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1.
Emerg Infect Dis ; 30(11): 2323-2332, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39447155

RESUMEN

Fluconazole-resistant clade 4 Candida tropicalis causing candidemia in humans has been detected in tropical/subtropical areas, including those in China, Singapore, and Australia. We analyzed 704 individual yeasts isolated from fruits, soil, water, and farmers at 80 orchards in Taiwan. The most common pathogenic yeast species among 251 isolates recovered from farmers were Candida albicans (14.7%) and C. parapsilosis (11.6%). In contrast, C. tropicalis (13.0%), C. palmioleophila (6.6%), and Pichia kudriavzevii (6.0%) were prevalent among 453 environmental isolates. Approximately 18.6% (11/59) of C. tropicalis from the environment were resistant to fluconazole, and 81.8% (9/11) of those belonged to the clade 4 genotype. C. tropicalis susceptibility to fluconazole correlated with susceptibilities to the agricultural azole fungicides, difenoconazole, tebuconazole, and triadimenol. Tandem gene duplications of mutated ERG11 contributed to azole resistance. Agriculture environments are a reservoir for azole-resistant C. tropicalis; discontinuing agricultural use of azoles might reduce emergence of azole-resistant Candida spp. strains in humans.


Asunto(s)
Antifúngicos , Azoles , Candida tropicalis , Candidemia , Farmacorresistencia Fúngica , Genotipo , Pruebas de Sensibilidad Microbiana , Humanos , Taiwán/epidemiología , Farmacorresistencia Fúngica/genética , Candidemia/microbiología , Candidemia/epidemiología , Candida tropicalis/efectos de los fármacos , Candida tropicalis/genética , Candida tropicalis/aislamiento & purificación , Antifúngicos/farmacología , Azoles/farmacología , Fluconazol/farmacología
2.
BMC Res Notes ; 17(1): 321, 2024 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-39449135

RESUMEN

BACKGROUND: Candida africana is an emergent variant that has been listed as a new species or variety within the Candida albicans complex since 2001. It has a worldwide intra-albicans complex pooled prevalence of 1.67% and varies between 0 and 8% depending on geographical region. We present the results of a pilot study on its prevalence in Uganda. METHODOLOGY: We conducted a cross-sectional study between March and June 2023. We recruited 4 pregnant women from Mulago Specialized Women and Neonatal Hospital, 102 from Kawempe National Referral Hospital, and 48 from Sebbi Hospital. Vaginal swabs were tested using microscopy, culture and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF). RESULTS: The prevalence of C. africana was zero. Out of the 103 isolates, the majority (81.553%) were identified as Candida albicans, followed by Nakeseomyces glabrata (13.592%) and Pichia kudriavzevii (1.942%). Cyberlindnera jadinii, Candida tropicalis, and Candida parapsilosis each accounted for 0.971% of the isolates. CONCLUSION: The prevalence of C. africana in Uganda is zero. However, large-scale cross-sectional studies, including studies involving the collection of vaginal samples from both urban and rural settings in Uganda and the use of both MALDI-TOF- and PCR-based laboratory methods, are needed to fully describe the public health burden of C. africana infections.


Asunto(s)
Candida , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Humanos , Femenino , Uganda/epidemiología , Proyectos Piloto , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Estudios Transversales , Embarazo , Candida/aislamiento & purificación , Candida/clasificación , Adulto , Prevalencia , Vagina/microbiología , Adulto Joven , Candida albicans/aislamiento & purificación , Candida tropicalis/aislamiento & purificación , Pichia
3.
BMC Microbiol ; 24(1): 428, 2024 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-39443857

RESUMEN

Candida tropicalis (C. tropicalis) is a zoonotic pathogen that is widespread in the environment and in recent years an increasing number of dairy cows have been infected with the fungus causing mastitis in cows.In this study, 37 milk samples from the udders of cows with clinical mastitis were collected from a dairy farm in Guangxi Province, China, from which C. tropicalis was isolated and identified, and then the isolated fungi were subjected to genome frame map sequencing, genome functional analysis as well as comparative genome analysis of the sequencing results, and combined with the virulence test of the fungi and drug sensitivity test of the fungi determined in infected mice, the resistance genes and pathogenicity of the fungi were Analysis of resistance genes and pathogenicity.Our study results revealed the isolation and characterisation of C. tropicalis from diseased cows, with a genome length of approximately 14.27 Mb. Functional annotation of the genome identified 4068 genes associated with C. tropicalis. The strain exhibited a chemoresistance mutation in the gene cyp51,a virulence-enhancing mutation in the gene VTC4, and mutations in genes linked to drug resistance. Pathogenicity tests demonstrated that C. tropicalis could induce damage to the internal organs of mice, leading to different levels of cyanosis in the abdominal cavity, white necrotic foci on the surface of internal organs, lung hemorrhage, and enlargement of the spleen and thymus.Histological sections also revealed varying degrees of hemorrhage and degenerative changes in the cells of different organs in the mice. Drug sensitivity tests showed that the fungus was highly sensitive to nystatin and ketoconazole, moderately sensitive to amphotericin B, and insensitive to antibiotics such as itraconazole, gentamicin, and penicillin. In conclusion, C. tropicalis isolated from dairy cows in the Guangxi region in this study was pathogenic and resistant to azoles such as itraconazole and fluconazole, and this study provides a theoretical basis for the further screening of novel resistance genes in C. tropicalis, as well as providing a certain reference for the drugs used for the treatment of fungal cow mastitis in this region.


Asunto(s)
Antifúngicos , Candida tropicalis , Candidiasis , Farmacorresistencia Fúngica , Mastitis Bovina , Animales , Bovinos , Femenino , Candida tropicalis/genética , Candida tropicalis/efectos de los fármacos , Candida tropicalis/patogenicidad , Candida tropicalis/aislamiento & purificación , Mastitis Bovina/microbiología , Farmacorresistencia Fúngica/genética , Ratones , Antifúngicos/farmacología , China , Virulencia/genética , Candidiasis/microbiología , Candidiasis/veterinaria , Genoma Fúngico , Leche/microbiología , Pruebas de Sensibilidad Microbiana
4.
FEMS Yeast Res ; 242024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-39435647

RESUMEN

Candida tropicalis is a leading cause of nonalbicans candidemia in tropical/subtropical areas and a predominant genotype of azole-resistant C. tropicalis clinical isolates belongs to clade 4. The aim of this study was to reveal markers for rapidly identifying the predominant azole-resistant C. tropicalis genotype. We analysed XYR1, one of the six genes used in the multilocus sequence typing analysis, and SNQ2, an ATP-binding cassette transporter in 281 C. tropicalis, including 120 and 161 from Taiwan and global areas, respectively. Intriguingly, the first 4-mer of codon sequences ATRA of CTRG_05978 (96/119 versus 21/162, P < .001, at phi = 0. 679) and the SNQ2 A2977G resulting in amino acid I993V alternation (105/118 versus 12/163, P < .001, at phi = 0.81) was significantly associated with the clade 4 genotype. The sensitivity and specificity of the clade 4 genotype detection with a combination of SNPs of CTRG_05978 and SNQ2 were 0.812 and 0.994, respectively, at phi = 0.838. Furthermore, we successfully established a TaqMan SNP genotyping assay to identify the clade 4 genotype. Our findings suggest that to improve the management of C. tropicalis infections, rapidly identifying azole-resistant C. tropicalis by detecting SNPs of CTRG_05978 and SNQ2 is promising.


Asunto(s)
Antifúngicos , Azoles , Candida tropicalis , Farmacorresistencia Fúngica , Genotipo , Candida tropicalis/genética , Candida tropicalis/efectos de los fármacos , Candida tropicalis/aislamiento & purificación , Azoles/farmacología , Farmacorresistencia Fúngica/genética , Antifúngicos/farmacología , Taiwán , Humanos , Sensibilidad y Especificidad , Polimorfismo de Nucleótido Simple
5.
Microb Pathog ; 196: 106948, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39306052

RESUMEN

Patients with orofacial clefts are more likely to develop oral fungal diseases due to anatomo-physiological changes and surgical rehabilitation treatment. This case-series study evaluated the genetic diversity and dynamics of oral colonization and spread of C. albicans and C. tropicalis in four patients with orofacial clefts, from the time of hospital admission, perioperative and outpatient follow-up, with specialized physician. Candida biotypes previously identified by CHROMagar Candida and PCR methods were studied by MALDI-TOF MS assays and clustering analyses. Possible correlations with pathogenicity characteristics were observed, including production of hydrolytic exoenzymes and the antifungal sensitivity profiles. Amphotericin B-sensitive and fluconazole-resistant (low frequency) C. tropicalis and C. albicans, including clinically compatible MIC of nystatin, were found in the oral cavity of these patients. Clusters of isolates revealed phenomena of (i) elimination in the operative phase, (ii) maintenance or (iii) acquisition of oral C. tropicalis in the perioperative period and specialized outpatient and medical follow-up. For C. albicans, these phenomena included (i) elimination in the operative phase, (ii) acquisition in the operative phase and propagation from the hospital environment, and (iii) maintenance during hospitalization and operative phase. Amphotericin B and nystatin were shown to be effective in cases of clinical treatment and/or prophylaxis, especially considering the pre-existence of fluconazole-resistant strains. This study confirmed the phenomena of septic maintenance, septic neocolonization and septic elimination involving the opportunistic pathogens. MALDI-TOF MS associated with clustering analysis may assist the monitoring of clinical isolates or groups of epidemiologically important microbial strains in the hospital setting.


Asunto(s)
Anfotericina B , Antifúngicos , Candida albicans , Candida tropicalis , Farmacorresistencia Fúngica , Genotipo , Pruebas de Sensibilidad Microbiana , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Humanos , Candida tropicalis/efectos de los fármacos , Candida tropicalis/aislamiento & purificación , Candida tropicalis/genética , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Candida albicans/genética , Candida albicans/efectos de los fármacos , Candida albicans/aislamiento & purificación , Anfotericina B/farmacología , Anfotericina B/uso terapéutico , Masculino , Femenino , Boca/microbiología , Niño , Fluconazol/farmacología , Fluconazol/uso terapéutico , Candidiasis Bucal/microbiología , Nistatina/farmacología , Nistatina/uso terapéutico , Técnicas de Tipificación Micológica , Fisura del Paladar/cirugía , Labio Leporino/cirugía , Adolescente , Análisis por Conglomerados , Preescolar
6.
J Pak Med Assoc ; 74(8): 1533-1537, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39160730

RESUMEN

Fungi rarely cause infective endocarditis but when they do, they are often associated with poor outcomes. Candida tropicalis accounts for only 10% of Candida endocarditis cases. A case of a 30-year-old male with a history of intravenous drug abuse was reported to the emergency department in August, 2021 with right-sided leg pain and fever for 3 days. A trans-thoracic echocardiogram showed a vegetation on the aortic valve and a computed tomography angiogram showed complete nonopacification of the right-sided common iliac artery and the superficial femoral artery just distal to its branching of the right profunda femoris artery. An emergent right iliofemoral embolectomy was done. Candida tropicalis was isolated from tissue and blood cultures. The patient was successfully treated with aortic valve replacement and intravenous caspofungin. The other reported cases of Candida tropicalis were reviewed and findings were compared with those reported in patients with Candida albicans and Candida parapsilosis endocarditis.


Asunto(s)
Antifúngicos , Candida tropicalis , Candidiasis , Endocarditis , Humanos , Candida tropicalis/aislamiento & purificación , Masculino , Adulto , Antifúngicos/uso terapéutico , Candidiasis/diagnóstico , Candidiasis/microbiología , Candidiasis/tratamiento farmacológico , Endocarditis/microbiología , Endocarditis/diagnóstico , Endocarditis/tratamiento farmacológico , Caspofungina/uso terapéutico , Abuso de Sustancias por Vía Intravenosa/complicaciones , Implantación de Prótesis de Válvulas Cardíacas , Embolectomía/métodos , Válvula Aórtica/cirugía , Válvula Aórtica/microbiología , Válvula Aórtica/diagnóstico por imagen , Arteria Femoral/cirugía , Arteria Femoral/microbiología , Arteria Femoral/diagnóstico por imagen
7.
Med Mycol ; 62(6)2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38935905

RESUMEN

In response to the growing global burden of fungal infections with uncertain impact, the World Health Organization (WHO) established an Expert Group to identify priority fungal pathogens and establish the WHO Fungal Priority Pathogens List for future research. This systematic review aimed to evaluate the features and global impact of invasive candidiasis caused by Candida tropicalis. PubMed and Web of Science were searched for studies reporting on criteria of mortality, morbidity (defined as hospitalization and disability), drug resistance, preventability, yearly incidence, diagnostics, treatability, and distribution/emergence from 2011 to 2021. Thirty studies, encompassing 436 patients from 25 countries were included in the analysis. All-cause mortality due to invasive C. tropicalis infections was 55%-60%. Resistance rates to fluconazole, itraconazole, voriconazole and posaconazole up to 40%-80% were observed but C. tropicalis isolates showed low resistance rates to the echinocandins (0%-1%), amphotericin B (0%), and flucytosine (0%-4%). Leukaemia (odds ratio (OR) = 4.77) and chronic lung disease (OR = 2.62) were identified as risk factors for invasive infections. Incidence rates highlight the geographic variability and provide valuable context for understanding the global burden of C. tropicalis infections. C. tropicalis candidiasis is associated with high mortality rates and high rates of resistance to triazoles. To address this emerging threat, concerted efforts are needed to develop novel antifungal agents and therapeutic approaches tailored to C. tropicalis infections. Global surveillance studies could better inform the annual incidence rates, distribution and trends and allow informed evaluation of the global impact of C. tropicalis infections.


Asunto(s)
Antifúngicos , Candida tropicalis , Farmacorresistencia Fúngica , Organización Mundial de la Salud , Candida tropicalis/efectos de los fármacos , Candida tropicalis/aislamiento & purificación , Humanos , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Candidiasis Invasiva/epidemiología , Candidiasis Invasiva/microbiología , Candidiasis Invasiva/tratamiento farmacológico , Candidiasis Invasiva/mortalidad , Incidencia , Salud Global , Factores de Riesgo
8.
J Vet Cardiol ; 54: 1-6, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38838576

RESUMEN

A 6-month-old male intact miniature Australian Shepherd presented for surgical consultation for a previously diagnosed patent ductus arteriosus. Echocardiogram revealed a patent ductus arteriosus and a hyperechoic oscillating lesion within the main pulmonary artery. Blood cultures and eventual post-mortem examination revealed Candida tropicalis endocarditis. This case report highlights a rare case of fungal endocarditis with both echocardiographic and post-mortem findings.


Asunto(s)
Candida tropicalis , Candidiasis , Enfermedades de los Perros , Conducto Arterioso Permeable , Conducto Arterioso Permeable/veterinaria , Conducto Arterioso Permeable/complicaciones , Animales , Masculino , Candida tropicalis/aislamiento & purificación , Enfermedades de los Perros/microbiología , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/diagnóstico por imagen , Perros , Candidiasis/veterinaria , Candidiasis/diagnóstico , Endocarditis/veterinaria , Endocarditis/diagnóstico , Endocarditis/microbiología , Endocarditis/diagnóstico por imagen , Ecocardiografía/veterinaria , Resultado Fatal
9.
Saudi Med J ; 45(6): 606-616, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38830660

RESUMEN

OBJECTIVES: To assess the risk variables related to the types of candidemia for each patient, who was admitted into the intensive care unit regardless of the patient with or without complete diagnosis of COVID-19, during the period of March 2019 to December 2022. METHODS: The evaluation comparison of demographic and clinical data of COVID-19 positive and negative patients with candidemia confirmed in blood, 113 cases were assessed. Variables such as gender, age, age of hospitalization, history of hospitalization, concurrently infection, The acute physiology and chronic health evaluation-II scores, comorbidity checking, intubation, central venous catheter use, parenteral nutrition use, steroid use, antibiotic use, lymphopenia, and laboratory variables were evaluated. Candida species distribution, antifungal susceptibility in blood culture were determined. RESULTS: Coronavirus disease-19 was present in 62.8% of cases confirmed candidemia, and these cases were significantly different from COVID-19 negative cases. Significance was found in more intubation, central venous catheter use, parenteral nutrition, and steroid therapy in Group 2. There was no significance with species distribution and associated infection. In total, COVID-19 positive had higher hemoglobin, aspartate aminotransferase, alanine transaminase, and white blood cell levels, which may be associated with the possibility of revealing and controlling candidemia. CONCLUSION: Candida albicans and Candida Parapsilosis (C. parapsilosis) are the species seen in infected COVID-19 patients, while C. parapsilosis and Candida tropicalis are found in non-COVID-19 ones. Risk factors were intubation, parenteral nutrition, central venous catheter, and steroid in the COVID-19 group.


Asunto(s)
COVID-19 , Candida , Candidemia , Unidades de Cuidados Intensivos , Humanos , Candidemia/epidemiología , Factores de Riesgo , Masculino , Femenino , Unidades de Cuidados Intensivos/estadística & datos numéricos , COVID-19/complicaciones , COVID-19/epidemiología , Persona de Mediana Edad , Candida/aislamiento & purificación , Anciano , Adulto , Nutrición Parenteral , Candida albicans/aislamiento & purificación , Antifúngicos/uso terapéutico , SARS-CoV-2 , Candida tropicalis/aislamiento & purificación
10.
J Dermatol ; 51(10): 1364-1367, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38558228

RESUMEN

A Japanese male in his 30s with no underlying medical condition presented with painless nodules after being bitten by a dog during a stay in Bali, Indonesia, 7 years earlier. He was referred to our department with multiple ulcers, nodules, and masses on the right leg. The final diagnosis was mycetoma caused by Nocardia vulneris, which may have been exacerbated by colonization of Candida parapsilosis and C. tropicalis as these yeasts were isolated by culture from the tissue. Treatment with minocycline hydrochloride and sulfamethoxazole trimethoprim showed partial efficacy, but the addition of posaconazole achieved significant efficacy. This suggests that the surmised coexistence of pathogenic yeasts of lower virulency may have made mycetoma in this case intractable.


Asunto(s)
Antifúngicos , Micetoma , Nocardia , Humanos , Masculino , Micetoma/diagnóstico , Micetoma/microbiología , Micetoma/tratamiento farmacológico , Micetoma/patología , Antifúngicos/uso terapéutico , Adulto , Nocardia/aislamiento & purificación , Nocardiosis/diagnóstico , Nocardiosis/microbiología , Nocardiosis/tratamiento farmacológico , Animales , Combinación Trimetoprim y Sulfametoxazol/uso terapéutico , Triazoles/uso terapéutico , Candida parapsilosis/aislamiento & purificación , Perros , Resultado del Tratamiento , Candida tropicalis/aislamiento & purificación , Indonesia
11.
Pediatr Infect Dis J ; 40(8): 730-737, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-33872278

RESUMEN

BACKGROUND: We aimed to describe the epidemiology of candidemia among children in South Africa. METHODS: We conducted laboratory-based surveillance among neonates (≤28 days), infants (29 days to <1 year), children (1-11 years) and adolescents (12-17 years) with Candida species cultured from blood during 2012-2017. Identification and antifungal susceptibility of viable isolates were performed at a reference laboratory. We used multivariable logistic regression to determine the association between Candida parapsilosis candidemia and 30-day mortality among neonates. RESULTS: Of 2996 cases, neonates accounted for 49% (n = 1478), infants for 27% (n = 806), children for 20% (n = 589) and adolescents for 4% (n = 123). The incidence risk at tertiary public sector hospitals was 5.3 cases per 1000 pediatric admissions (range 0.39-119.1). Among 2943 cases with single-species infections, C. parapsilosis (42%) and Candida albicans (36%) were most common. Candida auris was among the 5 common species with an overall prevalence of 3% (n = 47). Fluconazole resistance was more common among C. parapsilosis (55% [724/1324]) versus other species (19% [334/1737]) (P < 0.001). Of those with known treatment (n = 1666), 35% received amphotericin B deoxycholate alone, 32% fluconazole alone and 30% amphotericin B deoxycholate with fluconazole. The overall 30-day in-hospital mortality was 38% (n = 586) and was highest among neonates (43% [323/752]) and adolescents (43% [28/65]). Compared with infection with other species, C. parapsilosis infection was associated with a reduced mortality among neonates (adjusted odds ratio 0.41, 95% confidence interval: 0.22-0.75, P = 0.004). CONCLUSIONS: Candidemia in this setting mainly affected neonates and infants and was characterized by fluconazole-resistant C. parapsilosis with no increased risk of death.


Asunto(s)
Candida/aislamiento & purificación , Candidemia/epidemiología , Niño Hospitalizado/estadística & datos numéricos , Adolescente , Cultivo de Sangre , Candida/clasificación , Candida albicans/aislamiento & purificación , Candida auris/aislamiento & purificación , Candida glabrata/aislamiento & purificación , Candida parapsilosis/aislamiento & purificación , Candida tropicalis/aislamiento & purificación , Niño , Preescolar , Farmacorresistencia Fúngica , Femenino , Humanos , Incidencia , Lactante , Mortalidad Infantil , Recién Nacido , Masculino , Sudáfrica/epidemiología , Centros de Atención Terciaria
12.
BMC Vet Res ; 17(1): 108, 2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33663504

RESUMEN

BACKGROUND: Candida is the common conditionally pathogenic fungus that infected human and animal clinically. C. tropicalis had been isolated from the skin and hair of healthy pigs, but with no report of fatal infection in gastrointestinal diseases. CASE PRESENTATION: In a pig farm in Henan Province of China, about 20 % of pregnant and postpartum sows suffered from severe gastrointestinal diseases, with a mortality rate higher than 60 % in the diseased animals. The sows had gastrointestinal symptoms such as blood in stool and vomiting. Necropsy revealed obvious gastric ulcers, gastrointestinal perforation, and intestinal hemorrhage in the gastrointestinal tract, but no lesions in other organs. The microbial species in gastric samples collected from gastric ulcer of the diseased sows then was initially identified as Candida by using routine systems of microscopic examination, culture characteristics on the medium Sabouraud dextrose agar medium. The fungus was further identified as C. tropicalis by species-specific PCR and sequencing. This study revealed an infection of C. tropicalis in sows through gastrointestinal mucosa could cause fatal digestive system disease and septicemia. CONCLUSIONS: For the first time, a strain of C. tropicalis was isolated and identified from the gastric tissue of sows with severe gastrointestinal diseases. PCR and sequencing of ITS-rDNA combined with morphology and histopathological assay were reliable for the identification of Candida clinically.


Asunto(s)
Candida tropicalis/aislamiento & purificación , Candidiasis/veterinaria , Enfermedades Gastrointestinales/veterinaria , Enfermedades de los Porcinos/microbiología , Alimentación Animal/efectos adversos , Animales , Candida tropicalis/clasificación , Candida tropicalis/genética , Candidiasis/mortalidad , Candidiasis/patología , China/epidemiología , ADN Ribosómico , Femenino , Enfermedades Gastrointestinales/microbiología , Enfermedades Gastrointestinales/mortalidad , Enfermedades Gastrointestinales/patología , Reacción en Cadena de la Polimerasa/veterinaria , Porcinos , Enfermedades de los Porcinos/mortalidad
13.
J Appl Microbiol ; 131(2): 728-742, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33103297

RESUMEN

AIM: Tyrosol, a quorum sensing molecule in yeasts, was reported to reduce lag phase and induces hyphae formation during cell proliferation. However, evidence of any enhancing effect of tyrosol in cellular proliferation within fermentative environment is unclear. In this investigation, selected yeast cells were assessed for their ability to synthesize tyrosol followed by examining the role of the molecule during fermentation. METHODS AND RESULTS: Tyrosols were characterized in four fermentative yeasts viz., Saccharomyces cerevisiae, Wickerhamomyces anomalus, Candida glabrata and Candida tropicalis isolated from traditional fermentative cakes of northeast India. All the isolates synthesized tyrosol while C. tropicalis exhibited filamentous growth in response to tyrosols retrieved from other isolates. Purified tyrosols showed protective behaviour in C. tropicalis and S. cerevisiae under ethanol mediated oxidative stress. During fermentation, tyrosol significantly enhanced growth of W. anomalus in starch medium while C. tropicalis exhibited growth enhancement in starch and glucose sources. The chief fermentative yeast S. cerevisiae showed notable enhancement in fermentative capacity in starch medium under the influence of tyrosol con-commitment of ethanol production. CONCLUSION: The study concludes that tyrosol exerts unusual effect in cellular growth and fermentative ability of both Saccharomyces and non-Saccharomyces yeasts. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report of expression of tyrosol by non-conventional yeasts, where the molecule was found to exert enhancing effect during fermentation, thereby augmenting the process of metabolite production during traditional fermentation.


Asunto(s)
Fermentación , Alcohol Feniletílico/análogos & derivados , Percepción de Quorum , Levaduras/metabolismo , Candida/aislamiento & purificación , Candida/metabolismo , Candida glabrata/aislamiento & purificación , Candida glabrata/metabolismo , Candida tropicalis/efectos de los fármacos , Candida tropicalis/crecimiento & desarrollo , Candida tropicalis/aislamiento & purificación , Candida tropicalis/metabolismo , Etanol/metabolismo , Etanol/toxicidad , India , Alcohol Feniletílico/metabolismo , Saccharomyces/aislamiento & purificación , Saccharomyces/metabolismo , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/aislamiento & purificación , Saccharomyces cerevisiae/metabolismo , Saccharomycetales/crecimiento & desarrollo , Saccharomycetales/aislamiento & purificación , Saccharomycetales/metabolismo
14.
J Med Microbiol ; 70(2)2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33252326

RESUMEN

Introduction. Candida species can form biofilms on tissues and medical devices, making them less susceptible to antifungal agents.Hypothesis/Gap Statement. Antifungal combination may be an effective strategy to fight against Candida biofilm.Aim. In this study, we investigated the in vitro activity of fluconazole, caspofungin and amphotericin B, alone and in combination, against 17 clinical Candida tropicalis and 6 Candida parapsilosis isolates with high biofilm formation. We also tested LL-37 and lysozyme for anti-biofilm activity against a selected C. tropicalis isolate.Methodology. Candida biofilms were prepared using the 96-well plate-based method. The minimum biofilm eradication concentrations were determined for single and combined antifungal drugs. The activity of LL-37 and lysozyme was determined by visual reading for planktonic cells and using the XTT assay for biofilms.Results. Under biofilm conditions, fluconazole plus caspofungin showed synergistic effects against 60.9% (14 of 23) of the tested isolates, including 70.6% of C. tropicalis [fractional inhibitory concentration index (FICI), 0.26-1.03] and 33.3% of C. parapsilosis (FICI, 0.04-2.03) isolates. Using this combination, no antagonism was observed. Amphotericin B plus caspofungin showed no effects against 78.3% (18 of 23) of the tested isolates. Amphotericin B plus fluconazole showed no effects against 65.2% (15 of 23) of the tested isolates and may have led to antagonism against 2 C. tropicalis and 2 C. parapsilosis isolates. LL-37 and lysozyme had no effect on biofilms of the selected C. tropicalis isolate.Conclusions. We found that fluconazole plus caspofungin led to a synergistic effect against C. tropicalis and C. parapsilosis biofilms. The efficacy of the antifungal combination therapies of the proposed schemes against biofilm-associated Candida infections requires careful and constant evaluation.


Asunto(s)
Antifúngicos/farmacología , Biopelículas/efectos de los fármacos , Candida parapsilosis/efectos de los fármacos , Candida tropicalis/efectos de los fármacos , Catelicidinas/farmacología , Muramidasa/farmacología , Anfotericina B/farmacología , Péptidos Catiónicos Antimicrobianos , Biopelículas/crecimiento & desarrollo , Candida parapsilosis/aislamiento & purificación , Candida tropicalis/aislamiento & purificación , Caspofungina/farmacología , Combinación de Medicamentos , Fluconazol/farmacología , Humanos
15.
J Mycol Med ; 30(4): 101043, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32948435

RESUMEN

Candida tropicalis is an emerging fungal pathogen associated with high mortality. We aimed to compare adherence capability of C. tropicalis to polystyrene and epithelial cell lines (HeLa and Vero), and determine whether adherent blastoconidia is cell-type specific. Blastoconidia adhesion to epithelial cells and polystyrene were determined by crystal violet assay. The percentage of epithelial cells with adhered blastoconidia and the number of adhered blastoconidia per cell line were determined by light microscopy. The correlation between adhesion surfaces was assessed by Pearson's correlation coefficient. The adhesiveness of C. tropicalis to polystyrene was greater than that observed for ephitelial cells. High correlation values (r2 0.9999222, p 0.007941) were found for the adhesion capability between biotic and polystyrene surface for isolates 100.10 (obtained from blood) and 335.07 (obtained from tracheal secretion). The number of adherent blastoconidia per HeLa cell was greater in comparison to that observed for Vero cells (P<0.05). Further, high correlation (r2 1, p 0.0001) was found for the adhesion ability between HeLa cells and Vero cells. The results suggest a correlation of C. tropicalis adhesion capability among different surfaces, and that the adhesion to epithelial cells is specific to the cell type.


Asunto(s)
Candida tropicalis/fisiología , Adhesión Celular/fisiología , Células Epiteliales/microbiología , Poliestirenos , Animales , Candida tropicalis/aislamiento & purificación , Candida tropicalis/patogenicidad , Candida tropicalis/ultraestructura , Chlorocebus aethiops , Células Epiteliales/ultraestructura , Células HeLa , Humanos , Microscopía Confocal , Poliestirenos/química , Propiedades de Superficie , Células Vero
16.
Microbiologyopen ; 9(11): e1121, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32985133

RESUMEN

Candida tropicalis is a common human pathogenic yeast, and its molecular typing is important for studying the population structure and epidemiology of this opportunistic yeast, such as epidemic genotype, population dynamics, nosocomial infection, and drug resistance surveillance. In this study, the antifungal susceptibility test and multilocus sequence typing (MLST) analysis were carried out on C. tropicalis from central China. Among 64 urogenital isolates, 45 diploid sequence types (DST) were found, of which 20 DSTs (44.4%) were new to the central database. The goeBURST analysis showed that CC1 (clonal complex) was the only azole-resistant (100%, 10/10) cluster in Wuhan, which was composed of DST546, DST225, DST376, and DST506, and most of the strains (90%, 9/10) were isolated from the urinary tract. Potential nosocomial infections were mainly caused by CC1 strains. The azole resistance rate of urinary isolates (50.0%, 21/42) was higher than that of vaginal isolates (27.3%, 6/22). The genotype diversity and novelty of vaginal isolates were higher than those of urinary isolates. C. tropicalis population in Wuhan was genetically diverse and divergent from that seen in other countries. In this study, there were significant differences in genotype and azole susceptibility between urine and vaginal strains. The azole-resistant cluster (CC1) found in urine is of great significance for the clinical treatment and prevention of nosocomial infection. The newly discovered DSTs will contribute to further study the similarity, genetic relationship, and molecular epidemiology of C. tropicalis worldwide.


Asunto(s)
Azoles/uso terapéutico , Candida tropicalis/aislamiento & purificación , Candidiasis/epidemiología , Farmacorresistencia Fúngica/genética , Infecciones del Sistema Genital/epidemiología , Infecciones Urinarias/epidemiología , Antifúngicos/uso terapéutico , Candida tropicalis/efectos de los fármacos , Candida tropicalis/genética , Candidiasis/tratamiento farmacológico , Candidiasis/microbiología , China/epidemiología , Infección Hospitalaria/microbiología , Femenino , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Epidemiología Molecular , Tipificación de Secuencias Multilocus , Técnicas de Tipificación Micológica , Infecciones del Sistema Genital/tratamiento farmacológico , Infecciones del Sistema Genital/microbiología , Infecciones Urinarias/tratamiento farmacológico , Infecciones Urinarias/microbiología
17.
Ecotoxicol Environ Saf ; 206: 111203, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-32866888

RESUMEN

Degradation of the prothioconazole by three strains of microorganisms isolated from activated sludge obtained from a pesticide factory was assessed, and an ultrahigh-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QqTOF-MS) method for the determination of prothioconazole and its metabolites was established. The optimal conditions for the degradation of prothioconazole were determined by single factor optimization experiments. A degradation rate of 93.32% is achieved when the prothioconazole is co-cultured with the strain W313 at a cultivation time of 60 h, a cultivation temperature of 30 °C, a pH of 6.33, a prothioconazole concentration of 50 mg L-1, a microorganism volume of 10%, and a dextrose volume of 4%. The three effective microorganism strains were identified by morphological and molecular biology to be Candida tropicalis, Enterobacter cloacae, and Pseudomonas aeruginosa. UPLC-QqTOF-MS analysis allowed the identification of 62 different prothioconazole degradation products produced by the strain cultures, with prothioconazole-desthio, prothioconazole-dechloropropyl, and oxidizing prothioconazole being the main products. In addition, degradation products from different strains and conditions were compared. The results of scatter plot (S-Plot) analysis indicated that C9H7NO, C10H17N7, and C12H13ClN2O were only detected in the products incubated with Enterobacter cloacae. Thus, this study demonstrates that Enterobacter cloacae and Pseudomonas aeruginosa possesses high potential for bioremediation of prothioconazole-contaminated environments.


Asunto(s)
Plaguicidas/análisis , Pseudomonas aeruginosa/metabolismo , Aguas del Alcantarillado/microbiología , Triazoles/análisis , Biodegradación Ambiental , Candida tropicalis/aislamiento & purificación , Candida tropicalis/metabolismo , Cromatografía Líquida de Alta Presión , Enterobacter cloacae/aislamiento & purificación , Enterobacter cloacae/metabolismo , Espectrometría de Masas , Modelos Teóricos , Plaguicidas/metabolismo , Pseudomonas aeruginosa/aislamiento & purificación , Aguas del Alcantarillado/química , Triazoles/metabolismo
18.
Rev Peru Med Exp Salud Publica ; 37(2): 276-281, 2020.
Artículo en Español, Inglés | MEDLINE | ID: mdl-32876217

RESUMEN

Retrospective descriptive study carried out to determine the characteristics of fungemia in 285 cancer patients hospitalized from 2012 to 2016 at the Instituto Nacional de Enfermedades Neoplásicas (INEN). Demographic, clinical and microbiological information was evaluated. Fungemia by C. albicans predominated in patients with solid tumors and without neutropenia, while those caused by C. tropicalis predominated in patients with hematological neoplasia and neutropenia. C. tropicalis was the agent isolated in most cases (47.0%). Fungemia increased over time in patients without neutropenia. Fungemia caused by C. albicans increases with age in patients with solid tumors without neutropenia. It is concluded that fungemia are mainly caused by C. tropicalis in patients with hematological neoplasia with neutropenia and by C. albicans in patients with solid tumors without neutropenia. In addition, fungemia in patients without neutropenia increases over time; and those caused by C. albicans increase with age in patients with solid tumors without neutropenia.


Con el objetivo de conocer las características de las fungemias en 285 pacientes oncológicos hospitalizados del 2012 al 2016 en el Instituto Nacional de Enfermedades Neoplásicas se realizó un estudio descriptivo retrospectivo. Se evaluó información demográfica, clínica y microbiológica. Las fungemias por C. albicans predominaron en pacientes con tumores sólidos y sin neutropenia, mientras las causadas por C. tropicalis predominaron en pacientes con neoplasias hematológicas y neutropenia. C. tropicalis fue el agente más aislado (47,0%). Las fungemias aumentaron con el tiempo en los pacientes sin neutropenia. Las fungemias causadas por C. albicans aumentan con la edad en pacientes con tumores sólidos sin neutropenia. Se concluye que las fungemias son mayormente causadas por C. tropicalis en pacientes con neoplasias hematológicas con neutropenia y por C. albicans en pacientes con tumores sólidos sin neutropenia. Además, las fungemias en pacientes sin neutropenia aumentan en el tiempo y las causadas por C. albicans, en tumores sólidos sin neutropenia, aumentan con la edad.


Asunto(s)
Candidiasis , Fungemia , Candida albicans/aislamiento & purificación , Candida tropicalis/aislamiento & purificación , Candidiasis/complicaciones , Candidiasis/epidemiología , Candidiasis/microbiología , Fungemia/complicaciones , Fungemia/epidemiología , Fungemia/microbiología , Humanos , Neoplasias/complicaciones , Neoplasias/terapia , Perú/epidemiología , Derivación y Consulta , Estudios Retrospectivos
19.
PLoS One ; 15(8): e0237263, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32764812

RESUMEN

BACKGROUND: Chronic infected wounds are generally difficult to manage and treatment can be particularly challenging in resource-limited settings where diagnostic testing is not readily available. In this study, the epidemiology of microbial pathogens in chronically infected wounds in rural Ghana was assessed to support therapeutic choices for physicians. METHODS: Culture-based bacterial diagnostics including antimicrobial resistance testing were performed on samples collected from patients with chronic wounds at a hospital in Asante Akim North Municipality, Ghana. Fungal detection was performed by broad-range fungal PCR and sequencing of amplicons. RESULTS: In total, 105 patients were enrolled in the study, from which 207 potential bacterial pathogens were isolated. Enterobacteriaceae (n = 84, 41%) constituted the most frequently isolated group of pathogens. On species level, Pseudomonas aeruginosa (n = 50, 24%) and Staphylococcus aureus (n = 28, 14%) were predominant. High resistance rates were documented, comprising 29% methicillin resistance in S. aureus as well as resistance to 3rd generation cephalosporins and fluoroquinolones in 33% and 58% of Enterobacteriaceae, respectively. One P. aeruginosa strain with carbapenem resistance was identified. The most frequently detected fungi were Candida tropicalis. CONCLUSIONS: The pathogen distribution in chronic wounds in rural Ghana matched the internationally observed patterns with a predominance of P. aeruginosa and S. aureus. Very high resistance rates discourage antibiotic therapy but suggest an urgent need for microbiological diagnostic approaches, including antimicrobial resistance testing to guide the management of patients with chronic wounds in Ghana.


Asunto(s)
Antibacterianos/farmacología , Bacterias/aislamiento & purificación , Hongos/aislamiento & purificación , Infección de Heridas/tratamiento farmacológico , Infección de Heridas/microbiología , Adulto , Anciano , Animales , Antibacterianos/uso terapéutico , Bacterias/efectos de los fármacos , Candida tropicalis/efectos de los fármacos , Candida tropicalis/aislamiento & purificación , Farmacorresistencia Bacteriana , Farmacorresistencia Fúngica , Femenino , Hongos/efectos de los fármacos , Ghana/epidemiología , Hospitales de Distrito , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/aislamiento & purificación , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/aislamiento & purificación , Infección de Heridas/epidemiología , Adulto Joven
20.
Future Microbiol ; 15: 1001-1013, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32811174

RESUMEN

Aim: To compare the pathogenesis of vulvovaginal candidiasis by three Candida species in diabetic mice. Materials & methods: Estrogenized and diabetic mice were challenged with C. albicans, C. tropicalis and C. glabrata. Results: Diabetic animals infected with C. albicans and C. tropicalis maintained the highest fungal burden, despite of high levels of proinflammatory cytokines (IL-6 and TNF-α), respectively. For C. glabrata, the results were similar in diabetic and nondiabetic groups. Conclusion:C. tropicalis was as invasive as C. albicans, and both were more effective than C. glabrata. This ability was attributed to filamentation, which may be stimulated by glucose levels from vaginal fluid. In addition, the high burden may be attributed to the apparent immunological inefficiency of the diabetic host.


Asunto(s)
Candida albicans/fisiología , Candida glabrata/fisiología , Candida tropicalis/fisiología , Candidiasis Vulvovaginal/microbiología , Complicaciones de la Diabetes/microbiología , Animales , Candida albicans/genética , Candida albicans/aislamiento & purificación , Candida glabrata/genética , Candida glabrata/aislamiento & purificación , Candida tropicalis/genética , Candida tropicalis/aislamiento & purificación , Candidiasis Vulvovaginal/etiología , Candidiasis Vulvovaginal/genética , Candidiasis Vulvovaginal/metabolismo , Complicaciones de la Diabetes/etiología , Complicaciones de la Diabetes/genética , Complicaciones de la Diabetes/metabolismo , Modelos Animales de Enfermedad , Femenino , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Ratones , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo
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