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1.
J Mycol Med ; 34(1): 101453, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38042016

RESUMO

We report a severe case of kerion Celsi of the scalp in a previously healthy 13-year-old girl due to Trichophyton quinckeanum, an emerging dermatophyte species in Europe. The species was definitely identified by DNA sequencing and the patient was successfully treated by oral terbinafine for 6 weeks. Kerion Celsi is a severe inflammatory form of tinea capitis, which is characterised by a purulent discharge and alopecia [1]. It typically occurs in children infected with zoophilic dermatophytes, such as Trichophyton mentagrophytes, and an increasing number of cases caused by other Trichophyton species has recently been reported [2]. Herein we report a severe case of kerion Celsi of the scalp caused by the emerging species Trichophyton quinckeanum, which was successfully treated by oral antifungal.


Assuntos
Arthrodermataceae , Tinha do Couro Cabeludo , Criança , Feminino , Humanos , Adolescente , Tinha do Couro Cabeludo/diagnóstico , Tinha do Couro Cabeludo/tratamento farmacológico , Tinha do Couro Cabeludo/microbiologia , Trichophyton/genética , Antifúngicos/uso terapêutico
2.
Antimicrob Agents Chemother ; 67(4): e0146222, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-36892306

RESUMO

The clinical involvement and antifungal susceptibility of Aspergillus section Circumdati are poorly known. We analyzed 52 isolates, including 48 clinical isolates, belonging to 9 species inside the section Circumdati. The whole section exhibited, by the EUCAST reference method, a poor susceptibility to amphotericin B, but species/series-specific patterns were observed for azole drugs. This underlines the interest in getting an accurate identification inside the section Circumdati to guide the choice of antifungal treatment in clinical practice.


Assuntos
Antifúngicos , Aspergillus , Antifúngicos/farmacologia , Testes de Sensibilidade Microbiana , Anfotericina B/farmacologia , Azóis/farmacologia
3.
Med Mycol ; 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33111143

RESUMO

New mold species are increasingly reported in invasive fungal infections. However, these fungi are often misdiagnosed or undiagnosed due to the use of inappropriate laboratory diagnostic tools. Tropical countries, such as French Guiana, harbor a vast diversity of environmental fungi representing a potential source of emerging pathogens. To assess the impact of this diversity on the accuracy of mold-infection diagnoses, we identified mold clinical isolates in French Guiana during a five-month follow-up using both microscopy and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. In total, 38.8% of the 98 obtained molds isolates could not be identified and required a DNA-based identification. Fungal diversity was high, including 46 species, 26 genera, and 13 orders. Fungal ecology was unusual, as Aspergillus species accounted for only 27% of all isolates, and the Nigri section was the most abundant out of the six detected Aspergillus sections. Macromycetes (orders Agaricales, Polyporales, and Russulales) and endophytic fungi accounted for respectively 11% and 14% of all isolates. Thus, in tropical areas with high fungal diversity, such as French Guiana, routine mold identification tools are inadequate. Molecular identifications, as well as morphological descriptions, are necessary for the construction of region-specific mass spectrum databases. These advances will improve the diagnosis and clinical management of new fungal infections. LAY SUMMARY: In French Guiana, environmental fungal diversity may be a source of emerging pathogens. We evaluated microscopy and mass spectrometry to identify mold clinical isolates. With 39% of unidentified isolates, a region-specific mass spectrum database would improve the diagnosis of new fungal infections.

4.
Antimicrob Agents Chemother ; 64(12)2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-32900686

RESUMO

The antifungal susceptibility of Aspergillus cryptic species is poorly known. We assessed 51 isolates, belonging to seven Fumigati cryptic species, by the EUCAST reference method and the concentration gradient strip (CGS) method. Species-specific patterns were observed, with high MICs for azole drugs, except for Aspergillus hiratsukae and Aspergillus tsurutae, and high MICs for amphotericin B for Aspergillus lentulus and Aspergillus udagawae Essential and categorical agreements between EUCAST and CGS results were between 53.3 and 93.3%.


Assuntos
Antifúngicos , Aspergillus , Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Testes de Sensibilidade Microbiana
5.
Artigo em Inglês | MEDLINE | ID: mdl-32312779

RESUMO

Aspergillus niger, the third species responsible for invasive aspergillosis, has been considered as a homogeneous species until DNA-based identification uncovered many cryptic species. These species have been recently reclassified into the Aspergillus section Nigri However, little is yet known among the section Nigri about the species distribution and the antifungal susceptibility pattern of each cryptic species. A total of 112 clinical isolates collected from 5 teaching hospitals in France and phenotypically identified as A. niger were analyzed. Identification to the species level was carried out by nucleotide sequence analysis. The MICs of itraconazole, voriconazole, posaconazole, isavuconazole, and amphotericin B were determined by both the EUCAST and gradient concentration strip methods. Aspergillus tubingensis (n = 51, 45.5%) and Aspergillus welwitschiae (n = 50, 44.6%) were the most common species while A. niger accounted for only 6.3% (n = 7). The MICs of azole drugs were higher for A. tubingensis than for A. welwitschiae The MIC of amphotericin B was 2 mg/liter or less for all isolates. Importantly, MICs determined by EUCAST showed no correlation with those determined by the gradient concentration strip method, with the latter being lower than the former (Spearman's rank correlation tests ranging from 0.01 to 0.25 depending on the antifungal agent; P > 0.4). In conclusion, A. niger should be considered as a minority species in the section Nigri The differences in MICs between species for different azoles underline the importance of accurate identification. Significant divergences in the determination of MIC between EUCAST and the gradient concentration strip methods require further investigation.


Assuntos
Antifúngicos , Itraconazol , Antifúngicos/farmacologia , Aspergillus , França , Testes de Sensibilidade Microbiana
6.
Fungal Syst Evol ; 4: 171-181, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32467910

RESUMO

We describe the isolation and characterization of Fusarium volatile from a bronchoalveolar lavage (BAL) sample of a female patient living in French Guiana with underlying pulmonary infections. Phylogenetic analysis of fragments of the calmodulin (cmdA), translation elongation factor (tef1), RNA polymerase second largest subunit (rpb2), and ß-tubulin (tub) loci revealed that strain CBS 143874 was closely related to isolate NRRL 25615, a known but undescribed phylogenetic species belonging to the African clade of the Fusarium fujikuroi species complex. The fungus differed phylogenetically and morphologically from related known species, and is therefore described as the new taxon Fusarium volatile. Antifungal susceptibility testing suggested that the new species is resistant to echinocandins, fluconazole, itraconazole with lower MICs against amphotericin B, voriconazole and posaconazole.

7.
Clin Microbiol Infect ; 25(7): 892-897, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30394360

RESUMO

OBJECTIVES: The purpose of this study was to compare the efficiency of mould identification of two matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) systems - Vitek MS (VMS) and Microflex LT (MLT) - and the MSI application. METHODS: Moulds were collected retrospectively and prospectively to display epidemiological diversity of a microbiology laboratory. All of them were identified via sequencing. Strains were then identified using the VMS v3.0, the MLT, and the MSI software applied on MLT spectra. Rates of correct identifications to the species, to the complex, and to the genus level were compared with the molecular reference standard. RESULTS: A total of 102 isolates were collected. The rate of correct identification to the species level with the MLT was 42.2% (43/102) with a threshold of 1.7 (vs. 16.7% (17/102) with a threshold of 2.0, p < 0.05). The VMS performed better than the MLT with a threshold of 1.7 for species (49.0% (50/102), p 0.33) and complex level identifications (71.6% (73/102) vs. 54.9% (56/102), p < 0.05). However the highest performances were observed when the MLT spectra were analysed via the Mass Spectrometry Identification (MSI) software reaching 90.2% (92/102) of correct identification to the species, 92.2% (94/102) to the species complex and 94.1% (96/102) to the genus level. CONCLUSIONS: The VMS performed better than the MLT for mould identification. However, it remains of utmost importance to expand commercial databases, as performances of the MLT highly improved when using the MSI software and its extended database, reaching far above the VMS system. Thus the VMS could benefit from the use of this online tool.


Assuntos
Fungos/isolamento & purificação , Micoses/diagnóstico , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Bases de Dados Factuais , Fungos/genética , Humanos , Micoses/microbiologia , Reação em Cadeia da Polimerase , Estudos Prospectivos , Estudos Retrospectivos , Análise de Sequência de DNA , Software
8.
J Clin Microbiol ; 56(5)2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29491019

RESUMO

Conventional dermatophyte identification is based on morphological features. However, recent studies have proposed to use the nucleotide sequences of the rRNA internal transcribed spacer (ITS) region as an identification barcode of all fungi, including dermatophytes. Several nucleotide databases are available to compare sequences and thus identify isolates; however, these databases often contain mislabeled sequences that impair sequence-based identification. We evaluated five of these databases on a clinical isolate panel. We selected 292 clinical dermatophyte strains that were prospectively subjected to an ITS2 nucleotide sequence analysis. Sequences were analyzed against the databases, and the results were compared to clusters obtained via DNA alignment of sequence segments. The DNA tree served as the identification standard throughout the study. According to the ITS2 sequence identification, the majority of strains (255/292) belonged to the genus Trichophyton, mainly T. rubrum complex (n = 184), T. interdigitale (n = 40), T. tonsurans (n = 26), and T. benhamiae (n = 5). Other genera included Microsporum (e.g., M. canis [n = 21], M. audouinii [n = 10], Nannizzia gypsea [n = 3], and Epidermophyton [n = 3]). Species-level identification of T. rubrum complex isolates was an issue. Overall, ITS DNA sequencing is a reliable tool to identify dermatophyte species given that a comprehensive and correctly labeled database is consulted. Since many inaccurate identification results exist in the DNA databases used for this study, reference databases must be verified frequently and amended in line with the current revisions of fungal taxonomy. Before describing a new species or adding a new DNA reference to the available databases, its position in the phylogenetic tree must be verified.


Assuntos
Arthrodermataceae/classificação , Arthrodermataceae/genética , Código de Barras de DNA Taxonômico/métodos , Dermatomicoses/microbiologia , Arthrodermataceae/isolamento & purificação , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Dermatomicoses/diagnóstico , Humanos , Filogenia , Estudos Prospectivos , Análise de Sequência de DNA
9.
J Mycol Med ; 28(2): 320-326, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29580647

RESUMO

The objective of our study was to assess the DiversiLab® automated repetitive sequence-based PCR (rep-PCR) system for typing C. albicans and C. glabrata isolates and to compare it with two proven and routinely used typing methods. A total of 39 isolates from 11 patients with candidaemia or tissue candidiasis (two to six isolates per patient) were analyzed with three typing methods: DiversiLab® rep-PCR, multilocus sequence typing and multilocus microsatellite typing. DiversiLab® rep-PCR results were consistent with those obtained using the two other typing methods for C. albicans, but not for C. glabrata. Thanks to its simplicity of use, rapidity, standardization and reproducibility, the DiversiLab® rep-PCR system is an interesting tool to investigate C. albicans infections.


Assuntos
Candida albicans/classificação , Candida glabrata/classificação , Reação em Cadeia da Polimerase/métodos , Sequências Repetitivas de Ácido Nucleico , Automação , Candida albicans/isolamento & purificação , Candida glabrata/isolamento & purificação , Candidíase/diagnóstico , Candidíase/microbiologia , Genótipo , Humanos , Repetições de Microssatélites , Tipagem de Sequências Multilocus , Técnicas de Tipagem Micológica , Reação em Cadeia da Polimerase/normas , Reprodutibilidade dos Testes
10.
Artigo em Inglês | MEDLINE | ID: mdl-29439956

RESUMO

Aspergillus section Terrei is a species complex currently comprised of 14 cryptic species whose prevalence in clinical samples as well as antifungal susceptibility are poorly known. The aims of this study were to investigate A. Terrei clinical isolates at the species level and to perform antifungal susceptibility analyses by reference and commercial methods. Eighty-two clinical A. Terrei isolates were collected from 8 French university hospitals. Molecular identification was performed by sequencing parts of beta-tubulin and calmodulin genes. MICs or minimum effective concentrations (MECs) were determined for 8 antifungal drugs using both EUCAST broth microdilution (BMD) methods and concentration gradient strips (CGS). Among the 79 A. Terrei isolates, A. terreus stricto sensu (n = 61), A. citrinoterreus (n = 13), A. hortai (n = 3), and A. alabamensis (n = 2) were identified. All strains had MICs of ≥1 mg/liter for amphotericin B, except for two isolates (both A. hortai) that had MICs of 0.25 mg/liter. Four A. terreus isolates were resistant to at least one azole drug, including one with pan-azole resistance, yet no mutation in the CYP51A gene was found. All strains had low MECs for the three echinocandins. The essential agreements (EAs) between BMD and CGS were >90%, except for those of amphotericin B (79.7%) and itraconazole (73.4%). Isolates belonging to the A section Terrei identified in clinical samples show wider species diversity beyond the known A. terreus sensu stricto Azole resistance inside the section Terrei is uncommon and is not related to CYP51A mutations here. Finally, CGS is an interesting alternative for routine antifungal susceptibility testing.


Assuntos
Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Aspergillus/genética , Anfotericina B/farmacologia , Azóis/farmacologia , Equinocandinas/farmacologia , Humanos , Itraconazol/farmacologia , Testes de Sensibilidade Microbiana
11.
J Clin Microbiol ; 55(9): 2661-2670, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28637907

RESUMO

Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry has emerged as a reliable technique to identify molds involved in human diseases, including dermatophytes, provided that exhaustive reference databases are available. This study assessed an online identification application based on original algorithms and an extensive in-house reference database comprising 11,851 spectra (938 fungal species and 246 fungal genera). Validation criteria were established using an initial panel of 422 molds, including dermatophytes, previously identified via DNA sequencing (126 species). The application was further assessed using a separate panel of 501 cultured clinical isolates (88 mold taxa including dermatophytes) derived from five hospital laboratories. A total of 438 (87.35%) isolates were correctly identified at the species level, while 26 (5.22%) were assigned to the correct genus but the wrong species and 37 (7.43%) were not identified, since the defined threshold of 20 was not reached. The use of the Bruker Daltonics database included in the MALDI Biotyper software resulted in a much higher rate of unidentified isolates (39.76 and 74.30% using the score thresholds 1.7 and 2.0, respectively). Moreover, the identification delay of the online application remained compatible with real-time online queries (0.15 s per spectrum), and the application was faster than identifications using the MALDI Biotyper software. This is the first study to assess an online identification system based on MALDI-TOF spectrum analysis. We have successfully applied this approach to identify molds, including dermatophytes, for which diversity is insufficiently represented in commercial databases. This free-access application is available to medical mycologists to improve fungal identification.


Assuntos
Arthrodermataceae/classificação , Bases de Dados Factuais , Dermatomicoses/diagnóstico , Técnicas de Tipagem Micológica/métodos , Sistemas On-Line , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Algoritmos , Dermatomicoses/microbiologia , Humanos , Técnicas de Tipagem Micológica/instrumentação , Software
12.
Clin Microbiol Infect ; 22(8): 662-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27263029

RESUMO

The use of multi-locus DNA sequence analysis has led to the description of previously unknown 'cryptic' Aspergillus species, whereas classical morphology-based identification of Aspergillus remains limited to the section or species-complex level. The current literature highlights two main features concerning these 'cryptic' Aspergillus species. First, the prevalence of such species in clinical samples is relatively high compared with emergent filamentous fungal taxa such as Mucorales, Scedosporium or Fusarium. Second, it is clearly important to identify these species in the clinical laboratory because of the high frequency of antifungal drug-resistant isolates of such Aspergillus species. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) has recently been shown to enable the identification of filamentous fungi with an accuracy similar to that of DNA sequence-based methods. As MALDI-TOF MS is well suited to the routine clinical laboratory workflow, it facilitates the identification of these 'cryptic' Aspergillus species at the routine mycology bench. The rapid establishment of enhanced filamentous fungi identification facilities will lead to a better understanding of the epidemiology and clinical importance of these emerging Aspergillus species. Based on routine MALDI-TOF MS-based identification results, we provide original insights into the key interpretation issues of a positive Aspergillus culture from a clinical sample. Which ubiquitous species that are frequently isolated from air samples are rarely involved in human invasive disease? Can both the species and the type of biological sample indicate Aspergillus carriage, colonization or infection in a patient? Highly accurate routine filamentous fungi identification is central to enhance the understanding of these previously unknown Aspergillus species, with a vital impact on further improved patient care.


Assuntos
Aspergilose/microbiologia , Aspergillus/classificação , Animais , Antifúngicos/farmacologia , Aspergilose/epidemiologia , Aspergillus/efeitos dos fármacos , Aspergillus/genética , Aspergillus/isolamento & purificação , Farmacorresistência Fúngica , Genes Fúngicos , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Vigilância da População , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
14.
Med Mycol ; 53(5): 462-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25841053

RESUMO

Utilizing matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectra for Candida glabrata typing would be a cost-effective and easy-to-use alternative to classical DNA-based typing methods. This study aimed to use MALDI-TOF for the typing of C. glabrata clinical isolates from various geographical origins and test its capacity to differentiate between fluconazole-sensitive and -resistant strains.Both microsatellite length polymorphism (MLP) and MALDI-TOF mass spectra of 58 C. glabrata isolates originating from Marseilles (France) and Tunis (Tunisia) as well as collection strains from diverse geographic origins were analyzed. The same analysis was conducted on a subset of C. glabrata isolates that were either susceptible (MIC ≤ 8 mg/l) or resistant (MIC ≥ 64 mg/l) to fluconazole.According to the seminal results, both MALDI-TOF and MLP classifications could highlight C. glabrata population structures associated with either geographical dispersal barriers (p < 10(-5)) or the selection of antifungal drug resistance traits (<10(-5)).In conclusion, MALDI-TOF geographical clustering was congruent with MPL genotyping and highlighted a significant population genetic structure according to fluconazole susceptibility in C. glabrata. Furthermore, although MALDI-TOF and MLP resulted in distinct classifications, MALDI-TOF also classified the isolates with respect to their fluconazole susceptibility profile. Further prospective studies are required to evaluate the capacity of MALDI-TOF typing to investigate C. glabrata infection outbreaks and predict the antifungal susceptibility profile of clinical laboratory isolates.


Assuntos
Antifúngicos/farmacologia , Candida glabrata/isolamento & purificação , Candidíase/epidemiologia , Farmacorresistência Fúngica , Fluconazol/farmacologia , Técnicas de Tipagem Micológica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Candida glabrata/química , Candida glabrata/classificação , Candida glabrata/efeitos dos fármacos , Candidíase/microbiologia , Análise por Conglomerados , França/epidemiologia , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Repetições de Microssatélites , Tipagem Molecular , Fenótipo , Topografia Médica , Tunísia/epidemiologia
15.
J Mass Spectrom ; 50(2): 371-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25800019

RESUMO

Candida albicans is the most frequent yeast involved in human infections. Its population structure can be divided into several genetic clades, some of which have been associated with antifungal susceptibility. Therefore, detecting and monitoring fungal clones in a routine laboratory setting would be a major epidemiological advance. Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectra results are now widely used as bar codes to identify microorganisms in clinical microbiology laboratories. This study aimed at testing MALDI-TOF mass spectra bar codes to identify clades among a set of C. albicans isolates. Accordingly, 102 clinical strains were genotyped using 10 microsatellite markers and analyzed via MALDI-TOF mass spectrometry. The mass spectra were compared with a reference spectral library including 33 well-characterized collection strains, using a Microflex(TM) system and Biotyper(TM) software, to test the capacity of the spectrum of a given isolate to match with the reference mass spectrum of an isolate from the same genetic clade. Despite high confidence species identification, the spectra failed to significantly match with the corresponding clade (p = 0.74). This was confirmed with the MALDI-TOF spectra similarity dendrogram, in which the strains were dispersed irrespective of their genetic clade. Various attempts to improve intra-clade spectra recognition were unsuccessful. In conclusion, MALDI-TOF mass spectra bar code analysis failed to reliably recognize genetically related C. albicans isolates. Further studies are warranted to develop alternative MALDI-TOF mass spectra analytical approaches to identify and monitor C. albicans clades in the routine clinical laboratory.


Assuntos
Candida albicans/genética , DNA Fúngico/análise , Repetições de Microssatélites/genética , Tipagem Molecular/métodos , Micologia/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Candida albicans/classificação , Candidíase/microbiologia , DNA Fúngico/química , DNA Fúngico/genética , Humanos
16.
Pathol Biol (Paris) ; 62(6): 369-76, 2014 Dec.
Artigo em Francês | MEDLINE | ID: mdl-25212790

RESUMO

AIM: The aim of this work is to know the fertility rate of the metacestodes resulting from patients suffering from hydatidosis, the one of protoscoleces's viability and by comparing the results obtained with those found elsewhere. It reports, also, the epidemiological, clinical and diagnostically aspects of the studied patients. MATERIALS AND METHODS: This study has carried on 78 hydatics samples resulting from 78 patients collected between 2005 and 2012 at the laboratory of parasitology of the Mustapha hospital center of Algiers. A questionnaire on the epidemiological context (contact with an animal-host of the cycle, place of residence, presence of family cases reached of hydatidosis and knowledge on the hydatic disease) concerned 69 patients. For each sample, a direct microscopic examination is made with or without vital staining. The presence of protoscoleces made qualified the fertile cyst. Those visualized moving or resistant to eosin at 0.2% are considered viables. Indirect diagnosis is based on the techniques: passive hemagglutination, electrophoresis, Elisa IgG Echinococcus granulosus and immunoblotting IgG "Echinococcus". Molecular analysis is based on PCR and sequencing the partials fragments of two mitochondrial genes with the primers COX1 and ND1. RESULTS: The results obtained show that the surgical frequency of hydatidosis is significant at the young adult and at the child. The epidemiological context associated at the disease is the conjointly presence of a dog and herbivores. The fertility rate of human hydatid cysts is 88.4% and the ones of viability of the protoscoleces is 74.5%. In this series, the serology shows global positivity at 70%. The molecular characterization of five samples identify the species: E. granulosus ss. CONCLUSION: Finally, the viability and fertility rates found here are raised. Sometimes viables protoscoleses are found after use of scolicidal solution. In front of these results, the parasitical treatment is more than necessary in order to minimize the risk of occurred of secondary echinococcosis or the relapses postoperatives.


Assuntos
Equinococose/epidemiologia , Equinococose/parasitologia , Adolescente , Adulto , Idoso , Argélia/epidemiologia , Animais , Animais Domésticos , Criança , Pré-Escolar , Estudos de Coortes , Cães , Feminino , Hospitais Universitários , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
17.
Clin Microbiol Infect ; 20(12): 1366-71, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24995483

RESUMO

The clinical diagnosis of mould infections currently involves complex species identification based on morphological criteria, which is often prone to error. Employing an extensive mould species reference spectral library (up to 2832 reference spectra, corresponding to 708 strains from 347 species), we assessed the extent to which matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) enhanced the accuracy of species identification. MALDI-TOF MS data were validated against morphology-based and DNA sequence-based results with 262 clinical isolates collected over a 4-month period in 2013. The implementation of MALDI-TOF MS resulted in a dramatic improvement in mould identification at the species level (from 78.2% to 98.1%) and a marked reduction in the misidentification rate (from 9.8% to 1.2%). We then compared the mould identification results obtained before (i.e. 2011) and after (i.e. 2013) the implementation of MALDI-TOF MS in routine identification procedures, which showed an improvement from 64.57% to 100%. Reassessment of a set of isolates from 2011 with this procedure, including MALDI-TOF MS, yielded an increase in species diversity from 16 to 42 species. Finally, application of this procedure during a 16-month period (2012-2013) enabled the identification of 1094 of 1107 (98.8%) clinical mould isolates corresponding to 107 distinct species. MALDI-TOF MS-based mould species identification may soon challenge traditional techniques in the clinical laboratory, as patient prognosis is largely contingent on rapid and accurate diagnosis.


Assuntos
Técnicas de Laboratório Clínico/métodos , Fungos/isolamento & purificação , Técnicas Microbiológicas/métodos , Micoses/diagnóstico , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Humanos , Sensibilidade e Especificidade
18.
Clin Microbiol Infect ; 20(6): 551-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24165542

RESUMO

Matrix-assisted laser desorption ionization time-of-flightMALDI-TOF mass spectrometry (MS) is now widely recognized as a powerful tool with which to identify bacteria and fungi at the species level, and sometimes in a rapid and accurate manner. We report herein an approach to identify, at the species level, Leishmania promastigotes from in vitro culture. We first constructed a reference database of spectra including the main Leishmania species known to cause human leishmaniasis. Then, the performance of the reference database in identifying Leishmania promastigotes was tested on a panel of 69 isolates obtained from patients. Our approach correctly identified 66 of the 69 isolates tested at the species level with log (score) values superior to 2. Two Leishmania isolates yielded non-interpretable MALDI-TOF MS patterns, owing to low log (score) values. Only one Leishmania isolate of Leishmania peruviana was misidentified as the closely related species Leishmania braziliensis, with a log (score) of 2.399. MALDI-TOF MS is a promising approach, providing rapid and accurate identification of Leishmania from in vitro culture at the species level.


Assuntos
Técnicas de Laboratório Clínico/métodos , Leishmania/química , Leishmania/classificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Humanos , Parasitologia/métodos , Fatores de Tempo
19.
Braz. j. med. biol. res ; 42(11): 1035-1038, Nov. 2009. tab
Artigo em Inglês | LILACS | ID: lil-529098

RESUMO

Anesthetics can affect the structure and biological function of tissues and systems differentially. The aim of the present study was to compare three injectable anesthetics generally used in experiments with animals in terms of the degree of hemolysis and glycogenolysis occurring after profound anesthesia. Twenty-four male Wistar rats (330-440 g) were divided into three groups (N = 8): chloral hydrate (CH), ketamine + xylazine (KX), Zoletil 50® (zolazepam and tiletamine) + xylazine (ZTX). After deep anesthesia, total blood was collected. The liver and white (WG) and red gastrocnemius (RG) muscles were also immediately removed. The degree of serum hemolysis was quantified on the basis of hemoglobin concentration (g/L). Hepatic and muscular glycogen concentrations (mmol/kg wet tissue) were quantified by the phenol-sulfuric method. The CH and KX groups exhibited serum hemolysis (4.0 ± 2.2 and 1.9 ± 0.9 g/L, respectively; P < 0.05) compared to the ZTX group, which presented none. Only KX induced elevated glycogenolysis (mmol/kg wet tissue) in the liver (86.9 ± 63.2) and in WG (18.7 ± 9.0) and RG (15.2 ± 7.2; P < 0.05). The CH and ZTX groups exhibited no glycogenolysis in the liver (164.4 ± 41.1 and 176.8 ± 54.4, respectively), WG (28.8 ± 4.4, 32.0 ± 6.5, respectively) or RG (29.0 ± 4.9; 25.3 ± 8.6, respectively). Our data indicate that ZTX seems to be an appropriate general anesthetic for studies that seek to simultaneously quantify the concentration of glycogen and serum biochemical markers without interferences. ZTX is reasonably priced, found easily at veterinary markets, quickly induces deep anesthesia, and presents a low mortality rate.


Assuntos
Animais , Masculino , Ratos , Anestésicos Gerais/farmacologia , Glicogenólise/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Glicogênio Hepático/metabolismo , Músculos/efeitos dos fármacos , Biomarcadores/análise , Combinação de Medicamentos , Ketamina/farmacologia , Músculos/enzimologia , Ratos Wistar , Tiletamina/farmacologia , Xilazina/farmacologia , Zolazepam/farmacologia
20.
Braz J Med Biol Res ; 42(11): 1035-8, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19802466

RESUMO

Anesthetics can affect the structure and biological function of tissues and systems differentially. The aim of the present study was to compare three injectable anesthetics generally used in experiments with animals in terms of the degree of hemolysis and glycogenolysis occurring after profound anesthesia. Twenty-four male Wistar rats (330-440 g) were divided into three groups (N = 8): chloral hydrate (CH), ketamine + xylazine (KX), Zoletil 50(R) (zolazepam and tiletamine) + xylazine (ZTX). After deep anesthesia, total blood was collected. The liver and white (WG) and red gastrocnemius (RG) muscles were also immediately removed. The degree of serum hemolysis was quantified on the basis of hemoglobin concentration (g/L). Hepatic and muscular glycogen concentrations (mmol/kg wet tissue) were quantified by the phenol-sulfuric method. The CH and KX groups exhibited serum hemolysis (4.0 +/- 2.2 and 1.9 +/- 0.9 g/L, respectively; P < 0.05) compared to the ZTX group, which presented none. Only KX induced elevated glycogenolysis (mmol/kg wet tissue) in the liver (86.9 +/- 63.2) and in WG (18.7 +/- 9.0) and RG (15.2 +/- 7.2; P < 0.05). The CH and ZTX groups exhibited no glycogenolysis in the liver (164.4 +/- 41.1 and 176.8 +/- 54.4, respectively), WG (28.8 +/- 4.4, 32.0 +/- 6.5, respectively) or RG (29.0 +/- 4.9; 25.3 +/- 8.6, respectively). Our data indicate that ZTX seems to be an appropriate general anesthetic for studies that seek to simultaneously quantify the concentration of glycogen and serum biochemical markers without interferences. ZTX is reasonably priced, found easily at veterinary markets, quickly induces deep anesthesia, and presents a low mortality rate.


Assuntos
Anestésicos Gerais/farmacologia , Glicogenólise/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Glicogênio Hepático/metabolismo , Músculos/efeitos dos fármacos , Animais , Biomarcadores/análise , Combinação de Medicamentos , Ketamina/farmacologia , Masculino , Músculos/enzimologia , Ratos , Ratos Wistar , Tiletamina/farmacologia , Xilazina/farmacologia , Zolazepam/farmacologia
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