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1.
J Microbiol Immunol Infect ; 55(2): 282-290, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33839057

RESUMO

BACKGROUND/PURPOSE: There are limited studies on species distribution and susceptibility profiles of Aspergillus strains isolated from patients with otomycosis in China. METHODS: A total of 69 confirmed Aspergillus species isolates were obtained from ear swabs of patients diagnosed with otomycosis from 2017 to 2018 in northern China. Identification of these Aspergillus isolates at the species level was performed using conventional morphological methods and MALDI-TOF MS in combination with molecular sequencing, and in vitro susceptibility to nine antifungal agents was evaluated using the Sensititre YeastOne system. RESULTS: The Aspergillus section Nigri had the greatest distribution of Aspergillus isolates. A. welwitschiae (n = 25) was the most predominant isolate in section Nigri, followed by A. tubingensis (n = 12) and A. niger (n = 11). Other Aspergillus species were also isolated, including A. terreus (n = 11), A. flavus/A. oryzae (n = 8), and A. fumigatus (n = 2). Amphotericin B, posaconazole, and echinocandins were highly in vitro active against all the isolates tested. 2.9% (2/69) of the isolates were resistant to azoles in our study, including one A. niger isolate with a high MIC value for itraconazole (ITR) (16 mg/L) and one A. tubingensis isolate cross-resistant to both voriconazole (VOR) (MIC >8 mg/L) and ITR (MIC >16 mg/L). One A. welwitschiae and one A. niger isolate both had increased MIC values of 4 mg/L against VOR. CONCLUSIONS: A. welwitschiae was the most prevalent Aspergillus species isolated from patients with otomycosis. Our findings also indicated that the azole-resistant Aspergillus section Nigri should be utilized to guide clinical medication for Otomycosis.


Assuntos
Aspergilose , Otomicose , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Aspergilose/microbiologia , Aspergillus , Azóis , Humanos , Itraconazol/uso terapêutico , Testes de Sensibilidade Microbiana , Otomicose/microbiologia , Voriconazol/uso terapêutico
2.
Front Cell Infect Microbiol ; 11: 739496, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34778103

RESUMO

Diutina catenulata (Candida catenulata) is an ascomycete yeast species widely used in environmental and industrial research and capable of causing infections in humans and animals. At present, there are only a few studies on D. catenulata, and further research is required for its more in-depth characterization and analysis. Eleven strains of D. catenulata collected from China Hospital Invasive Fungal Surveillance Net (CHIF-NET) and the CHIF-NET North China Program were identified using matrix-assisted laser desorption ionization-time of flight mass spectrometry and internal transcribed spacer sequencing. The antifungal susceptibility of the Diutina catenulata strains was tested using the Clinical and Laboratory Standards Institute broth microdilution method and Sensititre YeastOne™. Furthermore, ERG11 and FKS1 were sequenced to determine any mutations related to azole and echinocandin resistance in D. catenulata. All isolates exhibited low minimum inhibitory concentration (MIC) values for itraconazole (0.06-0.12 µg/ml), posaconazole (0.06-0.12 µg/ml), amphotericin B (0.25-1 µg/ml), and 5-flucytosine (range, <0.06-0.12 µg/ml), whereas four isolates showed high MICs (≥4 µg/ml) for echinocandins. Strains with high MIC values for azoles showed common ERG11 mutations, namely, F126L/K143R. In addition, L139R mutations may be linked to high MICs of fluconazole. Two amino acid alterations reported to correspond to high MIC values of echinocandin, namely, F621I (F641) and S625L (S645), were found in the hot spot 1 region of FKS1. In addition, one new amino acid alteration, I1348S (I1368), was found outside of the FKS1 hot spot 2 region, and its contribution to echinocandin resistance requires future investigation. Diutina catenulata mainly infects patients with a weak immune system, and the high MIC values for various antifungals exhibited by these isolates may represent a challenge to clinical treatment.


Assuntos
Antifúngicos , Farmacorresistência Fúngica , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida , Humanos , Testes de Sensibilidade Microbiana , Saccharomycetales
3.
Front Cell Infect Microbiol ; 11: 687240, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34295837

RESUMO

Filamentous fungi identification by Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been challenging due to the lack of simple and rapid protein extraction methods and insufficient species coverage in the database. In this study, we created two rapid protein extraction methods for filamentous fungi: a one-step zirconia-silica beads method (ZSB) and a focused-ultrasonication method (FUS). The identification accuracy of two methods were evaluated with the VITEK MS, as well as number of spectra peaks and signal-to-noise ratio (S/N) with M-Discover 100 MALDI-TOF MS compared to the routine method. The better method was applied to build a filamentous fungi in-house spectra library for the M-Discover 100 MS, and then another one and routine method were performed in parallel to verify the accuracy and commonality of the in-house library. Using the two optimized methods, the dedicated operating time before MALDI-TOF MS analysis was reduced from 30 min to 7 (ZSB) or 5 (FUS) min per sample, with only a few seconds added for each additional strain. And both two methods identified isolates from most mold types equal to or better than the routine method, and the total correct identification rate using VITEK MS was 79.67, 76.42, and 76.42%, respectively. On the other hand, the two rapid methods generally achieved higher maximum and minimum S/N ratios with these isolates tested as compared to the routine method. Besides, the ZSB method produced overall mean of maximum and minimum S/N ratio higher than that by FUS. An in-house library of M-Discover MS was successfully built from 135 isolates from 42 species belonging to 18 genera using the ZSB method. Analysis of 467 isolates resulted in 97.22% correctly identified isolates to the species level by the ZSB method versus 95.50% by the routine method. The two novel methods are time- and cost-effective and allow efficient identification of filamentous fungi while providing a simplified procedure to build an in-house library. Thus, more clinical laboratories may consider adopting MALDI-TOF MS for filamentous fungi identification in the future.


Assuntos
Micoses , Fungos , Humanos , Dióxido de Silício , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Zircônio
4.
Front Cell Infect Microbiol ; 11: 648988, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34222036

RESUMO

Immune cells can optimize the management of metabolic resources to balance their energy requirements in order to regulate immune responses. The interconnection between immunometabolism and fungal infections is becoming increasingly apparent. Using proteome and metabolome assays, we found that stimulation of primary human monocytes by Candida albicans was accompanied by upregulation of glucose transporter 3 (GLUT3) and activation of the glycerophospholipid metabolism pathway. Upregulated GLUT3 expression has been preliminarily confirmed in monocytes from patients with C. albicans bloodstream infection. Our findings support the importance of GLUT3 in the complex network of glycerophospholipid metabolism and the innate immune responses against C. albicans. In summary, this study might contribute to decipher the regulatory mechanism between the monocyte metabolic reprogramming and innate immune response and reveal potential targets for the antifungal treatments.


Assuntos
Candida albicans , Imunidade Inata , Glicerofosfolipídeos , Humanos , Metabolismo dos Lipídeos , Monócitos
5.
Int J Antimicrob Agents ; 58(1): 106349, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33905861

RESUMO

Morphologically identified Penicillium (n = 103) and Talaromyces marneffei (n = 8) isolates were collected from various clinical sources between 2016 and 2017 at a medical centre in Beijing, China. Identification to species level was confirmed by sequencing of the internal transcribed spacer (ITS) region, ß-tubulin gene (benA) and RNA polymerase II second largest subunit (RPB2) gene. Of the 111 isolates, 56 (50.5%) were identified as Penicillium spp. and 55 (49.5%) as Talaromyces spp. Eleven species of Penicillium were detected, of which Penicillium oxalicum was the commonest, accounting for 51.8% (29/56), followed by Penicillium rubens (10.7%; 6/56) and Penicillium citrinum (10.7%; 6/56). Among the 55 Talaromyces isolates, nine species were identified, with Talaromyces funiculosus (36.4%; 20/55), Talaromyces stollii (27.3%; 15/55) and Talaromyces marneffei (14.5%; 8/55) being the most common. Of note, 89.3% (50/56) of the Penicillium isolates and 98.2% (54/55) of the Talaromyces isolates exhibited growth at 37°C. The isolates were mainly recovered from patients with pulmonary disorders (56.8%; 63/111), autoimmune disease (12.6%; 14/111) and AIDS (5.4%; 6/111). The azoles and amphotericin B exhibited potent activity against T. marneffei, while various levels of activity were observed against Penicillium and other Talaromyces species The echinocandins had the lowest MECs (MEC90, ≤0.12 mg/L) against most Penicillium and Talaromyces species, with the exception of T. marneffei whose MEC90 (4 mg/L) was five or more dilutions higher than that of the other species tested. These data on the species distribution and antifungal susceptibility expand the current clinical knowledge of Penicillium and Talaromyces species.


Assuntos
Antifúngicos/farmacologia , Pneumopatias/microbiologia , Micoses/microbiologia , Penicillium/efeitos dos fármacos , Talaromyces/efeitos dos fármacos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , China/epidemiologia , DNA Fúngico , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Micoses/tratamento farmacológico , Penicillium/classificação , Penicillium/genética , Prevalência , RNA Polimerase II/genética , Talaromyces/classificação , Talaromyces/genética , Tubulina (Proteína)/genética , Adulto Jovem
6.
J Microbiol Immunol Infect ; 54(1): 17-26, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33153907

RESUMO

Since the initial emergence of coronavirus disease 2019 (COVID-19) in Wuhan, Hubei province, China, a rapid spread of the disease occurred around the world, rising to become an international global health concern at pandemic level. In the face of this medical challenge threatening humans, the development of rapid and accurate methods for early screening and diagnosis of COVID-19 became crucial to containing the emerging public health threat, and prevent further spread within the population. Despite the large number of COVID-19 confirmed cases in China, some problematic cases with inconsistent laboratory testing results, were reported. Specifically, a high false-negative rate of 41% on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) detection by real-time reverse transcription-polymerase chain reaction (qRT-PCR) assays was observed in China. Although serological testing has been applied worldwide as a complementary method to help identify SARS-CoV-2, several limitations on its use have been reported in China. Therefore, the use of both qRT-PCR and serological testing in the diagnosis of COVID-19 in China and elsewhere, presented considerable challenges, but when used in combination, can be valuable tools in the fight against COVID-19. In this review, we give an overview of the advantages and disadvantages of different molecular techniques for SARS-CoV-2 detection that are currently used in several labs, including qRT-PCR, gene sequencing, loop-mediated isothermal amplification (LAMP), nucleic acid mass spectrometry (MS), and gene editing technique based on clustered regularly interspaced short palindromic repeats (CRISPR/Cas13) system. Then we mainly review and analyze some causes of false-negative qRT-PCR results, and how to resolve some of the diagnostic dilemma.


Assuntos
Teste para COVID-19/métodos , COVID-19/diagnóstico , SARS-CoV-2/isolamento & purificação , COVID-19/epidemiologia , COVID-19/virologia , China/epidemiologia , Humanos , Programas de Rastreamento/métodos , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Pandemias , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sensibilidade e Especificidade , Testes Sorológicos/métodos , Carga Viral
7.
BMC Microbiol ; 20(1): 350, 2020 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-33198626

RESUMO

BACKGROUND: Omadacycline (ZL-2401) is a semi-synthetic derivative of minocycline. It has a broadspectrum activity against Gram-positive and Gram-negative bacteria, and atypical pathogens. The objective of this study was to evaluate the antibacterial activity of omadacycline against recently collected bacterial isolates from Chinese patients. RESULTS: Omadacycline showed potent activity against all Gram-positive pathogens: S. aureus MICs were low regardless of susceptibility to methicillin (methicillin-resistant Staphylococcus aureus, MRSA: N = 97, MIC50/90 0.12/0.25 mg/L, 98.5% susceptible; methicillin-sensitive Staphylococcus aureus, MSSA: N = 100, MIC50/90 0.12/0.12 mg/L, 100.0% susceptible). Omadacycline was also very effective against ß-haemolytic streptococci (MIC50/90, 0.06/0.12 mg/L), viridans group streptococci (MIC50/90,<0.03/0. 06 mg/L), and enterococci (MIC50/90, 0.03/0.12 mg/L). Against S. pneumoniae, omadacycline was highly active regardless of penicillin-resistance (MIC90 0.06 mg/L) and despite the fact that less than 10.0% of these strains were susceptible to tetracycline. Omadacycline exhibited good in vitro activity against Enterobacterales isolates (MIC50/90, 2/8 mg/L), inhibiting 81.7% of the isolates at ≤4 mg/L. M. catarrhalis isolates (MIC50/90, 0.12/0.25 mg/L) were fully susceptible to omadacycline at ≤0.5 mg/L. CONCLUSIONS: Omadacycline showed potent in vitro activity against most common bacterial pathogens, and even against highly resistant problem pathogens, such as MRSA, penicillin-R and tetracycline-R S. pneumoniae and enterococci. The susceptibility rate of Chinese isolates was similar to those reported in other countries, but the decreased activity against K. pneumoniae isolates in the present study should be noted.


Assuntos
Antibacterianos/farmacologia , Tetraciclinas/farmacologia , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Infecções Bacterianas/microbiologia , China , Farmacorresistência Bacteriana/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana
8.
BMC Microbiol ; 20(1): 158, 2020 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-32532202

RESUMO

BACKGROUND: To investigate the species distribution of non-tuberculous mycobacteria (NTM) among tuberculosis (TB) specimens collected from January 2013 to December 2018 at Peking Union Medical Hospital (Beijing), China. NTM species identification was carried out by DNA microarray chip. RESULTS: Mycobacterial species were detected in 1514 specimens from 1508 patients, among which NTM accounted for 37.3% (565/1514), increasing from a proportion of 15.6% in 2013 to 46.1% in 2018 (P < 0.001). Among the 565 NTM positive specimens, the majority (55.2%) were from female patients. Furthermore, patients aged 45-65 years accounted for 49.6% of the total patients tested. Among 223 NTM positive specimens characterized further, the majority (86.2%) were from respiratory tract, whilst 3.6 and 3.1% were from lymph nodes and pus, respectively. Mycobacterium intracellulare (31.8%) and Mycobacterium chelonae / Mycobacterium abscessus (21.5%) were the most frequently detected species, followed by M. avium (13.5%), M. gordonae (11.7%), M. kansasii (7.6%), and others. CONCLUSION: The proportion of NTM among mycobacterial species detected in a tertiary hospital in Beijing, China, increased rapidly from year 2013 to 2018. Middle-aged patients are more likely to be infected with NTM, especially females. Mycobacterium intracellulare and Mycobacterium chelonae/ Mycobacterium abscessus were the most frequently detected NTM pathogens. Accurate and timely identification of NTM is important for diagnosis and treatment.


Assuntos
Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Micobactérias não Tuberculosas/classificação , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Adulto , Fatores Etários , China/epidemiologia , DNA Bacteriano/genética , Feminino , Humanos , Linfonodos/microbiologia , Masculino , Pessoa de Meia-Idade , Infecções por Mycobacterium não Tuberculosas/microbiologia , Micobactérias não Tuberculosas/genética , Micobactérias não Tuberculosas/isolamento & purificação , Prevalência , Sistema Respiratório/microbiologia , Estudos Retrospectivos , Supuração/microbiologia , Centros de Atenção Terciária
9.
J Microbiol Immunol Infect ; 53(6): 845-853, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32334978

RESUMO

BACKGROUND/PURPOSE: As the incidence of fungal infections in China increases, the demand for rapid and accurate diagnosis of mycoses is growing. Yet, information on current diagnostic capacity is scarce. METHODS: An online survey was conducted in February 2018 to collect information on mycology testing from tertiary care hospitals across China. Responses from 348 hospitals were analyzed, and a scoring system was designed and employed to assess the overall diagnostic capacity. RESULTS: Most of the surveyed hospitals did not have separate laboratory space, manpower, or equipment dedicated for fungal testing. Conventional staining methods were widely available (>70%), whereas GMS and fluorescent staining were less common. Fungal identification services were offered mostly with chromogenic medium, morphological characterization or automated identification systems, other than more advanced methods such as MALDI-TOF MS and DNA sequencing. Fungal serology testing was available in 81.1%, with G test being the most often used. Though 91.8% of the respondents had the ability to perform antifungal susceptibility testing for yeasts, less than 13% conducted such testing for molds. The percentage of laboratories participating in External Quality Assessment programs and research was 57.5% and 32.5%, respectively. The average score for the 348 surveyed hospitals was 37.2 (out of a maximum of 89 points), with only 15 hospitals scoring >60, suggesting a general lack of high-quality mycology laboratories. CONCLUSIONS: The overall clinical testing capacity for fungal infection in China is insufficient. More investment and training efforts are warranted to establish centers of excellence and promote access to high-quality diagnostic services.


Assuntos
Serviços de Laboratório Clínico/estatística & dados numéricos , Testes Diagnósticos de Rotina/estatística & dados numéricos , Micoses/diagnóstico , China , Humanos , Testes de Sensibilidade Microbiana/estatística & dados numéricos , Técnicas de Tipagem Micológica/estatística & dados numéricos , Micologia/estatística & dados numéricos , Micoses/microbiologia , Sorologia/estatística & dados numéricos , Inquéritos e Questionários
10.
Huan Jing Ke Xue ; 38(5): 2065-2073, 2017 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965115

RESUMO

This study aimed to understand the soil actinobacterial community diversity in the urban and rural hydro-fluctuation zone of the Three Gorges Reservoir region. The hydro-fluctuation zone of Chongqing Great Theatre in Jiangbei District and the Ruxi river basin in Zhong County, Chongqing, was chosen as the study area. Soil samples were collected in June 2015, to measure actinobacterial biodiversity using the terminal-restriction fragment length polymorphism (T-RFLP) molecular method. Results showed that:1 The actinobacterial biodiversity was different in the urban and rural hydro-fluctuation zone after artificial vegetation restoration. The actinobacterial biodiversity of the urban hydro-fluctuation zone was significantly higher than that of the rural hydro-fluctuation zone (P<0.05), which was most obvious in the surface soil. 2 The actinobacterial biodiversity of woodland was higher than that of grassland, but there was no significant difference in the actinobacterial biodiversity among the three soil layers in both the urban and rural hydro-fluctuation zone. 3 The dominant species of actinomycetes was different in different samples. 4 Redundancy analysis and the Monte-Carlo test revealed that water content and available nitrogen (AN) played a critical role in influencing actinobacterial biodiversity in the urban hydro-fluctuation zone (P<0.05). In contrast, the water content, organic matter (OM), available nitrogen (AN) and available phosphorus (AP) played a critical role in influencing actinobacterial biodiversity in the rural hydro-fluctuation zone of the Three Gorges Reservoir region (P<0.05). Thus, we concluded that the actinobacterial biodiversity of the urban hydro-fluctuation zone was significantly higher than that of the rural hydro-fluctuation zone in the Three Gorges Reservoir region, and such a result was attributed to the increased human disturbance and soil nutrients.


Assuntos
Actinobacteria/classificação , Biodiversidade , Rios , Microbiologia do Solo , China , Cidades , Nitrogênio , Fósforo , Solo
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