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1.
mBio ; : e0199324, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39235230

RESUMEN

Malassezia globosa is a lipophilic basidiomycetous yeast that occurs abundantly in breast tumors and that may contribute to a shortened overall survival of breast cancer (BRAC) patients, suggesting that the yeast may participate in the carcinogenesis of BRAC. However, the mechanisms involved in the M. globosa-based acceleration of BRAC are unknown. Here, we show that M. globosa can colonize mammary tissue in 7,12-dimethylbenz[a] anthracene-induced mice. The abundance of M. globosa shortened the overall survival and increased the tumor incidence. Transcriptome data illustrated that IL-17A plays a key role in tumor growth due to M. globosa colonization, and tumor-associated macrophage infiltration was elevated during M. globosa colonization which triggers M2 polarization of macrophages via toll-like receptors 4/nuclear factor kappa-B (Nf-κB) signaling. Our results show that the expression of sphingosine kinase 1 (Sphk1) is increased in breast tumors after inoculation with M. globosa. Moreover, we discovered that Sphk1-specific small interfering RNA blocked the formation of lipid droplets, which can effectively alleviate the expression of the signal transducer and activator of the transcription 3 (STAT3)/Nf-κB pathway. Taken together, our results demonstrate that M. globosa could be a possible factor for the progression of BRAC. The mechanisms by which M. globosa promotes BRAC development involve the IL-17A/macrophage axis. Meanwhile, Sphk1 overexpression was induced by M. globosa infection, which also promoted the proliferation of MCF-7 cells.IMPORTANCELiterature has suggested that Malassezia globosa is associated with breast tumors; however, this association has not been confirmed. Here, we found that M. globosa colonizes in breast fat pads leading to tumor growth. As a lipophilic yeast, the expression of sphingosine kinase 1 (Sphk1) was upregulated to promote tumor growth after M. globosa colonization. Moreover, the IL-17A/macrophages axis plays a key role in mechanisms involved in the M. globosa-induced breast cancer acceleration from the tumor immune microenvironment perspective.

2.
Phytomedicine ; 130: 155542, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38823343

RESUMEN

BACKGROUND: Malassezia globosa is a commensal basidiomycetous yeast occurring on the skin that causes pityriasis versicolor (PV) and seborrheic dermatitis, but that has also been implicated in other dermatoses. Cinnamaldehyde (CM) has antibacterial, antioxidant, and anti-inflammatory activities, but the effect of CM on M. globosa-infected PV has not been clarified. PURPOSE: The study aimed to investigate the possible antifungal and antibiofilm activities of CM against M. globosa-infected PV in vivo and in vitro. METHODS: The broth microdilution method was used to determine the minimum inhibitory concentration (MIC) of CM against M. globosa. The crystal violet staining assay and XTT assay were used to investigate the inhibition of CM on biofilm formation and the eradication of mature biofilms. The visualizations of the biofilm and cell distribution in the biofilm matrix were performed with a scanning electron microscope and confocal laser scanning microscope. The kits of antioxidant kinase were used to determine the activities of oxidative stress markers in M. globosa-stimulated HaCaT cells. Western blot assays were used to evaluate the role of TLR2/NF-κB in vitro. Furthermore, the protective effect of CM was assessed in M. globosa-associated PV mice. The expressions of inflammatory cytokines and apoptosis were screened using ELISA assays. The expressions of interleukin-6 and tumor necrosis factor-α were measured by an immunohistochemistry method in vivo. RESULTS: Our results showed that the MIC of CM against planktonic cells of M. globosa was 4 µg/ml and treatment with 20 × MIC CM eradicated mature biofilms of M. globosa. In vitro, after CM treatment the levels of oxidative stress indicators (i.e., superoxide dismutase, catalase, glutathione) significantly increased, while the levels of malondialdehyde decreased. In addition, the expression of TLR2/NF-κB in HaCaT cells was significantly reduced after CM treatment. On the other hand, an in vivo therapeutic effect of CM was assessed against M. globosa-infected mice. The fungal load on the skin decreased after treatment with CM compared to the M. globosa-infected group. In addition, the uninfected animals showed a normal skin structure, whereas, the M. globosa-infected mice showed extensive infiltration of neutrophils in skin tissues that improved after treatment with CM. Meanwhile, the levels of inflammatory and apoptotic factors improved after CM treatment. CONCLUSION: Our results showed that CM inhibits the biofilm formation of M. globosa and eradicates mature biofilms of M. globosa. Treatment with CM significantly decreased oxidative stress, apoptosis, and inflammatory markers in the skin tissue and HaCaT cells. Hence, this study suggests that CM is a good candidate therapeutic agent against M. globosa-induced PV infections because of its antifungal, antibiofilm, and anti-inflammatory properties.


Asunto(s)
Acroleína , Antifúngicos , Biopelículas , Malassezia , Pruebas de Sensibilidad Microbiana , Tiña Versicolor , Receptor Toll-Like 2 , Biopelículas/efectos de los fármacos , Acroleína/análogos & derivados , Acroleína/farmacología , Animales , Malassezia/efectos de los fármacos , Humanos , Receptor Toll-Like 2/metabolismo , Tiña Versicolor/tratamiento farmacológico , Antifúngicos/farmacología , Ratones , Estrés Oxidativo/efectos de los fármacos , Células HaCaT , FN-kappa B/metabolismo , Interleucina-6/metabolismo , Antioxidantes/farmacología , Factor de Necrosis Tumoral alfa/metabolismo , Piel/efectos de los fármacos , Piel/microbiología
3.
BMC Genomics ; 24(1): 321, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37312063

RESUMEN

BACKGROUND: The Ustilaginales comprise hundreds of plant-parasitic fungi with a characteristic life cycle that directly links sexual reproduction and parasitism: One of the two mating-type loci codes for a transcription factor that not only facilitates mating, but also initiates the infection process. However, several species within the Ustilaginales have no described parasitic stage and were historically assigned to the genus Pseudozyma. Molecular studies have shown that the group is polyphyletic, with members being scattered in various lineages of the Ustilaginales. Together with recent findings of conserved fungal effectors in these non-parasitic species, this raises the question if parasitism has been lost recently and in multiple independent events or if there are hitherto undescribed parasitic stages of these fungi. RESULTS: In this study, we sequenced genomes of five Pseudozyma species together with six parasitic species from the Ustilaginales to compare their genomic capability to perform two central functions in sexual reproduction: mating and meiosis. While the loss of sexual capability is assumed in certain lineages and asexual species are common in Asco- and Basidiomycota, we were able to successfully annotate potentially functional mating and meiosis genes that are conserved throughout the whole group. CONCLUSION: Our data suggest that at least the key functions of a sexual lifestyle are maintained in the analyzed genomes, challenging the current understanding of the so-called asexual species with respect to their evolution and ecological role.


Asunto(s)
Ustilaginales , Ustilaginales/genética , Reproducción/genética , Genómica , Comunicación Celular , Meiosis/genética
4.
Sci Rep ; 13(1): 6308, 2023 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-37072481

RESUMEN

Mitogenomes are essential due to their contribution to cell respiration. Recently they have also been implicated in fungal pathogenicity mechanisms. Members of the basidiomycetous yeast genus Malassezia are an important fungal component of the human skin microbiome, linked to various skin diseases, bloodstream infections, and they are increasingly implicated in gut diseases and certain cancers. In this study, the comparative analysis of Malassezia mitogenomes contributed to phylogenetic tree construction for all species. The mitogenomes presented significant size and gene order diversity which correlates to their phylogeny. Most importantly, they showed the inclusion of large inverted repeats (LIRs) and G-quadruplex (G4) DNA elements, rendering Malassezia mitogenomes a valuable test case for elucidating the evolutionary mechanisms responsible for this genome diversity. Both LIRs and G4s coexist and convergently evolved to provide genome stability through recombination. This mechanism is common in chloroplasts but, hitherto, rarely found in mitogenomes.


Asunto(s)
G-Cuádruplex , Genoma Mitocondrial , Malassezia , Humanos , Malassezia/genética , Filogenia , Genoma Mitocondrial/genética , Mitocondrias/genética , ADN
5.
mBio ; 13(2): e0385321, 2022 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-35404119

RESUMEN

Malassezia species are important fungal skin commensals and are part of the normal microbiota of humans and other animals. However, under certain circumstances these fungi can also display a pathogenic behavior. For example, Malassezia furfur is a common commensal of human skin and yet is often responsible for skin disorders but also systemic infections. Comparative genomics analysis of M. furfur revealed that some isolates have a hybrid origin, similar to several other recently described hybrid fungal pathogens. Because hybrid species exhibit genomic plasticity that can impact phenotypes, we sought to elucidate the genomic evolution and phenotypic characteristics of M. furfur hybrids in comparison to their parental lineages. To this end, we performed a comparative genomics analysis between hybrid strains and their presumptive parental lineages and assessed phenotypic characteristics. Our results provide evidence that at least two distinct hybridization events occurred between the same parental lineages and that the parental strains may have originally been hybrids themselves. Analysis of the mating-type locus reveals that M. furfur has a pseudobipolar mating system and provides evidence that after sexual liaisons of mating compatible cells, hybridization involved cell-cell fusion leading to a diploid/aneuploid state. This study provides new insights into the evolutionary trajectory of M. furfur and contributes with valuable genomic resources for future pathogenicity studies. IMPORTANCEMalassezia furfur is a common commensal member of human/animal microbiota that is also associated with several pathogenic states. Recent studies report involvement of Malassezia species in Crohn's disease, a type of inflammatory bowel disease, pancreatic cancer progression, and exacerbation of cystic fibrosis. A recent genomics analysis of M. furfur revealed the existence of hybrid isolates and identified their putative parental lineages. In this study, we explored the genomic and phenotypic features of these hybrids in comparison to their putative parental lineages. Our results revealed the existence of a pseudobipolar mating system in this species and showed evidence for the occurrence of multiple hybridization events in the evolutionary trajectory of M. furfur. These findings significantly advance our understanding of the evolution of this commensal microbe and are relevant for future studies exploring the role of hybridization in the adaptation to new niches or environments, including the emergence of pathogenicity.


Asunto(s)
Malassezia , Enfermedades de la Piel , Animales , Malassezia/genética , Fenotipo , Piel/microbiología
6.
FEMS Yeast Res ; 21(7)2021 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-34562093

RESUMEN

Malassezia furfur is a yeast species belonging to Malasseziomycetes, Ustilaginomycotina and Basidiomycota that is found on healthy warm-blooded animal skin, but also involved in various skin disorders like seborrheic dermatitis/dandruff and pityriasis versicolor. Moreover, Malassezia are associated with bloodstream infections, Crohn's disease and pancreatic carcinoma. Recent advances in Malassezia genomics and genetics have focused on the nuclear genome. In this work, we present the M. furfur mitochondrial (mt) genetic heterogenicity with full analysis of 14 novel and six available M. furfur mt genomes. The mitogenome analysis reveals a mt gene content typical for fungi, including identification of variable mt regions suitable for intra-species discrimination. Three of them, namely the trnK-atp6 and cox3-nad3 intergenic regions and intron 2 of the cob gene, were selected for primer design to identify strain differences. Malassezia furfur strains belonging to known genetic variable clusters, based on AFLP and nuclear loci, were assessed for their mt variation using PCR amplification and sequencing. The results suggest that these mt regions are excellent molecular markers for the typing of M. furfur strains and may provide added value to nuclear regions when assessing evolutionary relationships at the intraspecies level.


Asunto(s)
Genoma Mitocondrial , Malassezia , Tiña Versicolor , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Animales , Malassezia/genética , Mitocondrias
8.
J Antimicrob Chemother ; 76(2): 418-422, 2021 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-33175162

RESUMEN

BACKGROUND: Echinocandin resistance rarely occurs in clinical Candida parapsilosis isolates and the underlying mechanism is unknown. OBJECTIVES: To determine the prevalence of echinocandin resistance and the underlying mechanism for a large collection of C. parapsilosis blood isolates and to determine whether the echinocandin-resistant isolates were clonally related. METHODS: C. parapsilosis blood isolates (n = 213) were subjected to antifungal susceptibility testing (CLSI M27), for micafungin, anidulafungin, amphotericin B and, if appropriate, caspofungin. Hotspot (HS) 1 and HS2 of FKS1 were sequenced for all isolates (n = 213) and microsatellite typing was performed for echinocandin-resistant isolates. RESULTS: All isolates were susceptible to amphotericin B and two isolates were intermediate to anidulafungin (MIC = 4 mg/L), while micafungin resistance was noted in four isolates (MIC >8 mg/L); three of which were also fluconazole resistant and therefore were MDR. Interestingly, micafungin-resistant isolates, but not those intermediate to anidulafungin, carried novel mutation R658G in HS1 of Fks1p; three of which also harboured Y132F+K143R in Erg11. The first isolate (MICR1) was recovered in November 2017 from a patient admitted to paediatric gastroenterology who showed therapeutic failure under caspofungin treatment. MICR2-MICR4 were collected during 2018-19 and were recovered from three echinocandin-naive paediatric-surgery patients; the isolates shared the same genotype. CONCLUSIONS: Herein, for the first time (to the best of our knowledge), we identified micafungin-resistant C. parapsilosis blood isolates harbouring a novel mutation in HS1 of FKS1, which was likely attributable to in vitro micafungin resistance and in vivo caspofungin therapeutic failure. The acquisition of micafungin-resistant C. parapsilosis isolates in echinocandin-naive patients likely implicates clonal expansion, as supported by the close genetic relatedness of MICR2-MICR4.


Asunto(s)
Antifúngicos , Candida parapsilosis , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Niño , Farmacorresistencia Fúngica , Equinocandinas/farmacología , Humanos , Micafungina/farmacología , Pruebas de Sensibilidad Microbiana , Mutación
9.
J Infect ; 81(4): 634-638, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32590007

RESUMEN

A 31-year-old man presented with cryptococcal meningitis (CM) without typical clinical characteristics, but with abnormal walking, difficult leg lifting and frequent falling. He was admitted to Peking Union Medical College Hospital. After multiple tests failed to identify the pathogen, single-cell sequencing (scS) was used to test the cerebrospinal fluid (CSF). Comparing the sequence obtained from single-cell sequencing with the reference database, it was found that the infection was caused by Cryptococcus gattii sensu stricto (AFLP4/VGI genotype). Cryptococcus is difficult to cultivate from complex body fluids. The etiological agent of this patient was identified and the patient was treated. This is the first case in which scS was used to detect and identify fungal pathogen after conventional testing failed to identify the cause of the disease. This report demonstrates that the scS approach can be used to generate fungal genome sequences directly from the CSF of a CM patient. The scS technology could become a powerful tool to precise detect microscopically visible but uncultured pathogens in clinical samples.


Asunto(s)
Criptococosis , Cryptococcus gattii , Cryptococcus neoformans , Meningitis Criptocócica , Adulto , Criptococosis/diagnóstico , Cryptococcus gattii/genética , Genotipo , Humanos , Masculino , Meningitis Criptocócica/diagnóstico
10.
Med Mycol ; 58(8): 1091-1101, 2020 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-32236482

RESUMEN

Chlorogenic acid (CHA) and gallic acid (GA) are safe natural phenolic compounds that are used as enhancers of some drugs in influencing antioxidant, anticancer, and antibacterial activities. Among fungi, Candida spp. and Malassezia spp. are characterized by an increasing prevalence of multidrug resistance phenomena and by a high morbidity and mortality of their infections. No data are available about the efficacy of CHA and GA combined with azoles on the antifungal susceptibility and on the virulence of both fungi. Therefore, their antifungal and antivirulence effects have been tested in combination with fluconazole (FLZ) or ketoconazole (KTZ) on 23 Candida spp. and 8 M. furfur isolates. Broth microdilution chequerboard, time-kill studies, and extracellular enzymes (phospholipase and hemolytic) activities were evaluated, displaying a synergistic antifungal action between CHA or GA and FLZ or KTZ on C. albicans, C. bovina, and C. parapsilosis, and antagonistic antifungal effects on M. furfur and Pichia kudriavzevii (Candida krusei) isolates. The time-kill studies confirmed the chequerboard findings, showing fungicidal inhibitory effect only when the GA was combined with azoles on Candida strains. However, the combination of phenolics with azoles had no effect on the virulence of the tested isolates. Our study indicates that the combination between natural products and conventional drugs could be an efficient strategy for combating azole resistance and for controlling fungistatic effects of azole drugs.


Asunto(s)
Antifúngicos/farmacología , Azoles/farmacología , Candida/efectos de los fármacos , Ácido Clorogénico/farmacología , Farmacorresistencia Fúngica Múltiple/efectos de los fármacos , Ácido Gálico/farmacología , Malassezia/efectos de los fármacos , Animales , Candida/aislamiento & purificación , Candida/metabolismo , Candida/patogenicidad , Candidiasis/microbiología , Dermatomicosis/microbiología , Sinergismo Farmacológico , Humanos , Malassezia/aislamiento & purificación , Malassezia/metabolismo , Malassezia/patogenicidad , Pruebas de Sensibilidad Microbiana , Fosfolipasas/metabolismo , Especificidad de la Especie , Virulencia/efectos de los fármacos
11.
PLoS Negl Trop Dis ; 14(1): e0007845, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31940343

RESUMEN

The genus Madurella comprising four species, M. fahalii, M. mycetomatis, M. pseudomycetomatis, and M. tropicana, represents the prevalent cause of eumycetoma worldwide. The four species are phenotypically similar and cause an invariable clinical picture, but differ markedly in their susceptibility to antifungal drugs, and epidemiological pattern. Therefore, specific identification is required for optimal management of Madurella infection and to reveal proper epidemiology of the species. In this study, a novel multiplex real-time PCR targeting the four Madurella species was developed and standardized. Evaluation of the assay using reference strains of the target and non-target species resulted in 100% specificity, high analytical reproducibility (R2 values >0.99) and a lowest detection limit of 3 pg target DNA. The accuracy of the real-time PCR was further assessed using biopsies from eumycetoma suspected patients. Unlike culture and DNA sequencing as gold standard diagnostic methods, the real-time PCR yielded accurate diagnosis with specific identification of the causative species in three hours compared to one or two weeks required for culture. The novel method reduces turnaround time as well as labor intensity and high costs associated with current reference methods.


Asunto(s)
Madurella/clasificación , Madurella/genética , Micetoma/diagnóstico , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Biopsia , ADN de Hongos/análisis , Humanos , Micetoma/microbiología , Sensibilidad y Especificidad
12.
Front Microbiol ; 10: 1677, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31447794

RESUMEN

Aspergillus are ubiquitous mold species that infect immunocompetent and immunocompromised patients. The symptoms are diverse and range from allergic reactions, bronchopulmonary infection, and bronchitis, to invasive aspergillosis. The aim of this study was to characterize 70 Aspergillus isolates recovered from clinical specimens of patients with various clinical conditions presented at Hamad general hospital in Doha, Qatar, by using molecular methods and to determine their in vitro antifungal susceptibility patterns using the Clinical and Laboratory Standards Institute (CLSI) M38-A2 reference method. Fourteen Aspergillus species were identified by sequencing ß-tubulin and calmodulin genes, including 10 rare and cryptic species not commonly recovered from human clinical specimens. Aspergillus welwitschiae is reported in this study for the first time in patients with fungal rhinosinusitis (n = 6) and one patient with a lower respiratory infection. Moreover, Aspergillus pseudonomius is reported in a patient with fungal rhinosinusitis which is considered as the first report ever from clinical specimens. In addition, Aspergillus sublatus is reported for the first time in a patient with cystic fibrosis. In general, our Aspergillus strains exhibited low MIC values for most of the antifungal drugs tested. One strain of Aspergillus fumigatus showed high MECs for echinocandins and low MICs for the rest of the drugs tested. Another strain of A. fumigatus exhibited high MIC for itraconazole and categorized as non-wild type. These findings require further analysis of their molecular basis of resistance. In conclusion, reliable identification of Aspergillus species is achieved by using molecular sequencing, especially for the emerging rare and cryptic species. They are mostly indistinguishable by conventional methods and might exhibit variable antifungal susceptibility profiles. Moreover, investigation of the antifungal susceptibility patterns is necessary for improved antifungal therapy against aspergillosis.

13.
Future Microbiol ; 14: 859-866, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31165635

RESUMEN

Aim: This study aims to evaluate lumbar drainage (LD) for controlling refractory intracranial hypertension among non-HIV cryptococcal meningitis patients. Patients & methods: A case-control study was designed to compare LD (case) with repeated lumbar puncture (control). Results: Both LD and repeated lumbar puncture can efficiently control refractory intracranial hypertension. LD group showed better clinical symptom remission, such as lower rate of headache, vision disorders, signs of meningeal irritation and conscious disturbance, than control group. LD group was reported with higher intracranial pressure reduction (173.75 ± 17.72 mmH2O) than those among control group (113.50 ± 14.94 mmH2O; p < 0.05). Conclusion: LD is an effective and safe alternative to control refractory intracranial hypertension in HIV-negative cryptococcal meningitis patients.


Asunto(s)
Drenaje , Hipertensión Intracraneal/terapia , Meningitis Criptocócica/terapia , Punción Espinal , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Hipertensión Intracraneal/fisiopatología , Masculino , Meningitis Criptocócica/fisiopatología , Persona de Mediana Edad , Resultado del Tratamiento
14.
J Oral Microbiol ; 11(1): 1601061, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31044032

RESUMEN

Background: Oral candidiasis (OC) has a profound effect on the life quality of immunocompromised patients, such as those undergoing chemotherapy. Objective: Systematic investigation of clinical outcome and microbiological features of yeast isolates recovered from the oral cavity of 150 Iranian patients with hematological malignancies. Design: MALDI-TOF MS, 21-plex PCR, and rDNA sequencing were used for identification. Antifungal susceptibility testing (broth microdilution, CLSI M27-A3/S4) and genotypic diversity of yeast isolates (amplified fragment length polymorphism) were assessed. Results: Nystatin treatment resulted in 70% therapeutic failure and administration of 150 mg fluconazole (FLZ) + nystatin for patients with OC relapse showed 70% clinical failure. Previous history of OC was significantly correlated with FLZ treatment requirement and nystatin failure (P = 0.005, α < 0.05). Candida albicans (80.3%) and Kluyveromyces marxianus (C. kefyr) (12.7%) were the two most prevalent yeast species isolated. FLZ and AMB exhibited the highest geometric mean values. 21-PCR showed 98.9% agreement with MALDI-TOF MS. K. marxianus isolates had the same genotype, while C. albicans isolates grouped in 15 genotypes. Conclusions: Marked rate of therapeutic failure of nystatin necessitated OC treatment with systemic antifungals. K. marxianus was the second most prevalent yeast and 21-plex PCR could be considered as an inexpensive identification tool.

15.
Int J Syst Evol Microbiol ; 69(3): 839-845, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30694170

RESUMEN

Two strains, 1Y129 and 3Y383, which represent a single novel anamorphic yeast species, were isolated from the Arabian Gulf surrounding Qatar. The two strains have identical sequences in the D1/D2 domains of the large subunit (LSU) and the internal transcribed spacer (ITS) regions of the rRNA gene. On the basis of this sequence analysis the two strains were found to be closely related to Cystobasidium slooffiae CBS5706T with 97. 3 % nucleotide substitutions (12 nt; four gaps) in D1/D2 regions of the LSU rRNA and 97.0 % nucleotide substitutions (14 nt; two gaps) in ITS regions. In contrast to Cystobasidium halotolerans sp. nov., the related species Cystobasidium slooffiae, Cystobasidium minutum and Cystobasidium fimetarium were unable to assimilate d-galactose, soluble starch, galactitol, methanol or nitrate, and grew at 37 °C. The name proposed for this undescribed species is Cystobasidium halotolerans sp. nov. The ex-type strain is QCC/Y31/17 (=MUCL057192=CGMCC2.5570).


Asunto(s)
Basidiomycota/clasificación , Filogenia , Agua de Mar/microbiología , Basidiomycota/aislamiento & purificación , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Técnicas de Tipificación Micológica , Qatar , Análisis de Secuencia de ADN
16.
Med Mycol Case Rep ; 22: 18-20, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30094133

RESUMEN

Cystic fibrosis (CF) patients are colonized with a multitude of bacteria and fungi. From respiratory samples of two CF patients in our institute, a difficult to identify yeast was isolated repeatedly. This yeast was eventually identified as Cutaneotrichosporon (Cryptococcus) cyanovorans by internal transcribed spacer (ITS) and ribosomal large subunit (LSU) sequencing. C. cyanovorans is a basidiomycetous yeast originally reported as environmental isolate from South African soil and has not been described before as clinical isolate from CF patients.

17.
BMC Infect Dis ; 18(1): 24, 2018 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-29310582

RESUMEN

BACKGROUND: Opportunistic infections due to Candida species occur frequently in cancer patients because of their inherent immunosuppression. The aim of the present study was to investigate the epidemiology of yeast species from the oral cavity of patients during treatment for oncological and haematological malignancies. METHODS: MALDI-TOF was performed to identify yeasts isolated from the oral cavity of 350 cancer patients. Moreover, antifungal susceptibility testing was performed in according to CLSI guidelines (M27-A3). RESULTS: Among 162 yeasts and yeast-like fungi isolated from the oral cavity of cancer patients, Candida albicans was the most common species (50.6%), followed by Candida glabrata (24.7%), Pichia kudriavzevii (Candida krusei (9.9%)), Candida tropicalis (4.3%), Candida dubliniensis (3.7%), Kluyveromyces marxianus (Candida kefyr (3.7%)) and Candida parapsilosis (1%). In addition, uncommon yeast species i.e., Saprochaete capitata, Saccharomyces cerevisiae, Clavispora lusitaniae (C. lusitaniae) and Pichia kluyveri (C. eremophila) were recovered from oral lesions. Oral colonization by C. albicans, non-albicans Candida species and uncommon yeasts were as follow; 55%, 44% and 1%, whereas oral infection due to C. albicans was 33.3%, non-albicans Candida species 60.6%, and uncommon yeasts 6.1%. Poor oral hygiene and xerostomia were identified as independent risk factors associated with oral yeast colonization. The overall resistance to fluconazole was 11.7% (19/162). Low MIC values were observed for anidulafungin for all Candida and uncommon yeast species. CONCLUSIONS: This current study provides insight into the prevalence and susceptibility profiles of Candida species, including emerging Candida species and uncommon yeasts, isolated from the oral cavity of Iranian cancer patients. The incidence of oral candidiasis was higher amongst patients with hematological malignancies. The majority of oral infections were caused by non-albicans Candida species which were often more resistant to anti-fungal agents. Our findings suggest that anidulafungin should be used as antifungal of choice for prophylaxis in clinically high-risk patients with documented oral colonization or infection.


Asunto(s)
Candida/química , Candidiasis Bucal/diagnóstico , Neoplasias/patología , Pichia/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antifúngicos/farmacología , Candida/efectos de los fármacos , Candida/aislamiento & purificación , Candidiasis Bucal/complicaciones , Femenino , Fluconazol/farmacología , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Boca/microbiología , Neoplasias/complicaciones , Pichia/efectos de los fármacos , Pichia/aislamiento & purificación , Prevalencia , Factores de Riesgo , Saccharomycetales/efectos de los fármacos , Saccharomycetales/aislamiento & purificación , Xerostomía/etiología , Adulto Joven
18.
Microb Pathog ; 115: 353-357, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29292174

RESUMEN

Opportunistic infections due to Candida species occur frequently in intensive care settings. We investigated the prevalence of Candida species among 65 clinical specimens obtained from 200 cancer patients by phenotypic and molecular (ITS sequencing and AFLP) methods. Among the 65 yeast isolates, Candida albicans was the most commonly isolated species (n = 34, 52.3%), whereas other Candida species comprised 47.7% (n = 31) and consisted of Candida glabrata (n = 14, 21.5%), Candida tropicalis (n = 5, 7.7%) and uncommon Candida species (n = 12, 18.5%) such as Candida pelliculosa (n = 3, 4.6%), Pichia kudriavzevii (= Candida krusei, n = 2, 3.1%), Candida orthopsilosis (n = 2, 3.1%), Candida parapsilosis (n = 1, 1.5%), Candida infanticola (n = 2, 3.1%), Candida spencermartinsiae (n = 1, 1.5%), and Kluyveromyces marxianus (=Candida kefyr, n = 1, 1.5%). Candida infanticola and Candida spencermartinsiae were recovered from oral lesions of cancer patients. Matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) easily confirmed these isolates as less common Candida isolates (4.6%). The in vitro antifungal susceptibilities of C. spencermartinsiae and the two strains of C. infanticola were determined according to CLSI guidelines (M27-A3). MIC results among these isolates showed they were susceptible to isavuconazole, posaconazole and voriconazole, however, fluconazole and caspofungin had high MIC values. These Candida species that may occur more commonly in infections remain unnoticed using commonly used phenotypical methods in routine microbiology laboratories. MALDI-TOF MS proved to be a more fast and robust diagnostic technique for identification of the yeasts isolated from different clinical specimens of cancer patients.


Asunto(s)
Antifúngicos/farmacología , Candida/clasificación , Candida/efectos de los fármacos , Candidiasis/epidemiología , Kluyveromyces/efectos de los fármacos , Neoplasias/microbiología , Infecciones Oportunistas/epidemiología , Pichia/efectos de los fármacos , Adolescente , Candida/aislamiento & purificación , Candidiasis/diagnóstico , Candidiasis/microbiología , Caspofungina , Preescolar , Equinocandinas/farmacología , Fluconazol/farmacología , Humanos , Kluyveromyces/clasificación , Kluyveromyces/aislamiento & purificación , Lipopéptidos/farmacología , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Nitrilos/farmacología , Infecciones Oportunistas/diagnóstico , Infecciones Oportunistas/microbiología , Pichia/clasificación , Pichia/aislamiento & purificación , Piridinas/farmacología , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Triazoles/farmacología , Voriconazol/farmacología
19.
Med Mycol ; 56(7): 828-833, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-29294025

RESUMEN

The occurrence of Malassezia spp. bloodstream infections (BSIs) in neonatal intensive care unit was evaluated by using pediatric Isolator, BacT/Alert systems and central venous catheter (CVC) culture. The efficacy of BacT/Alert system in detecting Malassezia was assessed by conventional procedures, culturing 1 ml of bottle content before incubation and by studying the survival of Malassezia spp. strains in BacT/Alert bottles. Of the 492 neonates enrolled, blood was collected by pediatric Isolator (290 patients; group I) or by BacT/Alert bottles (202 patients; group II). The survival of Malassezia furfur and Malassezia pachydermatis in BacT/Alert bottles was evaluated by culturing the inoculum suspension (from 106 to 10 colony-forming units, cfu/ml) and assessing the cfu/ml for 15 days. In total, 15 Malassezia BSIs were detected, of which six (2.1%) from both blood and CVC culture in Dixon agar (DixA) in patients belong to group I (blood collected by paediatric Isolator tube) and nine (4.4%) only from CVC culture in DixA in patients of group II (blood collected by BacT/Alert bottle). Only one patient (0.5%) from group II scored positive for M. furfur also by culturing in DixA 1 ml blood content of BacT/Alert bottle before incubation in BacT/Alert system.M. furfur population size in BacT/Alert bottles decreased during the incubation time, whereas that of M. pachydermatis increased. The BacT/Alert system detected M. pachydermatis even at very low concentration (i.e., 10 cfu/ml) but not any positive blood culture for M. furfur. For a correct diagnosis of Malassezia furfur BSI, the blood should be culture in lipid-enriched fungal medium, and the BacT/Alert system implemented by adding lipid substrates to increase the method sensibility. Finally, CVC cultures on lipid-supplemented media may be proposed as a routine procedure to diagnose the Malassezia fungemia.


Asunto(s)
Cultivo de Sangre/métodos , Fungemia/diagnóstico , Fungemia/microbiología , Malassezia/aislamiento & purificación , Técnicas Microbiológicas/métodos , Manejo de Especímenes/métodos , Humanos , Lactante , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Malassezia/fisiología , Viabilidad Microbiana , Sensibilidad y Especificidad
20.
Mycoses ; 60(11): 706-713, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28857298

RESUMEN

Diabetes mellitus II (DM II) is a newly defined independent factor contributing to the morbidity and mortality of cryptococcosis. This retrospective case analysis aims to explore the epidemiology, clinical profile and strain characteristics of cryptococcosis in Chinese DM II patients. This study included 30 cases of cryptococcosis with DM II occurring from 1993 to 2015 in mainland China. The hospital-based prevalence of cryptococcosis in DM II was 0.21%. The mean age of the patients was 56.1 years (95% confidence interval: 51.5, 60.6), and 93% of the patients were older than 40 years. Sixty-two per cent of the patients experienced untreated or poorly controlled blood glucose before infection. Multilocus sequence typing analysis categorised all cultured strains as Cryptococcus neoformans and sequence type 5. Sixty-nine per cent of pulmonary cryptococcosis patients experienced misdiagnoses and treatment delays. Sixty per cent of cryptococcal meningitis patients received substandard antifungal therapy. The overall death rate was 33%. Considering the large population size of DM II patients in China, improved attention should be paid to the high prevalence of cryptococcosis as revealed by us. We also emphasised the importance of blood glucose control for infection prevention, especially among the elderly.


Asunto(s)
Criptococosis/epidemiología , Cryptococcus neoformans/aislamiento & purificación , Diabetes Mellitus Tipo 2/epidemiología , Meningitis Criptocócica/epidemiología , Anciano , China/epidemiología , Criptococosis/complicaciones , Criptococosis/diagnóstico , Criptococosis/microbiología , Cryptococcus neoformans/genética , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Femenino , Genotipo , Humanos , Masculino , Meningitis Criptocócica/complicaciones , Meningitis Criptocócica/diagnóstico , Meningitis Criptocócica/microbiología , Persona de Mediana Edad , Tipificación de Secuencias Multilocus , Estudios Retrospectivos
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