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1.
Eur J Neurol ; 31(1): e16030, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37548584

RESUMO

BACKGROUND: Acute hepatitis E virus (HEV) infection has recently emerged as a potential trigger for acute dysimmune neuropathies, but prospective controlled studies are lacking. AIMS: To compare the frequency of concomitant acute HEV infection in patients with neuralgic amyotrophy (NA), Guillain-Barré syndrome (GBS), and Bell's palsy with a matched control population. METHODS: Swiss multicenter, prospective, observational, matched case-control study over 3 years (September 2019-October 2022). Neurological cases with NA, GBS, or Bell's palsy were recruited within 1 month of disease onset. Healthy controls were matched for age, sex, geographical location, and timing of blood collection. Diagnostic criteria for acute hepatitis E were reactive serum anti-HEV IgM and IgG assays (ELISA test) and/or HEV RNA detection in serum by real-time polymerase chain reaction (RT-PCR). RT-PCR was performed on sera to confirm IgM positivity. RESULTS: We included 180 patients (59 GBS, 51 NA, 70 Bell's palsy cases) and corresponding matched controls (blood donors) with median age 51 years for both groups and equal gender distribution. Six IgM+ cases were detected in the NA, two in the GBS, and none in the Bell's palsy group. Two controls were anti-HEV IgM-positive. At disease onset, most cases with acute HEV infection had increased liver enzymes. A moderate association (p = 0.027, Fisher's exact test; Cramér's V = -0.25) was observed only between acute HEV infection and NA. CONCLUSION: This prospective observational study suggests an association between concomitant acute HEV infection and NA, but not with GBS or Bell's palsy.


Assuntos
Paralisia de Bell , Paralisia Facial , Síndrome de Guillain-Barré , Vírus da Hepatite E , Hepatite E , Humanos , Pessoa de Meia-Idade , Vírus da Hepatite E/genética , Hepatite E/complicações , Hepatite E/epidemiologia , Hepatite E/diagnóstico , Estudos de Casos e Controles , Estudos Prospectivos , Paralisia de Bell/complicações , Síndrome de Guillain-Barré/epidemiologia , Anticorpos Anti-Hepatite , Doença Aguda , Imunoglobulina M
2.
Microorganisms ; 11(10)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37894033

RESUMO

From 2014 to 2016, the number of hepatitis E virus (HEV) infections in southern Switzerland increased dramatically and suggested food as a potential infection reservoir. We evaluated the effects of food control measures introduced to limit HEV infections, assessing anti-HEV IgG and IgM rates in blood donors before and after the implementation of food control measures in 2017. From 2012 to 2013, we screened 1283, and from 2017 to 2019, we screened 1447 donors for IgG and IgM antibodies. No statistically significant differences were detected for IgG (32.8% from 2012 to 2013 vs. 31.1% from 2017 to 2019, p = 0.337) or IgM rates (2.0% from 2012 to 2013 vs. 2.8% from 2017 to 2019, p = 0.21). Rural provenience and age > 66 are predictors for positive IgG serology. A total of 5.9% of 303 donors included in both groups lost IgG positivity. We also determined nucleic acid testing (NAT) rates after the introduction of this test in 2018, comparing 49,345 donation results from southern Switzerland with those of 625,559 Swiss donor controls, and only 9 NAT-positive donors were found from 2018 to 2023. The high HEV seroprevalence in southern Switzerland may depend on different food supply chains in rural and urban areas. Local preventive measures probably have a limited impact on blood HEV risk; thus, continuous NAT testing is recommended.

3.
Bot Stud ; 64(1): 6, 2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36905471

RESUMO

BACKGROUND: The biodiversity of the mycobiota of soft cheese rinds such as Brie or Camembert has been extensively studied, but scant information is available on the fungi colonizing the rinds of cheese produced in the Southern Switzerland Alps. This study aimed at exploring the fungal communities present on rinds of cheese matured in five cellars in Southern Switzerland and to evaluate their composition with regards to temperature, relative humidity, type of cheese, as well as microenvironmental and geographic factors. We used macro- and microscopical morphology, matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry, and sequencing to characterize the fungal communities of the cheeses, and compared them with metabarcoding targeting the ITS region. RESULTS: Isolation by serial dilution yielded 201 isolates (39 yeasts and 162 filamentous fungi) belonging to 9 fungal species. Mucor and Penicillium were dominant, with Mucor racemosus, M. lanceolatus, P. biforme, and P. chrysogenum/rubens being the most frequent species. All but two yeast isolates were identified as Debaryomyces hansenii. Metabarcoding detected 80 fungal species. Culture work and metabarcoding produced comparable results in terms of similarity of the fungal cheese rind communities in the five cellars. CONCLUSIONS: Our study has shown that the mycobiota on the rinds of the cheeses studied is a comparatively species-poor community influenced by temperature, relative humidity, type of cheese, and manufacturing steps, as well as microenvironmental and possibly geographic factors.

4.
Pathogens ; 10(2)2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33498993

RESUMO

After an acute hepatitis E (HEV) outbreak in Southern Switzerland, in January 2017 the local public health authorities started an active program of food chain control and public education. In this retrospective study, we analysed all laboratory-confirmed acute cases of HEV infection diagnosed between 2014 and 2020. In the period before the public health intervention, the number of cases increased steadily from 2014 (4 of 40 tests, 10%) reaching a peak in the last quarter of 2016 (42 of 285 tests, 14.7 %). Afterwards, the number of positive cases decreased steadily, reaching its lowest value (0.3%) in the second quarter of 2019. There was a statistically significant difference between the frequency of positive cases and period of testing, i.e., before and after the introduction of the public health interventions. Our study shows that active public health measures to control sausages containing raw pork liver can reduce the prevalence of HEV infection.

5.
Mycologia ; 111(1): 177-189, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30640580

RESUMO

Protein fingerprinting using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI--TOF MS) is a rapid, reliable, and economical method to characterize isolates of terrestrial fungi and other microorganisms. The objective of our study was to evaluate the suitability of MALDI-TOF MS for the identification of aquatic hyphomycetes, a polyphyletic group of fungi that play crucial roles in stream ecosystems. To this end, we used 34 isolates of 21 aquatic hyphomycete species whose identity was confirmed by spore morphology and internal transcribed spacer (ITS1-5.8S-ITS2 = ITS) nuc rDNA sequencing. We tested the efficiency of three protein extraction methods, including chemical and mechanical treatments using 13 different protocols, with the objective of producing high-quality MALDI-TOF mass spectra. In addition to extraction protocols, mycelium age was identified as a key parameter affecting protein extraction efficiency. The dendrogram based on mass-spectrum similarity indicated good and relevant taxonomic discrimination; the tree structure was comparable to that of the phylogram based on ITS sequences. Consequently, MALDI-TOF MS could reliably identify the isolates studied and provided greater taxonomic accuracy than classical morphological methods. MALDI-TOF MS seems suited for rapid characterization and identification of aquatic hyphomycete species.


Assuntos
Proteínas Fúngicas/análise , Fungos Mitospóricos/classificação , Filogenia , Microbiologia da Água , Análise por Conglomerados , França , Fungos Mitospóricos/química , Proteômica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
6.
Clin Med Insights Ear Nose Throat ; 12: 1179550618821930, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30670922

RESUMO

BACKGROUND: Upper and lower respiratory tract infections are common conditions for which medical advice is sought, and their management relies on the use of prescription and over-the-counter (OTC) medicines. Ambroxol, bromhexine, carbocysteine, erdosteine, N-acetyl cysteine (NAC), and sobrerol are mucoactive agents for which clinical trials have been conducted, have been awarded well-established status by regulatory authorities, and are available as OTC or prescription products. OBJECTIVE: To briefly review the evidence-based efficacy and safety of these substances in the therapy of upper respiratory airways infections. METHODS: We conducted searches in MEDLINE and other databases for clinical trials and reviews done on the efficacy and safety of ambroxol, bromhexine, carbocysteine, erdosteine, NAC, and sobrerol. RESULTS: Clinical trials have shown that these mucolytics have an important place in the relief of cough symptoms by easing the elimination of mucus. All drugs have shown comparable efficacy in the symptomatic treatment of productive cough, with some shared characteristics and some specific features. CONCLUSIONS AND RELEVANCE: All mucolytics reviewed have a good safety profile, although some precautions should be taken when using ambroxol and bromhexine, and the use of NAC and carbocysteine should be monitored in special patient groups. Overall, however, the available evidence from randomised, controlled, and observational trials, as well as pragmatic, real-life experience, suggests that these products are useful in the therapy of upper respiratory airways infections, including bronchitis, sinusitis, and rhinosinusitis.

7.
PLoS One ; 12(9): e0182962, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28877205

RESUMO

The fast and reliable characterization of bacterial and fungal pathogens plays an important role in infectious disease control and tracking of outbreak agents. DNA based methods are the gold standard for epidemiological investigations, but they are still comparatively expensive and time-consuming. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a fast, reliable and cost-effective technique now routinely used to identify clinically relevant human pathogens. It has been used for subspecies differentiation and typing, but its use for epidemiological tasks, e. g. for outbreak investigations, is often hampered by the complexity of data analysis. We have analysed publicly available MALDI-TOF mass spectra from a large outbreak of Shiga-Toxigenic Escherichia coli in northern Germany using a general purpose software tool for the analysis of complex biological data. The software was challenged with depauperate spectra and reduced learning group sizes to mimic poor spectrum quality and scarcity of reference spectra at the onset of an outbreak. With high quality formic acid extraction spectra, the software's built in classifier accurately identified outbreak related strains using as few as 10 reference spectra (99.8% sensitivity, 98.0% specificity). Selective variation of processing parameters showed impaired marker peak detection and reduced classification accuracy in samples with high background noise or artificially reduced peak counts. However, the software consistently identified mass signals suitable for a highly reliable marker peak based classification approach (100% sensitivity, 99.5% specificity) even from low quality direct deposition spectra. The study demonstrates that general purpose data analysis tools can effectively be used for the analysis of bacterial mass spectra.


Assuntos
Surtos de Doenças , Infecções por Escherichia coli/microbiologia , Escherichia coli Shiga Toxigênica/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Estatística como Assunto , Biomarcadores/análise
8.
J Clin Microbiol ; 52(12): 4286-92, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25297329

RESUMO

The objective of this research was to extend the Vitek MS fungal knowledge base version 2.0.0 to allow the robust identification of clinically relevant dermatophytes, using a variety of strains, incubation times, and growth conditions. First, we established a quick and reliable method for sample preparation to obtain a reliable and reproducible identification independently of the growth conditions. The Vitek MS V2.0.0 fungal knowledge base was then expanded using 134 well-characterized strains belonging to 17 species in the genera Epidermophyton, Microsporum, and Trichophyton. Cluster analysis based on mass spectrum similarity indicated good species discrimination independently of the culture conditions. We achieved a good separation of the subpopulations of the Trichophyton anamorph of Arthroderma benhamiae and of anthropophilic and zoophilic strains of Trichophyton interdigitale. Overall, the 1,130 mass spectra obtained for dermatophytes gave an estimated identification performance of 98.4%. The expanded fungal knowledge base was then validated using 131 clinical isolates of dermatophytes belonging to 13 taxa. For 8 taxa all strains were correctly identified, and for 3 the rate of successful identification was >90%; 75% (6/8) of the M. gypseum strains were correctly identified, whereas only 47% (18/38) of the African T. rubrum population (also called T. soudanense) were recognized accurately, with a large quantity of strains misidentified as T. violaceum, demonstrating the close relationship of these two taxa. The method of sample preparation was fast and efficient and the expanded Vitek MS fungal knowledge base reliable and robust, allowing reproducible dermatophyte identifications in the routine laboratory.


Assuntos
Arthrodermataceae/química , Arthrodermataceae/classificação , Técnicas Microbiológicas/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Arthrodermataceae/isolamento & purificação , Análise por Conglomerados , Dermatomicoses/diagnóstico , Humanos , Micologia/métodos , Fatores de Tempo
9.
BMC Microbiol ; 14: 105, 2014 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-24767577

RESUMO

BACKGROUND: Flavobacterium psychrophilum is the agent of Bacterial Cold Water Disease and Rainbow Trout Fry Syndrome, two diseases leading to high mortality. Pathogen detection is mainly carried out using cultures and more rapid and sensitive methods are needed. RESULTS: We describe a qPCR technique based on the single copy gene ß' DNA-dependent RNA polymerase (rpoC). Its detection limit was 20 gene copies and the quantification limit 103 gene copies per reaction. Tests on spiked spleens with known concentrations of F. psychrophilum (106 to 101 cells per reaction) showed no cross-reactions between the spleen tissue and the primers and probe. Screening of water samples and spleens from symptomless and infected fishes indicated that the pathogen was already present before the outbreaks, but F. psychrophilum was only quantifiable in spleens from diseased fishes. CONCLUSIONS: This qPCR can be used as a highly sensitive and specific method to detect F. psychrophilum in different sample types without the need for culturing. qPCR allows a reliable detection and quantification of F. psychrophilum in samples with low pathogen densities. Quantitative data on F. psychrophilum abundance could be useful to investigate risk factors linked to infections and also as early warning system prior to potential devastating outbreak.


Assuntos
Técnicas Bacteriológicas/métodos , Doenças dos Peixes/microbiologia , Infecções por Flavobacteriaceae/veterinária , Flavobacterium/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Microbiologia da Água , Animais , Infecções por Flavobacteriaceae/microbiologia , Flavobacterium/genética , Oncorhynchus mykiss , Sensibilidade e Especificidade
10.
Dis Aquat Organ ; 105(3): 203-10, 2013 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-23999704

RESUMO

Bacterial cold water disease (BCWD) and rainbow trout fry syndrome (RTFS) caused by Flavobacterium psychrophilum are 2 of the major diseases causing high fish mortality in salmonid fish farms. The molecular epidemiology of F. psychrophilum is still largely unknown. Multilocus sequence typing (MLST) has been previously used for this pathogen and underscored a correlation between clonal complexes and host fish species. Here we used MLST to study the relationships among 112 F. psychrophilum isolates from rainbow trout Oncorhynchus mykiss and brown trout Salmo trutta fario and S. t. lacustris in Swiss fish farms between 1993 and 2012. The isolates belonged to 27 different sequence types (STs). Most of the Swiss outbreaks were associated with strains belonging to clonal complexes CC-ST2 and CC-ST90, found in both rainbow trout and brown trout and represented by several STs. Eight ST singletons could not be connected to any known clonal complex. Already reported from other parts of Europe and North America, CC-ST2 was the most frequent clonal complex observed, and it caused the majority of outbreaks in Switzerland, with CC-ST90 being the second most important type. In the tightly interconnected Swiss fish farms, no association between clonal complex and host fish was detected, but a temporal evolution of the frequency of some STs was observed. The occurrence of sporadic STs suggests high F. psychrophilum diversity and may reflect the presence of different sequence types in the environment.


Assuntos
Doenças dos Peixes/microbiologia , Infecções por Flavobacteriaceae/veterinária , Flavobacterium/genética , Epidemiologia Molecular , Truta , Animais , Surtos de Doenças/veterinária , Infecções por Flavobacteriaceae/epidemiologia , Infecções por Flavobacteriaceae/microbiologia , Flavobacterium/classificação , Variação Genética , Filogenia , Suíça/epidemiologia
11.
J Vet Sci ; 14(4): 449-56, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23820161

RESUMO

We investigated the distribution of commensal staphylococcal species and determined the prevalence of multi-drug resistance in healthy cats and dogs. Risk factors associated with the carriage of multi-drug resistant strains were explored. Isolates from 256 dogs and 277 cats were identified at the species level using matrix-assisted laser desorption ionisation-time of flight mass spectrometry. The diversity of coagulase-negative Staphylococci (CNS) was high, with 22 species in dogs and 24 in cats. Multi-drug resistance was frequent (17%) and not always associated with the presence of the mecA gene. A stay in a veterinary clinic in the last year was associated with an increased risk of colonisation by multi-drug resistant Staphylococci (OR = 2.4, 95% CI: 1.1~5.2, p value LRT = 0.04). When identifying efficient control strategies against antibiotic resistance, the presence of mechanisms other than methicillin resistance and the possible role of CNS in the spread of resistance determinants should be considered.


Assuntos
Antibacterianos/farmacologia , Doenças do Gato/microbiologia , Doenças do Cão/microbiologia , Farmacorresistência Bacteriana Múltipla , Infecções Estafilocócicas/veterinária , Staphylococcus/isolamento & purificação , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Doenças do Gato/epidemiologia , Gatos , Coagulase/genética , Coagulase/metabolismo , Doenças do Cão/epidemiologia , Cães , Feminino , Masculino , Prevalência , Fatores de Risco , Estações do Ano , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/veterinária , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus/classificação , Staphylococcus/genética , Suíça/epidemiologia
12.
Am J Infect Control ; 41(9): 831-5, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23422230

RESUMO

BACKGROUND: Animals could be reservoirs of extended-spectrum ß-lactamases (ESBL) strains, but epidemiologic data on ESBL-producing bacteria in healthy pets are missing. We determined the prevalence of ESBL-producing Enterobacteriaceae in pets living in nursing homes and in households to investigate the potential role of companion animals as carriers of ESBL. METHODS: Three hundred seventy-six rectal swabs were taken from cats and dogs visiting or living in 68 randomly selected nursing homes or brought to 26 veterinary practices in Switzerland for routine mandatory vaccination. Isolates were identified by matrix-assisted laser desorption ionization time of flight mass spectrometry. Confirmatory tests were performed on the isolated Enterobacteriaceae. Phenotypic ESBL isolates were investigated for genetic determinants of resistance. RESULTS: The overall prevalence of ESBL isolates, adjusted for clustering, was 2.5% (95% confidence interval: 1.3-4.6). Pets that received an antibiotic treatment in the 3 months prior to the study had a higher risk to be carriers of these microorganisms (Adjusted odds ratio, 7.8; 95% confidence interval: 2.2-26.9). CONCLUSION: ESBL-producing Enterobacteriaceae were present in healthy cats and dogs, particularly from those with a history of antibiotic treatment. These animals could become ESBL reservoirs. Investigations are needed to assess the possible transmission of these microorganisms between pets and humans.


Assuntos
Portador Sadio/veterinária , Infecções por Enterobacteriaceae/veterinária , Enterobacteriaceae/enzimologia , Enterobacteriaceae/isolamento & purificação , Animais de Estimação/microbiologia , beta-Lactamases/metabolismo , Animais , Técnicas Bacteriológicas , Portador Sadio/epidemiologia , Portador Sadio/microbiologia , Gatos , Estudos Transversais , Cães , Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/microbiologia , Características da Família , Feminino , Masculino , Casas de Saúde , Prevalência , Reto/microbiologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Suíça/epidemiologia , beta-Lactamases/genética
13.
Med Mycol ; 51(5): 514-21, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23228046

RESUMO

In this study we evaluated the suitability of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for the identification of dermatophytes in diagnostic laboratories. First, a spectral database was built with 108 reference strains belonging to 18 species of the anamorphic genera Epidermophyton, Microsporum and Trichophyton. All strains were well characterized by morphological criteria and ITS sequencing (gold standard). The dendrogram resulting from MALDI-TOF mass spectra was almost identical with the phylogenetic tree based on ITS sequencing. Subsequently, MALDI-TOF MS SuperSpectra were created for the identification of Epidermophyton floccosum, Microsporium audouinii, M. canis, M. gypseum (teleomorph: Arthroderma gypseum), M. gypseum (teleomorph: A. incurvatum), M. persicolor, A. benhamiae (Tax. Entity 3 and Am-Eur. race), T. erinacei, T. interdigitale (anthropophilic and zoophilic populations), T. rubrum/T. violaceum, T. tonsurans and T. terrestre. Because T. rubrum and T. violaceum did not present enough mismatches, a SuperSpectrum covering both species was created, and differentiation between them was done by comparison of eight specific peptide masses. In the second part of this study, MALDI-TOF MS with the newly created SuperSpectra was tested using 141 clinical isolates representing nine species. Analyses were done with 3-day-old cultures. Results were compared to morphological identification and ITS sequencing; 135/141 (95.8%) strains were correctly identified by MALDI-TOF MS compared to 128/141 (90.8%) by morphology. Therefore, MALDI-TOF MS has proven to be a useful and rapid identification method for dermatophytes.


Assuntos
Arthrodermataceae/química , Arthrodermataceae/classificação , Técnicas de Laboratório Clínico/métodos , Micologia/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Humanos , Dados de Sequência Molecular , Filogenia , Sensibilidade e Especificidade , Análise de Sequência de DNA , Fatores de Tempo
14.
PLoS One ; 7(11): e49280, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23152887

RESUMO

F. psychrophilum is the causative agent of Bacterial Cold Water Disease (BCW) and Rainbow Trout Fry Syndrome (RTFS). To date, diagnosis relies mainly on direct microscopy or cultural methods. Direct microscopy is fast but not very reliable, whereas cultural methods are reliable but time-consuming and labor-intensive. So far fluorescent in situ hybridization (FISH) has not been used in the diagnosis of flavobacteriosis but it has the potential to rapidly and specifically detect F. psychrophilum in infected tissues. Outbreaks in fish farms, caused by pathogenic strains of Flavobacterium species, are increasingly frequent and there is a need for reliable and cost-effective techniques to rapidly diagnose flavobacterioses. This study is aimed at developing a FISH that could be used for the diagnosis of F. psychrophilum infections in fish. We constructed a generic probe for the genus Flavobacterium ("Pan-Flavo") and two specific probes targeting F. psychrophilum based on 16S rRNA gene sequences. We tested their specificity and sensitivity on pure cultures of different Flavobacterium and other aquatic bacterial species. After assessing their sensitivity and specificity, we established their limit of detection and tested the probes on infected fresh tissues (spleen and skin) and on paraffin-embedded tissues. The results showed high sensitivity and specificity of the probes (100% and 91% for the Pan-Flavo probe and 100% and 97% for the F. psychrophilum probe, respectively). FISH was able to detect F. psychrophilum in infected fish tissues, thus the findings from this study indicate this technique is suitable as a fast and reliable method for the detection of Flavobacterium spp. and F. psychrophilum.


Assuntos
Flavobacterium/genética , Flavobacterium/isolamento & purificação , Hibridização in Situ Fluorescente/métodos , Animais , Sondas de DNA/metabolismo , DNA Ribossômico/genética , Doenças dos Peixes/diagnóstico , Doenças dos Peixes/microbiologia , Peixes/microbiologia , Infecções por Flavobacteriaceae/diagnóstico , Infecções por Flavobacteriaceae/microbiologia , Infecções por Flavobacteriaceae/veterinária , Limite de Detecção , Inclusão em Parafina , Curva ROC , Análise de Sequência de DNA
15.
PLoS One ; 7(10): e48441, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23119019

RESUMO

The genus Aeromonas has undergone a number of taxonomic and nomenclature revisions over the past 20 years, and new (sub)species and biogroups are continuously described. Standard identification methods such as biochemical characterization have deficiencies and do not allow clarification of the taxonomic position. This report describes the development of a matrix-assisted laser desorption/ionisation-time of flight mass spectrometry (MALDI-TOF MS) identification database for a rapid identification of clinical and environmental Aeromonas isolates.


Assuntos
Aeromonas/genética , Bases de Dados Genéticas , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Aeromonas/classificação , Análise por Conglomerados , Humanos , Filogenia
16.
Mycologia ; 104(5): 1036-45, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22492405

RESUMO

Guignardia bidwellii is the etiological agent of grape black rot, a disease affecting Vitis and other Vitaceae that can cause heavy crop losses in vineyards. Its identification is based mainly on morphological characters and the symptoms on plants but, due to their variability, they may be difficult to interpret to reliably distinguish the pathogen to species. To date, despite the economic importance of G. bidwellii, no molecular investigations have been carried out on Vitis isolates and few sequence data are available for cultures derived from ornamental host plants. We analyzed samples of G. bidwellii collected from grapevine cultivars and ornamental plants of various geographic origins by morphological, molecular and proteomic techniques, including ITS1-ITS2 regions and calmodulin gene sequencing, as well as matrix-assisted laser desorption/ionization analysis by time-of-flight mass spectrometry (MALDI-TOF MS). This polyphasic approach allowed assessing the phylogenetic relationships among the different isolates and suggested the existence of two distinct species. The advantages of a polyphasic approach for the identification of G. bidwellii are highlighted.


Assuntos
Ascomicetos/classificação , Micoses/microbiologia , Vitis/microbiologia , Ascomicetos/citologia , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Sequência de Bases , DNA Fúngico/genética , Dados de Sequência Molecular , Filogenia , Proteômica/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
17.
Am J Infect Control ; 40(2): 128-33, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21824684

RESUMO

BACKGROUND: Pets, often used as companionship and for psychological support in the therapy of nursing home residents, have been implicated as reservoirs for antibiotic-resistant bacteria. We investigated the importance of pets as reservoirs of multidrug-resistant (MDR) staphylococci in nursing homes. METHODS: We assessed the carriage of MDR staphylococci in pets and in 2 groups of residents, those living in nursing homes with pets and those living without pet contacts. We collected demographic, health status, and human-pet contact data by means of questionnaires. We assessed potential bacteria transmission pathways by investigating physical resident-to-pet contact. RESULTS: The observed prevalence of MDR staphylococci carriage was 84/229 (37%) in residents living with pets and 99/216 (46%) in those not living with pets (adjusted odds ratio [aOR], 0.6; 95% confidence interval [CI], 0.4-0.9). Active pet contact was associated with lower carriage of MDR staphylococci (aOR, 0.5; 95% CI, 0.4-0.8). Antibiotic treatment during the previous 3 months was associated with significantly increased risk for MDR carriage in residents (aOR, 3.1; 95% CI, 1.8-5.7). CONCLUSIONS: We found no evidence that the previously reported benefits of pet contact are compromised by the increased risk of carriage of MDR staphylococci in residents associated with interaction with these animals in nursing homes. Thus, contact with pets, always under good hygiene standards, should be encouraged in these settings.


Assuntos
Portador Sadio/veterinária , Reservatórios de Doenças/veterinária , Animais de Estimação/microbiologia , Infecções Estafilocócicas/veterinária , Idoso , Idoso de 80 Anos ou mais , Animais , Portador Sadio/microbiologia , Portador Sadio/transmissão , Gatos , Reservatórios de Doenças/microbiologia , Cães , Farmacorresistência Bacteriana Múltipla , Feminino , Humanos , Masculino , Casas de Saúde , Razão de Chances , Prevalência , Fatores de Risco , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/transmissão , Staphylococcus/fisiologia , Inquéritos e Questionários , Suíça/epidemiologia
18.
Syst Appl Microbiol ; 34(1): 45-51, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21300509

RESUMO

The Staphylococcus intermedius Group includes S. intermedius, S. pseudintermedius and S. delphini, coagulase-positive bacteria commonly isolated from animals. The identification of organisms belonging to this group is presently carried out using molecular methods. This study assessed the suitability of MALDI-TOF MS for their identification. 69 strains of different biological and geographic origins, identified by partial hsp60 gene sequencing as S. intermedius (n=15), S. pseudintermedius (n=32) and S. delphini (n=22), were analyzed by MALDI-TOF MS. The estimated sensitivity, specificity and efficiency were calculated. In addition we computed the agreement between the outcome of MALDI-TOF MS identification and partial hsp60 gene sequencing. The sensitivity of MALDI-TOF MS was higher for S. intermedius [0.95 (95% CI: 0.68-0.99)], than for S. pseudintermedius [0.78 (95% CI: 0.60-0.90)] and S. delphini [0.64 (95% CI: 0.41-0.83)], whereas the specificity was 1 for S. intermedius and S. delphini and 0.97 (95% CI: 0.86-0.99) for S. pseudintermedius. The Cohen's kappa coefficient indicated almost perfect agreement between MALDI-TOF MS and hsp60 gene sequencing for the identification of S. intermedius [0.96 (95% CI: 0.87-1.04)], and substantial agreement for S. delphini and S. pseudintermedius [0.70 (95% CI: 0.52-0.89) and 0.76 (95% CI: 0.616-0.92), respectively]. The overall efficiency of the proteomic identification ranged between 0.88 (95% CI: 0.78-0.95) for S. pseudintermedius and S. delphini and 0.99 (95% CI: 0.92-0.99) for S. intermedius. MALDI-TOF MS is thus a valuable and reliable tool for the rapid and accurate identification of bacteria belonging to the S. intermedius Group.


Assuntos
Técnicas Bacteriológicas/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Staphylococcus/química , Staphylococcus/classificação , Proteínas de Bactérias/genética , Chaperonina 60/genética , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , Dados de Sequência Molecular , Filogenia , Sensibilidade e Especificidade , Análise de Sequência de DNA
19.
PLoS One ; 6(1): e16424, 2011 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-21283545

RESUMO

BACKGROUND: Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) allows rapid and reliable identification of microorganisms, particularly clinically important pathogens. METHODOLOGY/PRINCIPAL FINDINGS: We compared the identification efficiency of MALDI-TOF MS with that of Phoenix®, API® and 16S ribosomal DNA sequence analysis on 1,019 strains obtained from routine diagnostics. Further, we determined the agreement of MALDI-TOF MS identifications as compared to 16S gene sequencing for additional 545 strains belonging to species of Enterococcus, Gardnerella, Staphylococcus, and Streptococcus. For 94.7% of the isolates MALDI-TOF MS results were identical with those obtained with conventional systems. 16S sequencing confirmed MALDI-TOF MS identification in 63% of the discordant results. Agreement of identification of Gardnerella, Enterococcus, Streptococcus and Staphylococcus species between MALDI-TOF MS and traditional method was high (Crohn's kappa values: 0.9 to 0.93). CONCLUSIONS/SIGNIFICANCE: MALDI-TOF MS represents a rapid, reliable and cost-effective identification technique for clinically relevant bacteria.


Assuntos
Bactérias/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Enterococcus/isolamento & purificação , Gardnerella/isolamento & purificação , RNA Ribossômico 16S , Análise de Sequência , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/normas , Staphylococcus/isolamento & purificação , Streptococcus/isolamento & purificação
20.
Mycologia ; 102(4): 944-66, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20648760

RESUMO

Analysis of a worldwide collection of strains of Trichoderma asperellum sensu lato using multilocus genealogies of four genomic regions (tef1, rpb2, act, ITS1, 2 and 5.8s rRNA), sequence polymorphism-derived (SPD) markers, matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) of the proteome and classical mycological techniques revealed two morphologically cryptic sister species within T. asperellum, T. asperellum, T. asperelloides sp. nov. and a third closely related but morphologically distinct species. T. yunnanense. Trichoderma asperellum and T. asperelloides have wide sympatric distribution on multiple continents; T. yunnanense is represented by a single strain from China. Several strains reported in the literature or represented in GenBank as T. asperellum are re-identified as T. asperelloides. Four molecular SPD typing patterns (I-IV) were found over a large geographic range. Patterns I-III were produced only by T. asperellum and pattern IV by T. asperelloides and T. yunnanense. Pattern I was found in North America, South America, Africa and Europe and Asia (Saudi Arabia). Pattern III was found in Africa, North America, South America and Asia, not in Europe. Pattern II was found only in Cameroon (central Africa) and Peru. Pattern IV was found in all continents. All SPD II pattern strains formed a strongly supported subclade within the T. asperellum clade in the phylogenetic tree based on rpb2 and MLS (combined multilocus sequence). The diversity of DNA sequences, SPD markers and polypeptides in T. asperellum suggests that further speciation is under way within T. asperellum. MALDI-TOF MS distinguished T. yunnanense from related taxa by UPGMA clustering, but separation between T. asperellum and T. asperelloides was less clear.


Assuntos
Trichoderma/classificação , Técnicas de Tipagem Micológica , Filogenia , Proteoma , Análise de Sequência de DNA , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Trichoderma/citologia , Trichoderma/genética
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