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Candidiasis is an infection caused by Candida spp., mostly Candida albicans. Infection with Candida spp. in immunocompetent individuals is often limited to the mouth, genital area or skin. However, patients who are immunocompromised due to infections or medications including corticosteroids or anticancer drugs are more susceptible to systemic candidiasis and candidemia. Upon C. albicans infections, the pathogenic yeasts enter the bloodstream and disseminate to the remote organs, leading to the formation of germ tube. Dimorphic adaptation is one of contributing virulent factors in C. albicans, which is responsible for disease pathogenesis and severity. However, little is known about whether differences among human ABO blood groups facilitate the development of C. albicans germ tube. Therefore, this study investigated the germ tube formation of C. albicans that grown in human serums from different ABO blood groups. Human pool serums varying ABO blood groups from healthy individuals were tested for C. albicans germ tube induction. After incubation for 2 h at 37 °C, the rate of germ tube formation at 15-min intervals was determined. Serum from human blood group A exhibited the highest rate of germ tube formation. Humans with blood group A exhibited the unique serum biochemical structure that possibly helps facilitate germ tube formation during C. albicans infection. [ABSTRACT FROM AUTHOR]

Background and purpose: Subcutaneous infections caused by Scedosporium apiospermum present as chronic eumycetomatous manifestations in both immunocompromised and immunocompetent individuals. Serious adverse effects/toxicities from the long-term use of antifungal drugs and antifungal resistance have been reported in patients with S. apiospermum infections. The present study aimed to determine the anti-S. apiospermum activities of fungal quorum sensing molecule known as tryptophol (TOH) and to develop a TOH-containing emulgel for treating S. apiospermum eumycetoma. Experimental approach: Anti-S. apiospermum activities of TOH were determined and compared with voriconazole. Effects of TOH on S. apiospermum biofilm formation and human foreskin fibroblast (HFF)-1 cell cytotoxicity were determined. Moreover, TOH-containing emulgel was developed and physical properties, in vitro, and in vivo antifungal activities against S. apiospermum eumycetoma were evaluated. Findings/Results: The minimal concentration of TOH at 100 µM exhibited anti-S. apiospermum activities by reducing growth rate, germination rate, and biofilm formation with less cytotoxicity to HFF-1 cells than voriconazole. Further study on the development of an emulgel revealed that TOH-containing emulgel exhibited excellent physical properties including homogeneity, consistency, and stability. Treatment by TOH-containing emulgel significantly reduced subcutaneous mass in a mouse model of S. apiospermum eumycetoma. The histopathological assessment showed marked improvement after 14 days of TOH-containing emulgel treatment. Conclusion and implications: TOH could be used as an anti-fungal agent against S. apiospermum infections. A novel and stable TOH-containing emulgel was developed with excellent anti-S. apiospermum activities suggesting the utilization of TOH-containing emulgel as an innovative therapeutic approach in the treatment of S. apiospermum eumycetoma. [ABSTRACT FROM AUTHOR]

Saponins are secondary metabolite compounds that can be found in sea cucumbers (Holothuroidea spp.). However, little is known about how saponin‐rich extracts from Holothuria leucospilota can delay and prolong the lifespan of the whole organism. In this study, anti‐aging effects of H. leucospilota extracts were studied on Caenorhabditis elegans. NMR analysis revealed that body wall n‐butanol‐extract of H. leucospilota (BW‐BU) is saponin‐rich. BW‐BU extracts exhibited antioxidant activities by 2,2ʹ‐diphenyl‐2‐picrylhydrazyl assay (EC50 = 10.23 ± 0.12 mg/ml) and 2,2ʹ‐azino‐bis‐3‐ethylbenzthiazoline‐6‐sulphonic acid assay (EC50 = 3.91 ± 0.04 mg/ml). BW‐BU extracts increased lifespan of L4 and L1 C. elegans (5.92% and 15.76%, respectively), which also increased worm growth, stress resistance, and reduced biomarkers for aging. BW‐BU extracts activated DAF‐16 nuclear localization and upregulated daf‐16 and DAF‐16 target genes expression. Taken together, this study revealed the evidences on anti‐aging activities of saponin‐rich extracts from H. leucospilota, which can extend lifespan of C. elegans via daf‐16. Practical applications: In recent years, age‐associated chronic diseases have had a significant impact on quality of life. Many natural compounds exhibit anti‐aging activities, especially in sea cucumber, H. leucospilota. Our results indicated that H. leucospilota is good for health. Extracts from H. leucospilota contain a bioactive compound that can be potentially used to promote longevity and disease prevention in aging. [ABSTRACT FROM AUTHOR]

Candida albicans can cause infections ranging from superficial skin infections to life-threateningsystemic infections in immunocompromised hosts. Although several C. albicans virulence factorsare widely discussed in great detail, intrinsic host determinants that are critical for C. albicanspathogenesis remain less interested and poorly understood. In view of this, a model of Caenorhabditiselegans was used to study host longevity and immunity in response to C. albicans pathogenesis.The influence of C. albicans in pathological and survival aspects was evaluated using C. elegans.C. albicans hyphal formation in different C. elegans genetic backgrounds was evaluated. Moreover,several C. elegans fluorescent proteins as gene expression markers upon C. albicans infectionswere evaluated. C. albicans is pathogenic to C. elegans and reduces the lifespan of C. elegans inassociation with repression of the insulin/IGF-1-like signaling (IIS) pathway. Moreover, repressionof DAF-16/forkhead transcription factor increases aggressiveness of C. albicans by enhancing hyphalformation. In addition, infection of C. albicans increases lipofuscin accumulation, promotes DAF-16nuclear translocation, increases superoxide dismutase (SOD-3) expression, which coordinately linksbetween aging and innate immunity. Thus, we demonstrate here the strategy to utilize C. elegans asa model host to elucidate host genetic determinants that provide insights into the pathogenesis ofC. albicans infections.

Soil fungal communities play an important role in regulating biogeochemical transformations, yet soil-related fungal pathogens are emerging threats to humans. Our previous studies have revealed the pathogenic Scedosporium species in soils samples from public parks with high human activities in Thailand. However, measurement and survey of soil fungal communities in other areas with high human/animal activities, such as the pigsty, are poorly determined. In this study, soil fungal pathogens from a pigsty were isolated and identified. Soil samples were collected from the surrounding drainage areas. Fungal species were identified using morphological and molecular analyses. Isolation of soil samples from the pigsty revealed at least 11 species that have been identified. The most abundant fungal species belonged to genera Aspergillus and Penicillium. Moreover, Scedo-Select III culturing and phylogenetic analysis with β-tubulin gene sequencing revealed the three environmental isolates of Scedosporium species, which were consistent with the S.apiospermum. These three Scedosporium isolates were susceptible to voriconazole and caused pathological characteristics of scedosporiosis similar to S. apiospermum in vivo. In conclusion, our findings contribute towards a better understanding of soil-borne pathogenic fungi in the pigsty. The isolation of Scedosporium species with pathogenic potentials in the present study can be beneficial for the management of public health surveillance, epidemiologists, as well as physicians to reduce the risk of soil fungal contamination among pigsty workers.

Candida albicans is an opportunistic fungal infectious agent that can cause cutaneous candidiasis in humans. Biofilms formation of C. albicans is thought to be the major cause of antifungal drug resistance. Despite numerous studies conducted on C. albicans biofilms, a comprehensive understanding of how C. albicans biofilms induced cutaneous candidiasis in humans and the development of a more effective targeted therapy remain poorly investigated. Available animal models of cutaneous candidiasis and in vitro human skin cell cultures do not fully reflect the actual human skin microenvironment or the disease pathogenesis. We investigated the molecular pathology of C. albicans infection using an in vitro biofabricated 3D skin. This in vitro biofabricated 3D skin comprises a fully humanized three-dimensional (3D) skin equivalent, consisting of a stratified terminally differentiated epidermis and an underlying dermal compartment. Antifungal drug susceptibility testing, histological and electron microscopy study, biofilms study, and pro-inflammatory cytokines analysis were conducted in C. albicans infected skin. Histological results revealed that C. albicans covered and produced biofilm on the in vitro biofabricated 3D skin, invading the skin compartments including epidermis and dermis. Elevation of proinflammatory cytokines including MMP-9, IL-1β, TNF-α, and IL-5 were examined in the C. albicans infected skin. However, treatment with itraconazole reduced the pathology of C. albicans infection. This study provides an alternative pathological model of cutaneous candidiasis, which can physiologically represent a close-up event during C. albicans. Moreover, it is rapid, cost-effective, and reproducible of the in vitro biofabricated 3D skin model, and may further highlight the importance of utilizing in vivo-like conditions to improve high-throughput screening for drug discovery against several antifungal drug resistant pathogens.

Skin infection from pathogenic dermatophyte, Epidermophytonfloccosum, can cause serious health complications, especially in immuno-compromised patients. Proteolytic enzymes secreted from E. floccosum are required for host tissue degradation, facilitating fungal invasion. However, little is known regarding host matrix metalloproteinase (MMP) expression during E. floccosum infection. In this study human foreskin fibroblast (HFF) cell line was used to determine MMP-9 protease activity by gelatin zymography and amount by ELISA. E. floccosum-induced HFF secretion of MMP-9 in a time dependent manner, but HFF cell viability decreased. Treatment with an MMP inhibitor (SB-3CT) caused reduction in E. floccosum-induced secreted MMP-9 and improvement in HFF cell viability. These findings indicate a possible control measure for protecting skin from E. floccosum infection.

Growing rates of fungal infections and increasing resistance against standard antifungal drugs can cause serious health problems. There is, therefore, increasing interest in the potential use of medicinal plants as novel antifungal agents. This study investigates the antifungal properties of crude plant extracts from ten medicinal plant species. Crude samples were extracted using the hot water extraction process. The minimum inhibitory concentrations (MIC) and diameter zone of inhibition were determined in each extract against ten fungal strains, and fluconazole was used as a positive control. The cytotoxicity of crude extracts on in vitro human skin fibroblast (HSF) cell models was determined by MTT assay. Of the ten crude extracts, Psidium guajava L. exhibited the highest antifungal activity, diameter zone of inhibition, and percentage HSF cell viability. Although all extracts exhibited antifungal activity, Psidium guajava L. had the greatest potential for developing antifungal treatments.