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1.
Hum Vaccin Immunother ; : 1-11, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32530720

RESUMO

Few studies in China focused on serotypes of Streptococcus pneumoniae in patients with invasive pneumococcal disease (IPD). We aimed at investigating the serotype distribution for IPD-causing S. pneumoniae and vaccine coverage among Chinese children and adults. This was a multicenter, observational study to collect S. pneumoniae isolates from normal sterile sites and IPD-related clinical information among children and adults. Serotyping was performed by a Capsule-Quellung reaction test using type-specific antisera. The study collected a total of 300 eligible isolates (pediatric = 148, adult = 152) were serotyped in a central laboratory. The most prevalent serotypes were 19A (20.9%) and 23 F (20.3%) in the pediatric group; 3 (21.7%) and 19 F (11.8%) in the adult group. PCV10 had low-to-moderate serotype coverage rates for children (60.8%) and adults (34.2%). PCV13 and PPV23 had high coverage rates for children (89.9%, 93.2%) and adults (70.4%, 82.9%), respectively, Investigational PCVs including PCV15 and PCV20 had high estimated coverage rates in children (89.9%, 93.9%). The study identified 269 subjects with IPD reported as the primary diagnosis in the medical records. Sepsis (48/136, 35.3%) and pneumonia (48/133, 36.1%) had the highest occurrence in the pediatric and adult groups, respectively. Study findings showed that non-PCV7 S. pneumoniae 19A and 3 were the most prevalent serotypes in Chinese children and adults, respectively. High-valent vaccines had similar coverage rates and may have a greater potential in preventing IPD.

2.
BMC Microbiol ; 20(1): 158, 2020 Jun 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.

3.
Int J Antimicrob Agents ; : 105981, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32330584

RESUMO

Clostridium difficile infection (CDI) is the leading cause of antibiotic-associated diarrhea worldwide. In order to gain a better understanding about the molecular epidemiology of C. difficile in Beijing, China, we performed molecular typing, antimicrobial susceptibility test, and drug resistance gene sequencing on 174 C. difficile strains collected from four large tertiary hospitals in Beijing. A total of 31 sequence types (STs) were identified among the 174 strains, of which ST81 was found to be the most prevalent clone, accounting for 26.4% (46/174) of the isolates, followed by ST2 (16.7%, 29/174) and ST54 (9.8%, 17/174). All the isolates were susceptible to metronidazole and vancomycin. The test strains displayed resistance rates of 97.1%, 44.3%, and 44.3% for ciprofloxacin, levofloxacin, and moxifloxacin, respectively. The ST81 isolates displayed a drug resistance rate of 97.8% for the antibiotics levofloxacin and moxifloxacin, which was significantly higher than the rates of the ST2 (0%), ST54 (17.6%), and ST42 (0%) isolates (P<0.05). An amino acid mutation, T82I, was identified in GyrA and the total mutation rate of the C. difficile strains was 40.8% (71/174), while the mutation rate of the ST81 strains was 95.7% (44/46). Three amino acid mutations including D426N, S366A, and D426V were identified in GyrB and the total mutation rate of GyrB was 39.1%. The double-site mutation in GyrB, S366A+D426V was identified in all the ST81 (n=46) strains. In conclusion, the C. difficile ST81 clone showed high levels of fluoroquinolone resistance in Beijing, China, thus highlighting the need for nationwide surveillance of CDI.

4.
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.

5.
J Infect Dis ; 221(Supplement_2): S139-S147, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32176789

RESUMO

BACKGROUND: Candidemia is the most common, serious fungal infection and Candida antifungal resistance is a challenge. We report recent surveillance of candidemia in China. METHODS: The study encompassed 77 Chinese hospitals over 3 years. Identification of Candida species was by mass spectrometry and DNA sequencing. Antifungal susceptibility was determined using the Clinical and Laboratory Standards Institute broth microdilution method. RESULTS: In total, 4010 isolates were collected from candidemia patients. Although C. albicans was the most common species, non-albicans Candida species accounted for over two-thirds of isolates, predominated C. parapsilosis complex (27.1%), C. tropicalis (18.7%), and C. glabrata complex (12.0%). Most C. albicans and C. parapsilosis complex isolates were susceptible to all antifungal agents (resistance rate <5%). However, there was a decrease in voriconazole susceptibility to C. glabrata sensu stricto over the 3 years and fluconazole resistance rate in C. tropicalis tripled. Amongst less common Candida species, over one-third of C. pelliculosa isolates were coresistant to fluconazole and 5-flucytocine, and >56% of C. haemulonii isolates were multidrug resistance. CONCLUSIONS: Non-albicans Candida species are the predominant cause of candidemia in China. Azole resistance is notable amongst C. tropicalis and C. glabrata. Coresistance and multidrug resistance has emerged in less common Candida species.

6.
J Microbiol Immunol Infect ; 53(1): 125-132, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29844003

RESUMO

BACKGROUND: To investigate the in vitro antifungal susceptibilities of 25 genetically confirmed Aspergillus species collected from Taiwan and Mainland China. METHODS: A total of 390 non-duplicate and consecutive Aspergillus isolates representing of 25 species recovered from clinical sources at two teaching hospitals in Taiwan and Mainland china were preserved for this study. In vitro antifungal susceptibility testing (AFST) of those Aspergillus isolates against seven antifungal agents was performed using Sensititre YeastOne (SYO) system. The susceptibility profiles of isolates were analyzed according to the general interpretation code drawn from the SYO instruction. The CYP51A gene sequencing analysis was performed for triazole-resistant Aspergillusfumigatus isolates. RESULTS: Among the 390 Aspergillus isolates, 76.7% (n = 299) exhibited complete susceptibility to all the tested antifungals, and 23.3% (91/390) of different Aspergillus species isolates showed resistance to one or two classes of antifungal agents with higher minimum inhibitory concentrations (MICs) of >2 mg/L. Resistance to amphotericin B was found in 91.2% (83/91) of those less susceptible isolates and most of them focused on species being resistant to Amphotericin B innately. The total rate of triazole resistance in this study was low (3.3%, 13/390), and only 3 (2.8%) A. fumigatus isolates were resistant to at least one of the triazoles with mutations of TR34/L98H or TR46/Y121F/T289A in CYP51A gene. The echinocandins were highly potent to the tested Aspergillus isolates. CONCLUSION: The existence of triazole resistance among A. fumigatus isolates in Taiwan and Mainland China indicates the need for continuous monitoring from now on.

7.
Int J Med Microbiol ; 310(1): 151357, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31570247

RESUMO

Understanding the evolutionary path of M. catarrhalis from macrolide-susceptible to macrolide-resistant organism, is important for hindering macrolide resistance from propagation. Multilocus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE) and whole genome SNP typing (WGST), as useful and practical typing tools, have both advantages and disadvantages. We studied the utility of these 3 typing methods, including the level of agreement, consistency and drawbacks, in characterizing M. catarrhalis clones and clonal complexes. We focused on four clonal complexes [CC224, CC363, CC449 (CCN10) and CC446 (CCN08)] and found that PFGE and WGST had a high level of agreement and a proper consistency of the same clone or very closely related clones, while MLST is less discriminatory for different clones. Furthermore, we also established an evolutionary distance cut-off value for "The same clone". Moreover, we detected macrolide-resistant M. catarrhalis in CC224, which had previously been considered as a macrolide-susceptible clonal complex. A higher number of isolates belonged to ST215 compared to ST446, implying that ST215 is more likely to be the primary founder. Our study also demonstrated that all the four clonal complexes belong to the M. catarrhalis lineage 1, which is considered to be related to increased virulence potential and serum resistance. We also observed that copB II was highly related to CC449 and LOS type B was mainly confined in CC224. In conclusion, these findings provide further insight into the evolutionary characteristics of M. catarrhalis.

8.
Infect Drug Resist ; 12: 3641-3651, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31819547

RESUMO

Introduction: As participants of the national China Hospital Invasive Fungal Surveillance Net program, we sought to describe the epidemiology and antifungal susceptibility patterns of yeast isolates obtained from patients with invasive fungal infection at the First Affiliated Hospital of Zhengzhou University, China. Methods: A total of 434 yeast isolates recovered from blood and other sterile body fluids were identified to species by matrix-assisted laser desorption ionization -time of flight mass spectrometry with or without supplementation by DNA sequencing. Antifungal susceptibilities were determined by Sensititre YeastOneTM YO10 methodology. Results: Candida albicans was the most common causative species (33.9% of isolates) but significantly decreased in frequency from 37.2% to 27.7% from 2012 to 2014. C. tropicalis was the next most common pathogen (25.1%), followed by C. parapsilosis complex (17.3%), C. glabrata (9%), and C. pelliculosa (6.7%), with other species comprising 8% of isolates. Caspofungin, micafungin, and anidulafungin exhibited potent in vitro activities against the majority of Candida isolates. Azoles demonstrated in vitro activities against C. albicans with a susceptibility rate of >95% and against C. parapsilosis complex, >95% isolates were susceptible. Among C. tropicalis and C. glabrata isolates, resistance rates to fluconazole and voriconazole were 11.9%, 9.1% and 7.7%, 28.2%, respectively. Of note, C. pelliculosa had a high incidence rate in newborns and high rates of resistance to fluconazole and voriconazole of 55.2% and 41.4%, respectively. Conclusion: The present study provided valuable local surveillance data on the epidemiology and antifungal susceptibilities of invasive yeast species, which is essential for guiding antifungal treatment protocol development.

9.
Emerg Microbes Infect ; 8(1): 1619-1625, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31711370

RESUMO

Echinocandin resistance in Candida glabrata poses a serious clinical challenge. The underlying resistance mechanism of a pan-echinocandin-resistant C. glabrata isolate (strain L74) was investigated in this study. FKS mutants carrying specific mutations found in L74 were reconstructed by the Alt-R CRISPR-Cas9 system (Fks1 WT/Fks2-E655K, strain CRISPR 31) and site-directed mutagenesis (strain fks1Δ/Fks2-E655K). Sequence analysis of strain L74 revealed a premature stop codon W508stop in FKS1 and an E655K mutation preceding the hotspot 1 region in FKS2. Introduction of the Fks2-E655K mutation in ATCC 2001 (strain CRISPR 31) conferred a modest reduction in susceptibility. However, the same FKS2 mutation in the fks1Δ background (strain fks1Δ/Fks2-E655K) resulted in high levels of resistance to echinocandins. Glucan synthase isolated from L74 was dramatically less sensitive to micafungin (MCF) relative to ATCC 2001. Both FKS1/FKS2 transcript ratios and Fks1/Fks2 protein ratios were significantly lower in L74 and fks1Δ/Fks2-E655K compared to ATCC 2001 and CRISPR 31 (P <0.05). Mice challenged with CRISPR 31 and fks1Δ/Fks2-E655K mutants failed to respond to MCF. In conclusion, the high-level of echinocandin resistance in the clinical isolate of C. glabrata L74 was concluded to result from the combination of null function of Fks1 and the point mutation E655K in Fks2.


Assuntos
Antifúngicos/farmacologia , Candida glabrata/enzimologia , Candidíase/microbiologia , Farmacorresistência Fúngica , Equinocandinas/farmacologia , Proteínas Fúngicas/metabolismo , Glucosiltransferases/metabolismo , Animais , Candida glabrata/efeitos dos fármacos , Candida glabrata/genética , Feminino , Proteínas Fúngicas/genética , Glucosiltransferases/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana
10.
Int J Mol Sci ; 20(16)2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31408937

RESUMO

Wilms tumor 1 (WT1) oncoprotein is an intracellular oncogenic transcription factor which is barely expressed in normal adult tissues but over expressed in a variety of leukemias and solid cancers. WT1-derived HLA-A*02:01 T cell epitope, RMFPNAPYL (RMF), is a validated target for T cell-based immunotherapy. We generated two T cell receptor mimic antibody-drug conjugates (TCRm-ADCs), ESK-MMAE, and Q2L-MMAE, against WT1 RMF/HLA-A*02:01 complex with distinct affinities, which mediate specific antitumor activity. Although ESK-MMAE showed higher tumor growth inhibition ratio in vivo, the efficacy of them was not so promising, which might be due to low expression of peptide/HLA targets. Therefore, we explored a bispecific TCRm-ADC that exerted more potent tumor cytotoxicity compared with TCRm-ADCs. Hence, our findings validate the feasibility of the presenting intracellular peptides as the targets of ADCs, which broadens the antigen selection range of antibody-based drugs and provides new strategies for precision medicine in tumor therapy.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Imunoconjugados/uso terapêutico , Neoplasias Renais/tratamento farmacológico , Proteínas WT1/imunologia , Tumor de Wilms/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Antígenos HLA-A/imunologia , Humanos , Neoplasias Renais/imunologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Receptores de Antígenos de Linfócitos T/imunologia , Tumor de Wilms/imunologia
11.
BMC Infect Dis ; 19(1): 730, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31429713

RESUMO

BACKGROUND: Solobacterium moorei, the only species in the genus Solobacterium, is a Gram-positive, non-spore-forming, strict anaerobic, short to long bacillus. It has rarely been documented to cause blood stream infections. Here we report the first case of bacteremia caused by S.moorei in China. CASE PRESENTATION: A 61-year-old male presented to Peking Union Medical College Hospital (Beijing) with thrombotic thrombocytopenic purpura (TTP) and several other underlying diseases. He also had persistent coma accompanied by intermittent convulsions, halitosis, and intermittent fever. Blood cultures taken when the patient had a high fever were positive, with the anaerobic bottle yielding an organism identified as S.moorei by 16S rRNA gene sequencing, whilst the aerobic bottle grew Streptococcus mitis. After replacement of venous pipeline, and empirical use of vancomycin and meropenem, the patient's body temperature and white blood cell count returned to normal. Unfortunately, the patient died of severe TTP. CONCLUSION: This is the first case report of S. moorei isolation from blood stream in China. 16S rRNA gene sequencing is the only method that can identify S. moorei. Blood cultures must be taken before administration of antibiotics, and anaerobic culture should be considered for such rare pathogens in patients with oral diseases and immune deficiency.


Assuntos
Bacteriemia/microbiologia , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/patogenicidade , Infecções por Bactérias Gram-Positivas/microbiologia , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , China , Bactérias Gram-Positivas/genética , Bactérias Gram-Positivas/isolamento & purificação , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Halitose/etiologia , Halitose/microbiologia , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Púrpura Trombocitopênica Trombótica/complicações , RNA Ribossômico 16S/genética
12.
Artigo em Inglês | MEDLINE | ID: mdl-31157176

RESUMO

Background: Rapid screening of patients for colonization with carbapenemase-producing organisms (CPO), coupled with implementation of infection prevention strategies, has the potential to contain the spread of CPO. Methods: We first evaluated the performance of Xpert Carba-R assay (in comparison with other phenotypic methods) for carbapenemase detection using clinical isolates, and then used it to determine the intestinal CPO colonization in hospitalized patients. We then assessed the effectiveness of patient isolation in controlling the spread of CPO in a medical intensive care unit. Results: The Xpert Carba-R assay required the least processing time to reveal results and showed a 94.5% sensitivity and specificity in carbapenemase detection, except for IMP-8 (n = 4). During a 6-month study period, 134 patients in one ward were studied for CPO colonization and infection. Fifteen patients (11.2%) were colonized by CPO as detected by Xpert Carba-R assay, including three NDM, three IMP, and nine KPC possessing strains. The overall colonization and CPO infection rates were both 11.2% each. Isolation of patients with CPO led to a reduction in both colonization (from 28.6 to 5.6%) and infection rates (from 35.7 to 2.8%) during the study period (p < 0.05). Conclusion: Active surveillance of CPO utilizing the Xpert Carba-R assay supplemented with immediate patient isolation, proved to be an effective strategy to limit the spread of CPO in a health care setting.


Assuntos
Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Técnicas Bacteriológicas/métodos , Isolamento de Pacientes , Conduta Expectante/métodos , beta-Lactamases/isolamento & purificação , beta-Lactamases/metabolismo , Proteínas de Bactérias/genética , Assistência à Saúde , Testes Diagnósticos de Rotina , Feminino , Bactérias Gram-Negativas/genética , Bactérias Gram-Negativas/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular/métodos , Sensibilidade e Especificidade , beta-Lactamases/genética
13.
Infect Drug Resist ; 12: 865-875, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31114266

RESUMO

Introduction: We studied the species distribution and antifungal susceptibilities of Candida isolates causing refractory or recurrent oropharyngeal candidiasis (OPC) in a multicenter study in China (2013-2016). Methods: Species identification was performed using the Bruker Biotyper (Bruker Daltonics, Germany) matrix-assisted laser desorption/ionization time of flight mass spectrometry system supplemented by internal transcribed spacer sequencing as required. Antifungal susceptibilities were determined by the Clinical and Laboratory Standards Institute document (CLSI) M27-A3 broth microdilution methodology. Results: A total of 558 non-duplicate Candida isolates comprising 10 species were obtained from 535 patients. Candida albicans was the most common species (89.6%), followed by C. glabrata (5.2%), C. tropicalis (2.9%), and C. parapsilosis (0.7%). Azoles were active against C. albicans with susceptibility rates of 96% and 95.8% for fluconazole and voriconazole, respectively. MIC50 values of C. albicans to fluconazole, voriconazole, itraconazole, and miconazole were 1, 0.03, 0.25 and 0.12 µg/mL, respectively, higher than those in previous studies of which OPC patients (corresponding MIC50 values of 0.25 , 0.015 , 0.06 , and 0.03 µg/mL). Except for itraconazole, the MIC50 and MIC90 values of 58 non-C. albicans to other azoles were two to threefold higher than C. albicans. Miconazole, amphotericin B, nystatin, and 5-flucytosine had good in vitro antifungal activity for all isolates. Conclusion: The study provides valuable data on the species distribution and antifungal susceptibility of oropharyngeal Candida isolates from geographically diverse areas of China. C. albicans remains the most common species but with increasing rates of azoles resistance.

14.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 41(2): 242-247, 2019 Apr 28.
Artigo em Chinês | MEDLINE | ID: mdl-31060681

RESUMO

Objective To explore the clinical and laboratory characteristics and the prognosis of disseminated non-tuberculous mycobacteria(NTM)diseases in human immunodeficiency virus(HIV)negative patients. Methods Cases of disseminated NTM disease were retrospectively collected in Peking Union Medical College Hospital from January 2012 to October 2018.Clinical manifestations,laboratory findings,treatment,and prognosis of these cases were retrieved from the electronic medical record system. Results Among the 23 HIV negative patients with disseminated NTM disease,21 had underlying diseases,with rheumatoid immune disease(n=7)as the most common one.The main clinical manifestation was fever(n=23).Laboratory tests showed anemia [hemoglobin(85.78±25.47)g/L],hypoalbuminemia [albumin 29(27-32)g/L],elevated erythrocyte sedimentation rate [(85.73±43.78)mm/h] and hypersensitive C-reactive protein [(112.00±70.90)mg/L],and reduction of lymphocyte count [0.69(0.29-2.10)×10 9/L].Lymphocyte subset analysis indicated reduction in CD4 + T cells [213(113-775)/µl],CD8 + T cells [267(99-457)/µl],B cells [39(4-165)/µl],and NK cells [88(32-279)/µl] and elevation of human leukocyte antigen-D related(HLA-DR),and CD38 expression in CD8 + T cells [HLA-DR +CD8 +/CD8 +,60(40-68)%;CD38 +CD8 +/CD8 +,81(65-90)%].The most common species of NTM was Mycobacterium intracellular(n=6).Lymphocyte,CD8 + T cell,B cell,and NK cell counts were significantly lower in dead patients than surviving patients(P =0.045,P=0.045,P=0.032,and P=0.010,respectively). Conclusions Disseminated NTM disease in HIV negative patients is mainly manifested as fever,anemia,hypoalbuminemia,and elevated inflammatory indicators.It is more likely to occur in immunocompromised patients.Patients with decreased lymphocytes,CD8 + T cells,B cells and NK cells tend to have a poor prognosis.


Assuntos
Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium não Tuberculosas/patologia , Anemia , Linfócitos B , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Febre , Soronegatividade para HIV , Humanos , Hipoalbuminemia , Células Matadoras Naturais , Prognóstico , Estudos Retrospectivos
15.
Biosens Bioelectron ; 135: 200-207, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31026774

RESUMO

This paper describes an integrated microfluidic SlipChip device for rapid antimicrobial susceptibility testing (AST) of bloodstream pathogens in positive blood cultures. Unlike conventional AST methods, which rely on an overnight subculture of positive blood cultures to obtain isolated colonies, this device enables direct extraction and enrichment of the bacteria from positive blood cultures by dielectrophoresis. SlipChip technology enables parallel inoculation of the extracted bacteria into nanoliter-scale broth droplets to perform multiplexed ASTs simultaneously. The nanoliter confinement in the droplets increases the effective inoculation amount of the bacteria, shortens the diffusion distance of nutrient elements and gases, and allows faster growth and proliferation rates. Entropy-based image analysis used for the characterization of bacterial susceptibility patterns eliminates the requirement for single-cell morphological analysis and fluorescence labeling. As a proof-of-concept, the susceptibility patterns of Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 6538p, and a positive blood culture containing Escherichia coli against several broad-spectrum antibiotics were determined by the SlipChip device. The on-chip AST results were well matched with those respectively reported by the broth microdilution method and a BD Phoenix Automated Microbiology System. Reliable AST results can be reported to clinicians within 3-8 h using this simple device after positive blood culture, allowing earlier proper administration of antimicrobial therapy.


Assuntos
Antibacterianos/farmacologia , Dispositivos Lab-On-A-Chip , Testes de Sensibilidade Microbiana/instrumentação , Técnicas Biossensoriais/instrumentação , Desenho de Equipamento , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Infecções por Escherichia coli/sangue , Infecções por Escherichia coli/tratamento farmacológico , Humanos , Infecções Estafilocócicas/sangue , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
16.
J Microbiol Immunol Infect ; 52(3): 433-442, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30827858

RESUMO

OBJECTIVE: To investigate the occurrence of vancomycin-resistant enterococci (VRE) isolated from patients in Peking Union Medical College Hospital, Beijing, China from 2011 to 2017, and to evaluate their resistance mechanisms and genetic relatedness. METHODS: All isolates were identified using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF). Antibiotic susceptibility testing was performed using the broth microdilution method. Molecular characterization were detected by PCR and sequencing. Genotyping of VRE isolates was performed by multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE) analysis. Virulence genes were detected by multiplex PCR. RESULTS: A total of 87 consecutive VRE were collected, including 84 isolates of vancomycin resistant Enterococcus faecium (VREfm) and 3 isolates of Enterococcus faecalis (VREfs). Urine (40.2%, 35/87) and blood (17.2%, 15/87) were the most commonly specimens. All VREfm isolates were resistant to ampicillin, and were susceptible to daptomycin, linezolid and tigecycline. The resistant rate of teicoplanin was 47.6%. All of the VREfm isolates carried the vanA gene, no isolates carried vanB. 11.9% (10/84) VREfm isolates carried both vanA and vanM. Among them, 76.2% (64/84) and 66.7% (56/84) carried esp and hyl, respectively. The 3 vancomycin resistant E. faecalis (VREfs) isolates were varied, and only one carried vanB. A total of 3 and 18 STs were detected among VREfs and VREfm strains, respectively. PFGE results indicated a genetic diversity among VREfm isolates. CONCLUSION: This study confirms that VREfm isolates associated with ST78 were the main epidemic lineage responsible for nosocomial infections in China, as were also observed in other nations worldwide.


Assuntos
Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Infecções por Bactérias Gram-Positivas/epidemiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Enterococos Resistentes à Vancomicina/genética , Enterococos Resistentes à Vancomicina/isolamento & purificação , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Pequim/epidemiologia , DNA Bacteriano/genética , Enterococcus faecalis/classificação , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/genética , Enterococcus faecalis/isolamento & purificação , Enterococcus faecium/classificação , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/genética , Enterococcus faecium/isolamento & purificação , Variação Genética , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Tipagem Molecular , Reação em Cadeia da Polimerase Multiplex , Centros de Atenção Terciária , Resistência a Vancomicina/genética , Enterococos Resistentes à Vancomicina/classificação , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Fatores de Virulência/genética
17.
J Microbiol Immunol Infect ; 52(3): 456-464, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30772212

RESUMO

BACKGROUND AND PURPOSE: Bacteroides fragilis group isolates are most frequently isolated anaerobic pathogens. This study aimed to evaluate the accuracy of VITEK MS, Clin-ToF-II MS, Autof MS 1000 and VITEK 2 ANC card on the identification of clinical B. fragilis group isolates, as well as to determine their antimicrobial susceptibilities. METHODS: A total of 138 isolates of B. fragilis group isolates were identified with the three MALDI-TOF MS systems and VITEK 2 ANC cards. 16S rRNA gene sequencing was used as the reference identification method for comparison. Antimicrobial susceptibilities were determined by agar dilution method to 19 antimicrobial agents recommended by Clinical and Laboratory Standards Institute (CLSI). RESULTS: Hundred thirty three isolates of Bacteroides spp. and 5 isolates of Parabacteroides spp. were identified by 16S rRNA sequencing. The rates of accurate identification at species level of VITEK MS, Clin-ToF-II MS, Autof MS 1000 and VITEK 2 ANC card were 94.2%, 94.2%, 98.6% and 94.9%, respectively, while that at genus level were 99.3%, 100%, 100% and 97.8%, respectively. Metronidazole and chloramphenicol were the most susceptible agents (99.3% and 92.8%, respectively), followed by meropenem, ertapenem, imipenem and piperacillin/tazobactam to which the susceptible rates ranged from 76.8% to 79.0%. The susceptible rates to carbapenems decreased 12.4-15.3% from 2010-2013 to 2014-2017. CONCLUSION: All the four systems provided high accurate rate on the identification of B. fragilis group isolates. Metronidazole showed highest activity against these isolates. Attention should be paid to the higher resistant rates to carbapenems, clindamycin, moxifloxacin and tigecycline than the other countries.


Assuntos
Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana/métodos , Infecções por Bacteroides/microbiologia , Bacteroides fragilis/efeitos dos fármacos , Bacteroides fragilis/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Bacteroides fragilis/classificação , Bacteroides fragilis/genética , Bacteroidetes/classificação , Bacteroidetes/efeitos dos fármacos , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Hemocultura , Farmacorresistência Bacteriana/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
19.
J Microbiol Immunol Infect ; 52(4): 604-611, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29191475

RESUMO

BACKGROUND: The aim of this study was to investigate the performance of the Bruker Biotyper matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and Vitek MS systems for identification of genetically-confirmed blood isolates of Candida tropicalis that had been grown on several types of culture media commonly used for primary fungal isolation. METHODS: Isolates included 105 from the National China Hospital Invasive Fungal Surveillance Net program (CHIF-NET) and 120 from National Taiwan University Hospital (NTUH). Culture media tested for CHIF-NET isolates included trypticase soy agar supplemented with 5% sheep blood (BAP), Sabouraud dextrose agar (SDA-C), CHROMagar, China blue agar (CBA), chocolate agar supplemented with vancomycin (CAP-VA), and MacConkey agar (MAC). Culture media used for NTUH isolates included BAP, SDA, CHROMagar, eosin methylene blue (EMB), inhibitory mold agar (IMA), Mycosel agar, and cornmeal agar (CMA). RESULTS: The Bruker Biotyper correctly identified all CHIF-NET isolates to the species level on all six agar media tested and correctly identified the majority of NTUH isolates with the exception of isolates grown on SDA (85.8%) and CMA (52.5%). The Vitek MS system correctly identified all CHIF-NET isolates to the species level with the exception of isolates grown on CHROMagar (84.8%), and correctly identified the majority of NTUH isolates with the exception of isolates grown on SDA (51.7%), Mycosel agar (57.5%), and CMA (9.2%) for NTUH isolates. CONCLUSION: Clinical microbiologists should be aware that different culture media can affect the performance of the Bruker Biotyper MALDI-TOF MS and Vitek MS systems in identifying C. tropicalis.


Assuntos
Candida tropicalis/isolamento & purificação , Meios de Cultura/química , Técnicas de Tipagem Micológica/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Ágar , Candida tropicalis/genética , Candida tropicalis/crescimento & desenvolvimento , China , DNA Fúngico , Fungos/isolamento & purificação , Humanos , Análise de Sequência de DNA , Taiwan
20.
J Med Virol ; 91(3): 351-360, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30267587

RESUMO

OBJECTIVE: This study was performed to determine the antigenic and genetic characteristics and evaluate potential vaccine efficacy of influenza A (H1N1)pdm09 in Yantai from August 2009 to August 2017. MATERIALS AND METHODS: A total of 10 236 swabs were collected among patients with an influenza-like illness who were admitted to two sentinel surveillance hospitals in Yantai, East China, from August 2009 to August 2017. All specimens were cultured in Madin-Darby canine kidney cells and identified by haemagglutination-inhibition assay. Complete sequences of haemagglutinin (HA) and neuraminidase of 51 influenza A(H1N1)pdm09 strains circulating in Yantai were amplified, sequenced and analysed using molecular and phylogenetic methods. The potential vaccine efficacy was calculated using the p epitope model which measured the antigenic variation based on the changes in the dominant epitope of HA. RESULTS: The results showed that most Yantai strains were grouped into genetic clades 1.7, 6C, 6B.1 and 6B.2. The amino acid substitutions accumulated gradually in HA proteins and considerable genetic variation were observed in circulating A(H1N1)pdm09 viruses during the seven influenza seasons. The V241I, N369K, N386K and K432E mutations which may change the binding pattern and affinity of oseltamivir for neuraminidase were detected in the strains circulating in 2016/2017 and 2017/2018 seasons and the recommended vaccine strains could afford optimal protection against the influenza A/H1N1pdm09. CONCLUSIONS: Although influenza A(H1N1)pdm09 viruses acquired significant genetic variation over the course of seven influenza seasons, the recommended vaccine strains still afforded protection against main circulating strains. Continuous epidemiological and virological surveillance are necessary.


Assuntos
Variação Antigênica , Antígenos Virais/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/epidemiologia , Substituição de Aminoácidos , Antígenos Virais/imunologia , China/epidemiologia , Epitopos/imunologia , Evolução Molecular , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Filogenia , RNA Viral/genética , Estações do Ano , Vigilância de Evento Sentinela , Potência de Vacina
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