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2.
Med Mycol J ; 65(1): 17-21, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38417883

RESUMO

Disseminated trichosporonosis is a rare fungal infection whose risk factors are hematological malignancies and neutropenia. Recently, breakthrough Trichosporon infections after administration of micafungin, the first-line systemic antifungal agent in compromised hosts, have been widely recognized. A man in his seventies about 1 month into chemotherapy for acute megakaryoblastic leukemia presented with a worsening fever and dyspnea. The patient was being administered with empirical micafungin therapy for suspected candidiasis. As the symptoms progressed, scattered erythema appeared on the trunk, some with a dark red vesicle at the center. Blood cultures identified Trichosporon asahii, as did the specimen of the skin biopsy. On the basis also of the presence of pneumonia on chest computed tomography, we confirmed the diagnosis of disseminated trichosporonosis and changed the antifungal agent from micafungin to voriconazole. Blood culture turned out to be negative 1 month after administrating voriconazole. However, the patient died of the leukemia. Our review of previous reports on cutaneous manifestations of disseminated trichosporonosis revealed that despite their morphological diversity, erythema with a red papule or vesicle at the center, implying necrosis, was also observed in previous cases. Our case report suggests that dermatologists should be aware of skin manifestations of disseminated trichosporonosis after micafungin administration, especially in cases of hematological malignancies.


Assuntos
Neoplasias Hematológicas , Leucemia Megacarioblástica Aguda , Trichosporon , Tricosporonose , Masculino , Humanos , Micafungina , Antifúngicos/uso terapêutico , Voriconazol , Tricosporonose/diagnóstico , Tricosporonose/tratamento farmacológico , Tricosporonose/microbiologia , Leucemia Megacarioblástica Aguda/complicações , Leucemia Megacarioblástica Aguda/tratamento farmacológico , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/tratamento farmacológico , Eritema/complicações , Eritema/tratamento farmacológico
3.
Mycoses ; 67(1): e13668, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37907831

RESUMO

This study analyzes the clinical characteristics of patients diagnosed with White Piedra through a systematic review of cases in the literature. A sample of 131 subjects was considered, of which 91.6% were female and most were 18 years of age or younger. Most studies were conducted in Brazil, followed by India, and Mexico. The most common etiologic agent found was Trichosporon spp (34.3%). Most affected patients were asymptomatic (94.6%) and predisposing factors included long hair, use of a hair band or hair accessories, and wet hair. The most common clinical feature was the presence of nodules. The evaluation of treatment effectiveness was hindered by the scarcity of follow-up information in the majority of the studies. It is concluded that White Piedra infection is more common in young women and is associated with hair-related factors.


Assuntos
Piedra , Trichosporon , Humanos , Feminino , Masculino , Piedra/diagnóstico , Piedra/tratamento farmacológico , Piedra/etiologia , Cabelo , Brasil/epidemiologia , México/epidemiologia
5.
Eur J Clin Microbiol Infect Dis ; 43(3): 597-604, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38103075

RESUMO

Fungal infections due to Apiotrichum mycotoxinivorans are clinically rare. Here, we report a case of invasive blood and cerebrospinal fluid infection by Apiotrichum mycotoxinivorans in a girl with B-cell acute lymphoblastic leukemia. This is the first report of the isolation of Apiotrichum mycotoxinivorans from human cerebrospinal fluid. MRI features of meningitis caused by this fungus are presented. Three small isoquinoline alkaloids inhibited the growth of this rare fungus in vitro, providing a starting point for the application of natural products to treat this highly fatal fungal infection. Our case presentation confirms Apiotrichum mycotoxinivorans as a potential emerging pathogen in patients with hematological malignancy undergoing chemotherapy.


Assuntos
Basidiomycota , Micoses , Trichosporon , Feminino , Humanos , Micoses/microbiologia , Líquido Cefalorraquidiano
6.
Diagn Microbiol Infect Dis ; 107(3): 116057, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37659120

RESUMO

Trichosporon asahii is an emerging opportunistic fungus that mainly causes fatal disseminated trichosporonosis, especially in immunocompromised patients. T. asahii infection has been reported in Thailand, but few studies of this fungus have been published. Therefore, this study investigated the genetic diversity of 51 clinical strains of T. asahii from urine samples in Thailand. We sequenced and characterized the beta-1-tubulin (TUB1), copper-exporting ATPase (ATP), phosphate carrier protein (PHCP), and topoisomerase-1 (TOP1) genes. In addition, intergenic spacer 1 (IGS1) sequences from our previous studies were investigated. The numbers of haplotypes were 3, 3, 2, 2, and 2 for IGS1, TUB1, ATP, PHCP, and TOP1, respectively. The results suggested a relatively low level of genetic diversity among the strains. The findings illustrated that IGS1, TUB1, ATP, PHCP, and TOP1 can be collectively used as an alternative molecular typing tool for investigating the population diversity and structure of T. asahii.


Assuntos
Trichosporon , Tricosporonose , Humanos , Trichosporon/genética , Genótipo , DNA Fúngico/genética , Tricosporonose/microbiologia , Trifosfato de Adenosina , Antifúngicos/farmacologia
7.
Indian J Med Microbiol ; 45: 100390, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37573054

RESUMO

OBJECTIVES: Molecular genotyping of Trichosporon species using intergenic spacer region (IGS-1) sequencing and antifungal drug susceptibility testing of T. asahii clinical isolates from Indian patients. MATERIALS AND METHODS: Fifty-five Trichosporon strains were characterized using IGS-1 sequencing from 2006 to 2018 and tested against 5 antifungals using CLSI M27-A3 guidelines. RESULTS: In this study, broad-spectrum antibiotics with steroids, catheters, and ICU stays were major underlying risk factors. These cases were most commonly associated with diabetes (type-2), chronic obstructive pulmonary disease, and hypertension. Out of fifty-five isolates, 47 (85%) were identified as T. asahii, and the remaining 6 were T. inkin (11%) and 2 were Cutaneotrichosporon dermatis (3.6%). The most common genotype of T. asahii was G3 (22; 49%) subsequently G4 (12; 23%), G1 (8; 17%), and G7 (2; 4%). One new genotype of T asahii was found in addition to the fifteen already known genotypes. Indian T. asahii isolates showed a low level of amphotericin B (range 0.06-4 â€‹mg/l) resistance but relatively higher in fluconazole (range 0.25-64 â€‹mg/l). Although, comparatively low MIC ranges were found in the case of voriconazole (0.03-1 â€‹mg/l), posaconazole (0.06-1 â€‹mg/l) and itraconazole (0.06-1 â€‹mg/l). Voriconazole appeared to be the most active drug in T. asahii isolates. The MICs for all the drugs were comparatively lower in the case of non-Trichosporon asahii strains. CONCLUSION: T. asahii was the most common Trichosporon isolate. Speciation is necessary for optimal antifungal therapy. Voriconazole-based treatment, Steroids, removal of catheters and control of underlying conditions results in positive outcomes.


Assuntos
Mycobacterium tuberculosis , Trichosporon , Tricosporonose , Humanos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Trichosporon/genética , Voriconazol/farmacologia , Voriconazol/uso terapêutico , DNA Intergênico/genética , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/genética , Esteroides , Tricosporonose/tratamento farmacológico
8.
Mycoses ; 66(11): 992-1002, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37515448

RESUMO

BACKGROUND: Trichosporon is an emerging yeast that causes invasive infections in immunocompromised patients experiencing prolonged hospitalisation, indwelling venous catheters and neutropenia. METHODS: This retrospective observational cohort study analysed invasive Trichosporon infections (ITIs) occurring between January 2005 and December 2022 at three tertiary hospitals and compared the clinical characteristics and prognostic factors of ITIs caused by Trichosporon asahii and non-T. asahii spp. After evaluating 1067 clinical isolates, we identified 46 patients with proven ITIs, defined as cases in which Trichosporon was isolated from blood, cerebrospinal fluid, or sterile tissues. RESULTS: The patients were separated into T. asahii and non-T. asahii groups containing 25 and 21 patients, respectively, all of which except one were immunocompromised. During this period, both the number of clinical isolates and patients with ITIs (mainly T. asahii) increased; whereas, cases involving non-T. asahii spp. decreased. Compared with the non-T. asahii group, the T. asahii group had more patients with multiple catheters (84% vs. 33%, p = .001) and those receiving renal replacement therapy (48% vs. 14%, p = .005). The all-cause 28-day mortality rate after ITI in the T. asahii group (44%) was significantly higher than in the non-T. asahii group (10%, Log-rank p = .014). The multivariate Cox regression model revealed that T. asahii (reference, non-T. asahii spp.; aHR = 4.3; 95% CI = 1.2-15.2, p = .024) and neutropenia for 5 days or more (aHR = 2.2, 95% CI = 1.5-3.6, p = .035) were independent factors in the 28-day mortality after ITI. CONCLUSION: The proven ITIs due to T. asahii produced more unfavourable outcomes compared with ITIs caused by non-T. asahii spp.


Assuntos
Neutropenia , Trichosporon , Tricosporonose , Humanos , Tricosporonose/tratamento farmacológico , Antifúngicos/uso terapêutico , Estudos Retrospectivos , Neutropenia/tratamento farmacológico
9.
J Vet Diagn Invest ; 35(5): 559-562, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37387318

RESUMO

Two adult mixed-breed ewes were presented with a 2-wk history of upper respiratory disease. Both animals were depressed, with bilateral serosanguineous nasal discharge and harsh bronchovesicular sounds accompanied by crackles and wheezes on auscultation. One animal was recumbent and was euthanized at presentation. The other animal with similar signs, as well as exophthalmos, was euthanized because of a mass in the nasal passages. On autopsy, severe pyogranulomatous and necrotizing ethmoidal rhinitis with focal pyogranulomatous pneumonia was diagnosed in both animals. An intralesional fungal organism was identified in the nares and lungs of both animals. The organism could not be isolated via fungal culture but was identified as Trichosporon sp. by a PCR assay. Trichosporon spp. are rarely associated with disease in veterinary medicine. This ubiquitous fungus might cause disease following trauma to the nasal passages or secondary to immunocompromise.


Assuntos
Pneumonia , Doenças dos Ovinos , Trichosporon , Tricosporonose , Feminino , Animais , Ovinos , Tricosporonose/diagnóstico , Tricosporonose/microbiologia , Tricosporonose/veterinária , Pulmão , Pneumonia/veterinária , Doenças dos Ovinos/diagnóstico
10.
Bioresour Technol ; 384: 129345, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37348570

RESUMO

Co-production of single cell protein (SCP) and lipid from lignocellulose-derived carbohydrates and inorganic ammonia offers a promising alternative for poultry or aquaculture feeds. An engineered oleaginous yeast Trichosporon cutaneum MP11 showed great potential for producing SCP and lipid from wheat straw and ammonia sulfate with minimum nutrient input. Trichosporon cutaneum MP11 showed stronger SCP and lipid fermentability using dry acid pretreated and biodetoxified wheat straw than using pure sugars. The residual ammonium sulfate in fermentation broth was recycled up to five times, resulting in ∼70% of nitrogen fixation into SCP. The overall yield of SCP and lipid from lignocellulose-derived sugars was 0.15 g/g and 0.11 g/g, respectively. This translates to the production of one ton of SCP (0.56 ton) and lipid (0.44 ton) from 6.6 tons of wheat straw, or one ton of SCP and lipid containing yeast cells (dry) from 4.8 tons of wheat straw.


Assuntos
Amônia , Trichosporon , Amônia/metabolismo , Trichosporon/metabolismo , Carboidratos , Fermentação , Cloreto de Sódio/metabolismo , Açúcares/metabolismo , Lipídeos
11.
Biofouling ; 39(2): 218-230, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-37122169

RESUMO

Trichosporon spp. are emerging opportunistic fungi associated with invasive infections, especially in patients with haematological malignancies. The present study investigated the in vitro inhibition of efflux pumps by promethazine (PMZ) as a strategy to control T. asahii and T. inkin. Planktonic cells were evaluated for antifungal susceptibility to PMZ, as well as inhibition of efflux. The effect of PMZ was also studied in Trichosporon biofilms. PMZ inhibited T. asahii and T. inkin planktonic cells at concentrations ranging from 32 to 256 µg ml-1. Subinhibitory concentrations of PMZ inhibited efflux activity in Trichosporon. Biofilms were completely eradicated by PMZ. PMZ potentiated the action of antifungals, affected the morphology, changed the amount of carbohydrates and proteins and reduced the amount of persister cells inside biofilms. The results showed indirect evidences of the occurrence of efflux pumps in Trichosporon and opens a perspective for the use of this target in the control of trichosporonosis.


Assuntos
Antifúngicos , Trichosporon , Humanos , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Prometazina/farmacologia , Prometazina/metabolismo , Biofilmes , Plâncton , Testes de Sensibilidade Microbiana
12.
Biotechnol J ; 18(8): e2300091, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37182226

RESUMO

Accumulation of intracellular lipid bodies in oleaginous yeast cells is highly restricted by their natural intracellular space. Here we show a cellulase mediated adaptive evolution with ultra-centrifugation fractionation of oleaginous yeast Trichosporon cutaneum to obtain the favorable cell structure for lipid accumulation. Cellulase was added to the wheat straw hydrolysate during long-term adaptive evolution for disruption of cell wall integrity of T. cutaneum cells. The cellulase, together with ultracentrifugation force, triggered multiple mutations and transcriptional expression changes of the functional genes associated with cell wall integrity and lipid synthesis metabolism. The fractionated mutant T. cutaneum YY52 demonstrated the heavily weakened cell wall and high lipid accumulation by the super-large expanded spindle cells (two orders of magnitude greater than the parental). A record-high lipid production by T. cutaneum YY52 was achieved (55.4 ± 0.5 g L-1 from wheat straw and 58.4 ± 0.1 g L-1 from corn stover). This study not only obtained an oleaginous yeast strain with industrial application potential for lipid production but also provided a new method for generation of mutant cells with high intracellular metabolite accumulation.


Assuntos
Celulase , Trichosporon , Trichosporon/genética , Trichosporon/metabolismo , Celulase/genética , Celulase/metabolismo , Lipídeos , Mutação
13.
Microbiol Spectr ; 11(3): e0090723, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37199655

RESUMO

Trichosporon asahii is an emerging opportunistic pathogen that causes potentially fatal disseminated trichosporonosis. The global prevalence of coronavirus disease 2019 (COVID-19) poses an increasing fungal infection burden caused by T. asahii. Allicin is the main biologically active component with broad-spectrum antimicrobial activity in garlic. In this study, we performed an in-depth analysis of the antifungal characteristics of allicin against T. asahii based on physiological, cytological, and transcriptomic assessments. In vitro, allicin inhibited the growth of T. asahii planktonic cells and biofilm cells significantly. In vivo, allicin improved the mean survival time of mice with systemic trichosporonosis and reduced tissue fungal burden. Electron microscopy observations clearly demonstrated damage to T. asahii cell morphology and ultrastructure caused by allicin. Furthermore, allicin increased intracellular reactive oxygen species (ROS) accumulation, leading to oxidative stress damage in T. asahii cells. Transcriptome analysis showed that allicin treatment disturbed the biosynthesis of cell membrane and cell wall, glucose catabolism, and oxidative stress. The overexpression of multiple antioxidant enzymes and transporters may also place an additional burden on cells, causing them to collapse. Our findings shed new light on the potential of allicin as an alternative treatment strategy for trichosporonosis. IMPORTANCE Systemic infection caused by T. asahii has recently been recognized as an important cause of mortality in hospitalized COVID-19 patients. Invasive trichosporonosis remains a significant challenge for clinicians, due to the limited therapeutic options. The present work suggests that allicin holds great potential as a therapeutic candidate for T. asahii infection. Allicin demonstrated potent in vitro antifungal activity and potential in vivo protective effects. In addition, transcriptome sequencing provided valuable insights into the antifungal effects of allicin.


Assuntos
COVID-19 , Trichosporon , Tricosporonose , Animais , Camundongos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Tricosporonose/tratamento farmacológico , Tricosporonose/microbiologia , Trichosporon/fisiologia , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico
14.
Int J Mol Sci ; 24(10)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37240199

RESUMO

Trichosporon asahii is an opportunistic pathogen that can cause severe or even fatal infections in patients with low immune function. sPLA2 plays different roles in different fungi and is also related to fungal drug resistance. However, the mechanism underlying its drug resistance to azoles has not yet been reported in T. asahii. Therefore, we investigated the drug resistance of T. asahii PLA2 (TaPLA2) by constructing overexpressing mutant strains (TaPLA2OE). TaPLA2OE was generated by homologous recombination of the recombinant vector pEGFP-N1-TaPLA2, induced by the CMV promoter, with Agrobacterium tumefaciens. The structure of the protein was found to be typical of sPLA2, and it belongs to the phospholipase A2_3 superfamily. TaPLA2OE enhanced antifungal drug resistance by upregulating the expression of effector genes and increasing the number of arthrospores to promote biofilm formation. TaPLA2OE was highly sensitive to sodium dodecyl sulfate and Congo red, indicating impaired cell wall integrity due to downregulation of chitin synthesis or degradation genes, which can indirectly affect fungal resistance. In conclusion, TaPLA2 overexpression enhanced the resistance to azoles of T. asahii by enhancing drug efflux and biofilm formation and upregulating HOG-MAPK pathway genes; therefore, it has promising research prospects.


Assuntos
Azóis , Trichosporon , Humanos , Azóis/farmacologia , Antifúngicos/farmacologia , Trichosporon/genética , Farmacorresistência Fúngica/genética , Biofilmes
15.
Med Mycol J ; 64(2): 29-36, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37258132

RESUMO

Trichosporon asahii is an invasive pathogenic yeast that infects immunocompromised hosts. Several virulence factors contribute to the fungal infection; however, the factors that contribute to the occurrence of T. asahii infections remain unclear. Since adhesins are typical virulence factors reported for pathogenic fungi, we looked for host proteins that interact with the T. asahii cell surface. T. asahii and Candida albicans were used for screening using a pull-down assay with fetal bovine serum. Serum albumin and elongation factor 2 were identified as the yeast-binding serum proteins. Additionally, we investigated the interactions of the cell surface-associated molecules (CSM) of T. asahii with vitronectin (VTN), fibronectin, fetuin-A, and alpha-1antitrypsin (AAT). The surface plasmon resonance (SPR) method was used to examine the interaction between CSM and human proteins. On the other hand, the pull-down assay was used to examine the interaction between human proteins and the T. asahii cell surface. Serum albumin, AAT, and VTN were found to interact with T. asahii in both SPR and pull-down assays. This study identified several proteins that interact with T. asahii, suggesting that these proteins play a role in infection mechanisms.


Assuntos
Basidiomycota , Trichosporon , Tricosporonose , Humanos , Proteínas Fúngicas , Albumina Sérica , Fatores de Virulência , Antifúngicos , Tricosporonose/microbiologia
16.
Microbiol Spectr ; 11(3): e0424222, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37102973

RESUMO

Fungal dimorphism involves two morphologies: a unicellular yeast cell and a multicellular hyphal form. Invasion of hyphae into human cells causes severe opportunistic infections. The transition between yeast and hyphal forms is associated with the virulence of fungi; however, the mechanism is poorly understood. Therefore, we aimed to identify factors that induce hyphal growth of Trichosporon asahii, a dimorphic basidiomycete that causes trichosporonosis. T. asahii showed poor growth and formed small cells containing large lipid droplets and fragmented mitochondria when cultivated for 16 h in a nutrient-deficient liquid medium. However, these phenotypes were suppressed via the addition of yeast nitrogen base. When T. asahii cells were cultivated in the presence of different compounds present in the yeast nitrogen base, we found that magnesium sulfate was a key factor for inducing cell elongation, and its addition dramatically restored hyphal growth in T. asahii. In T. asahii hyphae, vacuoles were enlarged, the size of lipid droplets was decreased, and mitochondria were distributed throughout the cell cytoplasm and adjacent to the cell walls. Additionally, hyphal growth was disrupted due to treatment with an actin inhibitor. The actin inhibitor latrunculin A disrupted the mitochondrial distribution even in hyphal cells. Furthermore, magnesium sulfate treatment accelerated hyphal growth in T. asahii for 72 h when the cells were cultivated in a nutrient-deficient liquid medium. Collectively, our results suggest that an increase in magnesium levels triggers the transition from the yeast to hyphal form in T. asahii. These findings will support studies on the pathogenesis of fungi and aid in developing treatments. IMPORTANCE Understanding the mechanism underlying fungal dimorphism is crucial to discern its invasion into human cells. Invasion is caused by the hyphal form rather than the yeast form; therefore, it is important to understand the mechanism of transition from the yeast to hyphal form. To study the transition mechanism, we utilized Trichosporon asahii, a dimorphic basidiomycete that causes severe trichosporonosis since there are fewer studies on T. asahii than on ascomycetes. This study suggests that an increase in Mg2+, the most abundant mineral in living cells, triggers growth of filamentous hyphae and increases the distribution of mitochondria throughout the cell cytoplasm and adjacent to the cell walls in T. asahii. Understanding the mechanism of hyphal growth triggered by Mg2+ increase will provide a model system to explore fungal pathogenicity in the future.


Assuntos
Basidiomycota , Trichosporon , Tricosporonose , Humanos , Trichosporon/genética , Magnésio , Saccharomyces cerevisiae , Tricosporonose/microbiologia , Sulfato de Magnésio , Actinas , Nitrogênio , Antifúngicos/farmacologia
17.
Med Mycol ; 61(3)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36807459

RESUMO

Trichosporonosis corresponds to a systemic fungal disease that leads to high mortality rates and is frequently associated with medical devices. It affects immunosuppressed patients in particular and is strongly linked to acquired human immunodeficiency, organ and tissue transplants, and malignant hematologic diseases such as leukemia and lymphomas. Trichosporon infections have been increasingly reported worldwide; however, little information is available either about their characteristics or the causative microorganism. Thus, the aims of the present study were: to investigate 59 yeasts of the genus Trichosporon by verifying the biofilm formation capacity of isolates; to analyze the susceptibility patterns of planktonic cells against the antifungals fluconazole, itraconazole, amphotericin-B, voriconazole, and caspofungin by comparing European Committee for Antimicrobial Susceptibility Testing (EUCAST) broth microdilution technique with the commercial method Etest; and to assess the susceptibility patterns of biofilm cells (sessile) against the same antifungals through broth microdilution. The ability to form biofilm on the surface of polystyrene plates was noted for all isolates, and 54.3% of samples were considered strong producers. Comparison between the antifungal susceptibility techniques evidenced that Etest showed higher and discordant minimum inhibitory concentrations (MICs) from those obtained by the microdilution method, especially for fluconazole, itraconazole, and caspofungin. Considering the susceptibility of biofilms, most species had high MIC50 and MIC90 against the tested antifungals, showing 4-to-66-fold higher concentrations for amphotericin B and 2-to-33-fold greater concentrations for caspofungin. These results highlight the importance of further studies with Trichosporon spp. for comparison between laboratory findings and in vivo response, considering both the susceptibility tests and the behavior of biofilm cells against drugs.


This study investigated 59 isolates of the medically important yeast Trichosporon in relation to their ability to form biofilms and the susceptibility of biofilms to antifungal agents. All isolates were able to produce biofilms and biofilms showed lower antifungal susceptibility.


Assuntos
Trichosporon , Tricosporonose , Humanos , Animais , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Fluconazol/farmacologia , Caspofungina , Itraconazol , Anfotericina B/farmacologia , Tricosporonose/microbiologia , Tricosporonose/veterinária , Biofilmes , Testes de Sensibilidade Microbiana/veterinária
18.
Mycoses ; 66(6): 467-476, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36680377

RESUMO

BACKGROUND: Trichosporon asahii is an opportunistic pathogenic yeast-like fungus. Phospholipase B1 (PLB1) is an important virulence factor of pathogenic fungi such as Candida albicans and Cryptococcus neoformans, and there are few studies on the role of PLB1 in the pathogenicity of T. asahii. OBJECTIVES: To investigate the role of PLB1 in the pathogenicity of T. asahii. METHODS: A strain with low secretion of PLB1 (4848) was screened, a PLB1 overexpression strain (PLB1OX ) was constructed, and the differences in histopathology, fungal load of organ, survival time of mice, the levels of IL-6, IL-10, TNF-α, and GM-GSF in the serum and organs caused by the two strains were compared. RESULTS: Histopathology showed that spores and hyphae were observed in both groups, and PLB1OX led to more fungal invasion. The fungal loads in the kidney, lung, spleen and liver in the PLB1OX group were significantly higher than those in the 4848 group, and the survival time of mice was significantly lower than that in the 4848 group. The levels of TNF-α in the serum, liver, spleen, lung and kidney of the PLB1OX group were lower than those of the 4848 group, while the level of IL-10 in the serum was higher than that of the 4848 group. CONCLUSIONS: These results suggest that PLB1 can enhance the invasive function of T. asahii and affect the secretion of TNF-α and IL-10 which may affect the host antifungal immune response, providing evidence that PLB1 plays a role in the pathogenic infection of T. asahii.


Assuntos
Interleucina-10 , Trichosporon , Animais , Camundongos , Fosfolipases , Trichosporon/genética , Fator de Necrose Tumoral alfa , Virulência , Lisofosfolipase/metabolismo
19.
J Antimicrob Chemother ; 78(3): 817-822, 2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36702754

RESUMO

OBJECTIVES: To evaluate the in vitro activity of isavuconazole on 154 clinical and reference strains of Trichosporon asahii, Trichosporon asteroides, Trichosporon coremiiforme, Trichosporon faecale and Trichosporon inkin by using the EUCAST broth microdilution method (BMD) and Liofilchem MIC Test Strips (MTS). METHODS: Antifungal susceptibility testing for isavuconazole, fluconazole, voriconazole and posaconazole was assessed by EUCAST E.DEF 7.3.2. MIC values of isavuconazole obtained by BMD after 48 h of incubation were compared with MTS MICs after 24 and 48 h of incubation. RESULTS: T. asahii and T. asteroides showed the highest isavuconazole MIC90 values (0.5 mg/L). In clinical isolates, T. asahii exhibited the highest MIC90 values (0.5 mg/L) compared with non-T. asahii (0.06-0.25 mg/L). The five non-WT T. asahii isolates for fluconazole, voriconazole and posaconazole also exhibited high MICs of isavuconazole (≥0.5 mg/L). A better correlation between MTS and BMD MICs was observed after 24 h incubation for all species tested. MTS measurements performed at 48 h increased by at least 122% the number of isolates with >2 dilutions compared with the standard method. CONCLUSIONS: Isavuconazole exhibited variable in vitro activity among the Trichosporon species tested, showing higher or equal MICs than the other azoles. The five non-WT T. asahii clinical isolates tested also exhibited high isavuconazole MICs, suggesting the occurrence of triazole cross-resistance. Our MTS data indicate that there is no advantage in extended reading time for MTS from 24 to 48 h for Trichosporon yeasts.


Assuntos
Antifúngicos , Trichosporon , Voriconazol , Fluconazol , Triazóis , Testes de Sensibilidade Microbiana
20.
Mycoses ; 66(5): 430-440, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36564594

RESUMO

BACKGROUND: The Trichosporonaceae family comprises a large number of basidiomycetes widely distributed in nature. Some of its members, especially Trichosporon asahii, have the ability to cause human infections. This ability is related to a series of virulence factors, which include lytic enzymes production, biofilm formation, resistance to oxidising agents, melanin and glucuronoxylomannan in the cell wall, metabolic plasticity and phenotypic switching. The last two are poorly addressed within human pathogenic Trichosporonaceae. OBJECTIVE: These factors were herein studied to contribute with the knowledge of these emerging pathogens and to uncover mechanisms that would explain the higher frequency of T. asahii in human infections. METHODS: We included 79 clinical isolates phenotypically identified as Trichosporon spp. and performed their molecular identification. Lactate and N-acetyl glucosamine were the carbon sources of metabolic plasticity studies. Morphologically altered colonies after subcultures and incubation at 37°C indicated phenotypic switching. RESULTS AND CONCLUSION: The predominant species was T. asahii (n = 65), followed by Trichosporon inkin (n = 4), Apiotrichum montevideense (n = 3), Trichosporon japonicum (n = 2), Trichosporon faecale (n = 2), Cutaneotrichosporon debeurmannianum (n = 1), Trichosporon ovoides (n = 1) and Cutaneotrichosporon arboriforme (n = 1). T. asahii isolates had statistically higher growth on lactate and N-acetylglucosamine and on glucose during the first 72 h of culture. T. asahii, T. inkin and T. japonicum isolates were able to perform phenotypic switching. These results expand the virulence knowledge of Trichosporonaceae members and point for a role for metabolic plasticity and phenotypic switching on the trichosporonosis pathogenesis.


Assuntos
Basidiomycota , Trichosporon , Tricosporonose , Humanos , Antifúngicos , Trichosporon/genética , Virulência , Adaptação Fisiológica , Lactatos
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