the characteristic features include broad, thin-walled septate hyphae surrounded by eosinophilic material, a finding that is accentuated by the Splendore-Hoeppli phenomenon. Microscopic examination, along with special stains such as periodic acid-Schiff (PAS) and Gomori methenamine silver, is essential for accurate diagnosis. CONCLUSION: Prompt recognition and appropriate antifungal therapy are vital for favorable patient outcomes. This report highlights the distinctive features of Basidiobolomycosis to raise awareness and understanding of this infrequent yet clinically significant fungal infection.
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Introduction: The composition and structure of natural soil are very complex, leading to the difficult contact between hydrophobic organic compounds and degrading-bacteria in contaminated soil, making pollutants hard to be removed from the soil. Several researches have reported the bacterial migration in unsaturated soil mediated by fungal hyphae, but bacterial movement in soil of different particle sizes or in heterogeneous soil was unclear. The remediation of contaminated soil enhanced by hyphae still needs further research. Methods: In this case, the migration and biodegradation of Diaphorobacter sp. LW2 in soil was investigated in presence of Pythium ultimum. Results: Hyphae could promote the growth and migration of LW2 in culture medium. It was also confirmed that LW2 was able to migrate in the growth direction and against the growth direction along hyphae. Mediated by hyphae, motile strain LW2 translocated over 3 cm in soil with different particle size (CS1, 1.0-2.0 mm; CS2, 0.5-1.0mm; MS, 0.25-0.5 mm and FS, <0.25 mm), and it need shorter time in bigger particle soils. In inhomogeneous soil, hyphae participated in the distribution of introduced bacteria, and the total number of bacteria increased. Pythium ultimum enhanced the migration and survival of LW2 in soil, improving the bioremediation of polluted soil. Discussion: The results of this study indicate that the mobilization of degrading bacteria mediated by Pythium ultimum in soil has great potential for application in bioremediation of contaminated soil.
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Research on endophytic fungi in desert plants, particularly the epiphytic or endophytic fungi of leaves, remains limited. In the extremely arid regions of northwest China, the ultra-xerophytic desert plant Haloxylon ammodendron harbors white fungi on its assimilating branches during autumn. The hyphae of these fungi intertwine, both internally and externally, comprising superficial, bridging, and endophytic types. The superficial hyphae attach to the surface of the assimilating branches and continuously grow and intersect, forming a thick layer of felt-like hyphae. This thick, felt-like layer of hyphae facilitates the adsorption of atmospheric water vapor on the surface of the hyphae or the assimilating branches, allowing H. ammodendron to capture atmospheric moisture, even under low humidity. Some superficial hyphae penetrate the cuticle into the epidermis, becoming bridging hyphae, which can rapidly transport water from the outside of the epidermis to the inside. The endophytic hyphae shuttle within the epidermis, achieving rapid water transfer within the epidermis of the assimilating branches. The presence of these three types of hyphae not only enables the assimilating branches of H. ammodendron to achieve rapid water absorption and transmission, but also facilitates the uptake of atmospheric water vapor under low humidity conditions. We discuss the mechanism by which the hyphae promote water absorption from the perspectives of hyphal composition, the formation of felt-like structures, and environmental conditions. We consider the presence of fungal hyphae on the surface of the H. ammodendron assimilating branches as an inevitable ecological process in arid environments. This study provides important theoretical insights into the mechanisms underlying the strong drought resistance of desert plants in extremely arid regions and offers strategies for desertification control.
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Candida albicans is a pathogenic fungus that undergoes morphological transitions between hyphal and yeast forms, adapting to diverse environmental stimuli and exhibiting distinct virulence. Existing research works on antifungal blue light (ABL) therapy have either focused solely on hyphae or neglected to differentiate between morphologies, obscuring potential differential effects. To address this gap, we established a novel dataset of 150 C. albicans-infected mouse skin tissue slice images with meticulously annotated hyphae and yeast. Eleven representative convolutional neural networks were trained and evaluated on this dataset using seven metrics to identify the optimal model for segmenting hyphae and yeast in original high pixel size images. Leveraging the segmentation results, we analyzed the differential impact of blue light on the invasion depth and density of both morphologies within the skin tissue. U-Net-BN outperformed other models in segmentation accuracy, achieving the best overall performance. While both hyphae and yeast exhibited significant reductions in invasion depth and density at the highest ABL dose (180 J/cm2), only yeast was significantly inhibited at the lower dose (135 J/cm2). This novel finding emphasizes the importance of developing more effective treatment strategies for both morphologies.
We studied the effects of blue light therapy on hyphal and yeast forms of Candida albicans. Through image segmentation techniques, we discovered that the changes in invasion depth and density differed between these two forms after exposure to blue light.
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Candida albicans , Hifas , Animais , Camundongos , Candida albicans/efeitos da radiação , Pele/microbiologia , Fototerapia/métodos , Processamento de Imagem Assistida por Computador/métodos , Luz , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Redes Neurais de Computação , Modelos Animais de Doenças , Candidíase/microbiologiaRESUMO
Mycorrhizae and their hyphae play critical roles in soil organic carbon (SOC) accumulation. However, their individual contributions to SOC components and stability under climate warming conditions remain unclear. This study investigated the effects of warming on the SOC pools of Picea asperata (an ectomycorrhizal plant) and Fargesia nitida (an arbuscular mycorrhizal plant) mycorrhizae/hyphae on the eastern Tibetan Plateau. The results indicated that mycorrhizae made greater contributions to SOC accumulation than hyphae did by increasing labile organic carbon (LOC) components, such as particle organic carbon (POC), easily oxidizable organic carbon, and microbial biomass carbon, especially under warming conditions. Plant species also had different effects on SOC composition, resulting in higher mineral-associated organic carbon (MAOC) contents in F. nitida plots than in P. asperata plots; consequently, the former favored SOC stability more than the latter, with a lower POC/MAOC. Partial least-squares path modelling further indicated that mycorrhizae/hyphae indirectly affected LOC pools, mainly by changing soil pH and enzyme activities. Warming had no significant effect on SOC content but did change SOC composition by reducing LOC through affecting soil pH and iron oxides and ultimately increasing SOC stability in the presence of mycorrhizae for both plants. Therefore, the mycorrhizae of both plants are major contributors to the variation of SOC components and stability under warming conditions.
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Micorrizas , Solo , Solo/química , Micorrizas/química , Carbono/análise , Hifas/química , Tibet , China , Plantas , Minerais , Microbiologia do SoloRESUMO
Strategies against the opportunistic fungal pathogen Candida albicans based on probiotic microorganisms represent a promising alternative to traditional antifungals. Here, we investigated the effects of Lactobacillaceae isolates from fermented foods or the human vagina, alone or in combination with the probiotic yeast Saccharomyces cerevisiae CNCM I-3856, against C. albicans in vitro. Nine out of nineteen tested strains of Lactobacillaceae inhibited growth of C. albicans with inhibition zones of 1-3 mm in spot assays. Five out of nineteen lactobacilli tested as such or in combination with S. cerevisiae CNCM I-3856 also significantly inhibited C. albicans hyphae formation, including Limosilactobacillus fermentum LS4 and L. fermentum LS5 resulting in respectively 62% and 78% hyphae inhibition compared to the control. Thirteen of the tested nineteen lactobacilli aggregated with the yeast form of C. albicans, with Lactiplantibacillus carotarum AMBF275 showing the strongest aggregation. The aggregation was enhanced when lactobacilli were combined with S. cerevisiae CNCM I-3856. No significant antagonistic effects were observed between the tested lactobacilli and S. cerevisiae CNCM I-3856. The multifactorial activity of Lactobacillaceae strains alone or combined with the probiotic S. cerevisiae CNCM I-3856 against C. albicans without antagonistic effects between the beneficial strains, paves the way for developing consortium probiotics for in vivo applications.
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Candida albicans , Lactobacillus , Probióticos , Saccharomyces cerevisiae , Candida albicans/efeitos dos fármacos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/efeitos dos fármacos , Probióticos/farmacologia , Lactobacillus/fisiologia , Humanos , Hifas/efeitos dos fármacos , Hifas/crescimento & desenvolvimento , Antibiose , Feminino , Vagina/microbiologiaRESUMO
Biological control uses naturally occurring antagonists such as bacteria or fungi for environmentally friendly control of plant pathogens. Bacillus spp. have been used for biocontrol of numerous plant and insect pests and are well-known to synthesize a variety of bioactive secondary metabolites. We hypothesized that bacteria isolated from agricultural soil would be effective antagonists of soilborne fungal pathogens. Here, we show that the Delaware soil isolate Bacillus velezensis strain S4 has in vitro activity against soilborne and foliar plant pathogenic fungi, including two with a large host range, and one oomycete. Further, this strain shows putative protease and cellulase activity, consistent with our prior finding that the genome of this organism is highly enriched in antifungal and antimicrobial biosynthetic gene clusters. We demonstrate that this bacterium causes changes to the fungal and oomycete hyphae at the inhibition zone, with some of the hyphae forming bubble-like structures and irregular branching. We tested strain S4 against Magnaporthe oryzae spores, which typically form germ tubes and penetration structures called appressoria, on the surface of the leaf. Our results suggest that after 12 hours of incubation with the bacterium, fungal spores form germ tubes, but instead of producing appressoria, they appear to form rounded, bubble-like structures. Future work will investigate whether a single antifungal molecule induces all these effects, or if they are the result of a combination of bacterially produced antimicrobials.
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OBJECTIVES: Rhino-orbito-cerebral mucormycosis (ROCM), a rare angio-invasive fungal infection, had become a major outbreak during the second wave of the coronavirus disease (COVID-19) pandemic in India, with over 28,000 reported cases. The purpose of this study was to describe the imaging spectrum of ROCM, which may prove useful in prompt diagnosis, considering its grave prognosis in populations with a high load of immunosuppressed patients (e.g., COVID-19, HIV-AIDS, etc.). MATERIAL AND METHODS: Evaluation of the clinical data and imaging of patients with symptoms suspicious of mucormycosis of the craniofacial region was done. The diagnosis was made using computed tomography (CT) or magnetic resonance (MR) imaging, a biopsy, and culture. The data analysis was done using descriptive statistical methods. RESULTS: The sample group consisted of a total of 36 patients ranging from 33 years to 75 years of age, out of which 31 (86.11%) were male and five (13.8%) were female. A total of 30 (83.33%) patients had a positive correlation with COVID-19 infection, and 29 (80.55%) patients had a positive correlation with diabetes. The major presenting complaints were facial pain and swelling (20 patients; 55.55%). The intracranial spread was seen in 14 (38.88%) patients. Our study demonstrated a mortality rate of 38.88% (14 patients). CONCLUSION: ROCM, once considered to occur predominantly in diabetics, is increasingly being seen in other immunosuppressive patients, such as COVID-19. CT and MR imaging help provide an early diagnosis in conjunction with pathologic and microbiological correlations. Immediate correction of immunosuppression with the initiation of amphotericin B therapy combined with extensive and diligent surgical debridement of the diseased tissue is required.