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1.
J Antimicrob Chemother ; 79(1): 128-133, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37991189

RESUMO

OBJECTIVES: We explored the epidemiological and molecular characteristics of Candida parapsilosis sensu stricto isolates in China, and their mechanisms of azole resistance. METHODS: Azole susceptibilities of 2318 non-duplicate isolates were determined using CLSI broth microdilution. Isolates were genotyped by a microsatellite typing method. Molecular resistance mechanisms were also studied and functionally validated by CRISPR/Cas9-based genetic alterations. RESULTS: Fluconazole resistance occurred in 2.4% (n = 56) of isolates, and these isolates showed a higher frequency of distribution in ICU inpatients compared with susceptible isolates (48.2%, n = 27/56 versus 27.8%, 613/2208; P = 0.019). Microsatellite-genotyping analysis yielded 29 genotypes among 56 fluconazole-resistant isolates, of which 10 genotypes, including 37 isolates, belonged to clusters, persisting and transmitting in Chinese hospitals for 1-29 months. Clusters harbouring Erg11Y132F (5/10; 50%) were predominant in China. Among these, the second most dominant cluster MT07, including seven isolates, characteristically harbouring Erg11Y132F and Mrr1Q625K, lent its carriage to being one of the strongest associations with cross-resistance and high MICs of fluconazole (>256 mg/L) and voriconazole (2-8 mg/L), causing transmission across two hospitals. Among mutations tested, Mrr1Q625K led to the highest-level increase of fluconazole MIC (32-fold), while mutations located within or near the predicted transcription factor domain of Tac1 (D440Y, T492M and L518F) conferred cross-resistance to azoles. CONCLUSIONS: This study is the first Chinese report of persistence and transmissions of multiple fluconazole-resistant C. parapsilosis sensu stricto clones harbouring Erg11Y132F, and the first demonstration of the mutations Erg11G307A, Mrr1Q625K, Tac1L263S, Tac1D440Y and Tac1T492M as conferring resistance to azoles.


Assuntos
Candida parapsilosis , Fluconazol , Fluconazol/farmacologia , Candida parapsilosis/genética , Antifúngicos/farmacologia , Azóis/farmacologia , China/epidemiologia , Testes de Sensibilidade Microbiana , Farmacorresistência Fúngica/genética
2.
J Dairy Sci ; 106(8): 5626-5635, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37291038

RESUMO

Fatty liver is a major metabolic disorder of high-producing dairy cows during the transition period. In nonruminants, it is well established that insulin-induced gene 1 (INSIG1) plays a crucial role in regulating hepatic lipogenesis by controlling the anchoring of sterol regulatory element-binding protein 1 (SREBP-1) on the endoplasmic reticulum along with SREBP cleavage-activating protein (SCAP). Whether the INSIG1-SCAP-SREBP-1c transport axis is affected in cows experiencing fatty liver is unknown. Thus, the aim of this study was to investigate the potential role of INSIG1-SCAP-SREBP-1c axis in the progression of fatty liver in dairy cows. For in vivo experiments, 24 dairy cows at the start of their fourth lactation (median; range 3-5) and 8 d in milk (median; range 4-12 d) were selected into a healthy group [n = 12; triglyceride (TG) content <1%] and a severe fatty liver group (n = 12; TG content >10%) according to their hepatic TG content. Blood samples were collected for detecting serum concentrations of free fatty acids, ß-hydroxybutyrate, and glucose. Compared with healthy cows, cows with severe fatty liver had higher serum concentrations of ß-hydroxybutyrate and free fatty acids and lower concentration of glucose. Liver biopsies were used to detect the status of INSIG1-SCAP-SREBP-1c axis, and the mRNA expression of SREBP-1c-target lipogenic genes acetyl-CoA carboxylase α (ACACA), fatty acid synthase (FASN), and diacylglycerol acyltransferase 1 (DGAT1). Cows with severe fatty liver had lower protein expression of INSIG1 in the hepatocyte endoplasmic reticulum fraction, greater protein expression of SCAP and precursor SREBP-1c in the hepatocyte Golgi fraction, and greater protein expression of mature SREBP-1c in the hepatocyte nuclear fraction. In addition, the mRNA expression of SREBP-1c-target lipogenic genes ACACA, FASN, and DGAT1 was greater in the liver of dairy cows with severe fatty liver. In vitro experiments were conducted on hepatocytes isolated from 5 healthy 1-d-old female Holstein calves, and hepatocytes from each calf were run independently. First, hepatocytes were treated with 0, 200, or 400 µM palmitic acid (PA) for 12 h. Exogenous PA treatment decreased INSIG1 protein abundance, enhanced the endoplasmic reticulum to Golgi export of SCAP-precursor SREBP-1c complex and the nuclear translocation of mature SREBP-1c, all of which was associated with increased transcriptional activation of lipogenic genes and TG synthesis. Second, hepatocytes were transfected with INSIG1-overexpressing adenovirus for 48 h and treated with 400 µM PA 12 h before the end of transfection. Overexpressing INSIG1 inhibited PA-induced SREBP-1c processing, upregulation of lipogenic genes, and TG synthesis in hepatocytes. Overall, the present in vivo and in vitro results indicated that the low abundance of INSIG1 contributed to SREBP-1c processing and hepatic steatosis in dairy cows. Thus, the INSIG1-SCAP-SREBP-1c axis may be a novel target for treatment of fatty liver in dairy cows.


Assuntos
Doenças dos Bovinos , Fígado Gorduroso , Bovinos , Animais , Feminino , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Ácidos Graxos não Esterificados , Ácido 3-Hidroxibutírico , Fígado Gorduroso/metabolismo , Fígado Gorduroso/veterinária , Fígado/metabolismo , Hepatócitos/metabolismo , Triglicerídeos/metabolismo , Insulina/metabolismo , RNA Mensageiro/metabolismo , Glucose/metabolismo , Doenças dos Bovinos/metabolismo
3.
J Biomed Sci ; 29(1): 78, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36207707

RESUMO

BACKGROUND: Escherichia coli sequence type (ST)131 is an important urinary tract pathogen, and is responsible for considerable healthcare-associated problems and costs worldwide. A better understanding of the factors that contribute to its rapid worldwide spread may help in arresting its continual spread. We studied a large collection of fecal and urinary E. coli ST131 and E. coli non-ST131 phylogenetic group B2 isolates, from women, men and children, in regional NSW, Australia. RESULTS: We found out that there was a step up in ST131 prevalence (and possibly in virulence) from fecal to clinical (urinary) isolates in general, and specifically among ciprofloxacin resistant isolates, in the 3 host groups. Furthermore, our results revealed that the inferred virulence potential of the ST131 isolates (as measured by VF gene scores) was much higher than that of non-ST131 phylogenetic group B2 isolates, and this was much more pronounced amongst the urinary isolates. This finding suggests presence of possible E. coli phylogenetic B2 subgroups with varying levels of virulence, with ST131 being much more virulent compared to others. A strong association between ST131 and fluoroquinolone (FQ) resistance was also demonstrated, suggesting that FQ use is related to ST131 emergence and spread. Specifically, about 77% of ST131 isolates from women and men, and 47% from children, were extended spectrum ß- lactamase (ESBL) producers. Moreover, FQ resistant ST131 ESBL isolates on average harbored more VF genes than all other isolates. CONCLUSIONS: The strong association between ST131 prevalence and FQ resistance amongst the studied isolates suggests that FQ use is related to ST131 emergence and spread. Furthermore, our results demonstrate that FQ resistance and a plurality of VF genes can exist together in ST131, something that has traditionally been regarded as being inversely related. This may partly contribute to the emergence and worldwide spread of ST131.


Assuntos
Infecções por Escherichia coli , Escherichia coli , Antibacterianos/farmacologia , Criança , Ciprofloxacina , Escherichia coli/genética , Infecções por Escherichia coli/epidemiologia , Feminino , Fluoroquinolonas , Genótipo , Humanos , Filogenia , Prevalência , Virulência/genética , beta-Lactamases/genética
4.
J Biomed Sci ; 29(1): 66, 2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36068602

RESUMO

BACKGROUND: Extraintestinal Escherichia coli (E. coli) causing urinary tract infections (UTIs), and often referred to as uropathogenic E. coli (UPEC), are a major contributor to the morbidity of UTIs and associated healthcare costs. UPEC possess several virulence factors (VFs) for infecting and injuring the host. We studied the papG allele distribution, and its association with other VF genes and phylogenetic groups, amongst 836 UPEC and fecal isolates from reproductive age women. RESULTS: The papGII gene was highly prevalent amongst pyelonephritis isolates (68%), whilst the majority, albeit smaller proportion, of cystitis isolates (31%) harboured the papGIII gene. Among the pyelonephritis and cystitis isolates, papG positive isolates on average had higher VF gene scores, and were more likely to belong to phylogenetic group B2, than their negative counterparts. This was mostly due to the contribution of papGII isolates, which on average contained more VF genes than their papGIII counterparts, irrespective of the uro-clinical syndrome. However, the papGII isolates from the pyelonephritis cohort had higher VF gene scores than the cystitis ones, suggesting presence of possible papGII clones with differing inferred virulence potential. Furthermore, papGII isolates were more likely to possess an intact pap gene operon than their papGIII counterparts. Also of note was the high proportion of isolates with the papGI allele which was not associated with other pap operon genes; and this finding has not been described before. CONCLUSIONS: The association of the papGII gene with several VF genes compared to the papGIII gene, appears to explain the abundance of these genes in pyelonephritis and cystitis isolates, respectively.


Assuntos
Cistite , Infecções por Escherichia coli , Pielonefrite , Infecções Urinárias , Escherichia coli Uropatogênica , Adesinas de Escherichia coli/genética , Alelos , Cistite/genética , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/genética , Feminino , Proteínas de Fímbrias/genética , Humanos , Filogenia , Pielonefrite/genética , Infecções Urinárias/genética , Escherichia coli Uropatogênica/genética , Fatores de Virulência/genética
5.
Microb Pathog ; 150: 104683, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33309685

RESUMO

To explore the role of dryocrassin ABBA (ABBA) in the prevention and treatment of Streptococcus pneumoniae (S. pneumoniae) infections in vitro, a minimal inhibitory concentration test, growth curve assay, hemolysis assay, BacLight LIVE/DEAD staining experiments, oligomerization inhibition assay, time-killing test, LDH release detection assay and cytotoxicity test were performed to evaluate the efficacy of ABBA against S. pneumoniae infections in vitro. The results indicated that ABBA treatment exists bactericidal effect on S. pneumoniae at a concentration of less than 8 µg/ml. Furthermore, ABBA was effective at inhibiting the oligomerization of pneumolysin (PLY) from reducing its hemolytic activity. Meanwhile, ABBA could ameliorate cell injury by neutralizing the biological activity of PLY without cytotoxicity. In summary, ABBA was a leading compound against S. pneumoniae infections through bactericidal effect and neutralizing PLY activity.


Assuntos
Infecções Pneumocócicas , Streptococcus pneumoniae , Proteínas de Bactérias , Compostos de Benzilideno , Cicloexanonas , Humanos , Infecções Pneumocócicas/tratamento farmacológico , Estreptolisinas
6.
BMC Womens Health ; 21(1): 240, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-34116668

RESUMO

BACKGROUND: This study aimed to explore the molecular mechanisms of tibolone treatment in postmenopausal women. METHODS: The gene set enrichment profile, GSE12446, which includes 9 human endometrial samples from postmenopausal women treated with tibolone (tibolone group) and 9 control samples (control group), was downloaded from GEO database for analysis. Differentially expressed genes (DEGs) in tibolone vs. control groups were identified and then used for function and pathway enrichment analysis. Protein-protein interaction (PPI) network and module analyses were also performed. Finally, drug-target interaction was predicted for genes in modules, and then were validated in Pubmed. RESULTS: A total of 238 up-regulated DEGs and 72 down-regulated DEGs were identified. These DEGs were mainly enriched in various biological processed and pathways, such as cilium movement (e.g., CCDC114 and DNAI2), calcium ion homeostasis, regulation of hormone levels and complement/coagulation cascades. PPI network contained 368 interactions and 166 genes, of which IGF1, DNALI1, CCDC114, TOP2A, DNAH5 and DNAI2 were the hue genes. A total of 96 drug-gene interactions were obtained, including 94 drugs and eight genes. TOP2A and HTR2B were found to be targets of 28 drugs and 38 drugs, respectively. Among the 94 obtained drugs, only 12 drugs were reported in studies, of which 7 drugs (e.g., epirubicin) were found to target TOP2A. CONCLUSIONS: CCDC114 and DNAI2 might play important roles in tibolone-treated postmenopausal women via cilium movement function. TOP2A might be a crucial target of tibolone in endometrium of postmenopausal women.


Assuntos
Perfilação da Expressão Gênica , Pós-Menopausa , Biologia Computacional , Endométrio , Feminino , Redes Reguladoras de Genes , Humanos , Proteínas Associadas aos Microtúbulos , Norpregnenos
7.
J Infect Dis ; 221(Suppl 2): S139-S147, 2020 03 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.


Assuntos
Antifúngicos/farmacologia , Azóis/farmacologia , Candida/classificação , Candida/efeitos dos fármacos , Candidemia/epidemiologia , Candidemia/microbiologia , Candida/isolamento & purificação , China , Farmacorresistência Fúngica , Monitoramento Epidemiológico , Hospitais , Humanos , Proteínas de Membrana , Testes de Sensibilidade Microbiana , Análise de Sequência de DNA
8.
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.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Evolução Molecular , Genoma Bacteriano , Genótipo , Moraxella catarrhalis/genética , Adulto , Líquido da Lavagem Broncoalveolar/microbiologia , Criança , Orelha/microbiologia , Eletroforese em Gel de Campo Pulsado , Humanos , Moraxella catarrhalis/classificação , Infecções por Moraxellaceae/microbiologia , Tipagem de Sequências Multilocus , Filogenia , Polimorfismo de Nucleotídeo Único , Escarro/microbiologia
9.
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
10.
Bioorg Med Chem Lett ; 30(16): 127286, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32631508

RESUMO

Natural quinones and their analogues have attracted growing attention because of their novel anticancer activities. A series of novel isothiazoloquinoline quinone analogues were synthesized and evaluated for antitumor activities against four different kind of cancer cells. Among them, isothiazoloquinolinoquinones inhibited cancer cells proliferation effectively with IC50 values in the nanomolar range, and isothiazoloquinolinoquinone 13a induced the cell apoptosis. Further exploration of possible mechanism of action indicates that 13a not only activates ROS production through NQO1-directed redox cycling but also inhibits the phosphorylation of STAT3. These findings indicate that 13a has potential use for the development of new skeleton drug candidate as an efficient substrate of NQO1 and STAT3 inhibitor.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , NAD(P)H Desidrogenase (Quinona)/antagonistas & inibidores , Quinonas/farmacologia , Fator de Transcrição STAT3/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Estrutura Molecular , NAD(P)H Desidrogenase (Quinona)/metabolismo , Oxirredução , Quinonas/síntese química , Quinonas/química , Fator de Transcrição STAT3/metabolismo , Relação Estrutura-Atividade
11.
Appl Opt ; 59(6): 1576-1584, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32225662

RESUMO

The process monitoring of the top side and the evaluation of surface quality were applied in adjustable ring mode (ARM) laser welding of 316 stainless steel by using visual monitoring and confocal sensor technology. Experiments were conducted in different power arrangements of an ARM laser. In this study, the process status was evaluated based on the area of keyhole entrance and the width of the pool. The geometric characteristics of the topside weld were measured by a confocal sensor. The shape of the fusion zone was analyzed based on its cross section. The process mechanism of a different mode of ARM laser welding was investigated by analyzing the process status and geometric characteristics of the surface bead. Experimental results showed that dual-mode laser welding could stabilize the keyhole entrance with a uniform weld surface formation in comparison to the pure ring-mode laser weld. The dual-mode laser also generated a wider molten pool with a wider fusion zone than the pure center laser weld.

12.
J Dairy Sci ; 102(9): 7895-7903, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31279560

RESUMO

The objective of this study was to evaluate dielectric spectra as a means of quantitatively determining total bacterial count (TBC) of raw goat milk. The dielectric spectra, including dielectric constant (ε') spectra and dielectric loss factor (ε″) spectra, and TBC of 154 raw goat milk samples were measured using network analyzer and plate count methods, respectively. Owing to the poor linear relationship between TBC in logarithm and permittivities at a single frequency, chemometrics was used to reduce noise, identify outliers, select effective variables, and divide sample sets. Several linear models, such as multiple linear regression, ridge regression, and least absolute shrinkage and selection operator, were established to determine TBC based on the effective spectra of ε', ε″, and their combination (ε'+ε″). The results indicated that the models built using the spectra of ε'+ε″ and ε' had excellent TBC prediction performance. The best model was multiple linear regression based on ε'+ε″ spectra with the residual predictive deviation of 3.26. This study shows that the dielectric spectra had great potential to quantitatively and rapidly determine TBC of raw milk.


Assuntos
Carga Bacteriana/veterinária , Cabras/microbiologia , Leite/microbiologia , Animais , Espectroscopia Dielétrica/veterinária , Feminino , Modelos Lineares , Leite/química
13.
J Clin Microbiol ; 56(7)2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29743305

RESUMO

Data on the epidemiology of invasive candidiasis (IC) and the antifungal susceptibility of Candida isolates in China are still limited. Here we report on surveillance for IC from the China Hospital Invasive Fungal Surveillance Net (CHIF-NET) study. Sixty-five tertiary hospitals collected 8,829 Candida isolates from 1 August 2009 to 31 July 2014. Matrix-assisted laser desorption ionization-time of flight mass spectrometry supplemented by ribosomal DNA sequencing was used to define the species, and the fluconazole and voriconazole susceptibilities were determined by the Clinical and Laboratory Standards Institute disk diffusion method. A total of 32 Candida species were identified. Candida albicans was the most common species (44.9%), followed by the C. parapsilosis complex (20.0%), C. tropicalis (17.2%), and the C. glabrata complex (10.8%), with other species comprising <3% of isolates. However, in candidemia, the proportion of cases caused by C. albicans was only 32.3%. C. albicans and C. parapsilosis complex isolates were susceptible to fluconazole and voriconazole (<6% resistance), while fluconazole and azole cross-resistance rates were high in C. tropicalis (13.3% and 12.9%, respectively), C. glabrata complex (18.7% and 14%, respectively), and uncommon Candida species (44.1% and 10.3%, respectively) isolates. Moreover, from years 1 to 5 of the study, there was a significant increase in the rates of resistance to fluconazole among C. glabrata complex isolates (12.2% to 24.0%) and to both fluconazole (5.7% to 21.0%) and voriconazole (5.7% to 21.4%) among C. tropicalis isolates (P < 0.01 for all comparisons). Geographic variations in the causative species and susceptibilities were noted. Our findings indicate that antifungal resistance has become noteworthy in China, and enhanced surveillance is warranted.


Assuntos
Antifúngicos/farmacologia , Azóis/farmacologia , Candida/classificação , Candida/efeitos dos fármacos , Candidíase Invasiva/epidemiologia , Candidíase Invasiva/microbiologia , Monitoramento Epidemiológico , China/epidemiologia , Farmacorresistência Fúngica , Hospitais , Humanos , Testes de Sensibilidade Microbiana , Técnicas de Tipagem Micológica
14.
Med Mycol ; 56(7): 816-827, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29228397

RESUMO

No study has comprehensively evaluated the performance of 28S nrDNA and ITS sequencing, commercial biochemical test kits, MALDI-TOF MS platforms, and the emerging rep-PCR DNA fingerprinting technology using a cohort of yeast strains collected from a clinical microbiology laboratory. In this study, using 71 clinically important yeast isolates (excluding Candida albicans) collected from a single centre, we determined the concordance of 28S nrDNA and ITS sequencing and evaluated the performance of two commercial test kits, two MALDI-TOF MS platforms, and rep-PCR DNA fingerprinting. 28S nrDNA and ITS sequencing showed complete agreement on the identities of the 71 isolates. Using sequencing results as the standard, 78.9% and 71.8% isolates were correctly identified using the API 20C AUX and Vitek 2 YST ID Card systems, respectively; and 90.1% and 80.3% isolates were correctly identified using the Bruker and Vitek MALDI-TOF MS platforms, respectively. Of the 18 strains belonging to the Candida parapsilosis species complex tested by DiversiLab automated rep-PCR DNA fingerprinting, all were identified only as Candida parapsilosis with similarities ≥93.2%, indicating the misidentification of Candida metapsilosis and Candida orthopsilosis. However, hierarchical cluster analysis of the rep-PCR DNA fingerprints of these three species within this species complex formed three different discrete clusters, indicating that this technology can potentially differentiate the three species. To achieve higher accuracies of identification, the databases of commercial biochemical test kits, MALDI-TOF MS platforms, and DiversiLab automated rep-PCR DNA fingerprinting needs further enrichment, particularly for uncommonly encountered yeast species.


Assuntos
Candida parapsilosis/isolamento & purificação , Candidíase/diagnóstico , Impressões Digitais de DNA/métodos , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Tipagem Micológica/métodos , Análise de Sequência de DNA/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Candida parapsilosis/química , Candida parapsilosis/classificação , Candida parapsilosis/genética , Candidíase/microbiologia , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Humanos , Reação em Cadeia da Polimerase/métodos , RNA Ribossômico 28S/genética
15.
BMC Infect Dis ; 17(1): 709, 2017 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-29089026

RESUMO

BACKGROUND: Haematobacter massiliensis, a rare species of fastidious Gram-negative, non-motile, non-sporing, non-fermentative, pleomorphic, aerobic bacilli, has rarely been documented as the cause of infectious endocarditis in literature. Here we report the first case of infectious endocarditis (IE) caused by H. massiliensis in China. CASE PRESENTATION: A 44-year-old woman presented to the infectious department of Peking Union Medical College Hospital (Beijing) in August 2013, with a 7-week history of fevers, chills, sore throat, muscular soreness, occasional joint pain, and cough. The organism obtained by blood culture, identified as H. massiliensis by 16S rRNA gene sequencing, was finally implicated as the cause of infectious endocarditis. The patient was cured with amoxicillin/clavulanate combined with amikacin for 6 weeks. CONCLUSION: This is the first case report in China, of the isolation of H. massiliensis from the bloodstream of a patient with endocarditis. The microbiology and clinical study of the organism will help us understand it better in future clinical practice.


Assuntos
Endocardite Bacteriana/diagnóstico , Rhodobacteraceae/isolamento & purificação , Adulto , Amoxicilina/uso terapêutico , China , Ácido Clavulânico/uso terapêutico , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , DNA Bacteriano/metabolismo , Quimioterapia Combinada , Endocardite Bacteriana/tratamento farmacológico , Endocardite Bacteriana/microbiologia , Feminino , Humanos , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/isolamento & purificação , Rhodobacteraceae/genética , Análise de Sequência de DNA , Função Ventricular Esquerda/fisiologia
16.
J Clin Microbiol ; 54(8): 2187-9, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27252461

RESUMO

With molecular sequencing as a gold standard, the Vitek MS, Bruker Biotyper MS, and Vitek-2 Compact systems correctly identified 92.7%, 97.0%, and 15.2% of 164 Candida guillermondii isolates, respectively, and none of 8 C. fermentati isolates. All of the isolates showed high susceptibility to echinocandins, but some C. guilliermondii isolates showed low azole susceptibility.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candida/isolamento & purificação , Candidíase/microbiologia , Adulto , Idoso , China , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade
17.
J Clin Microbiol ; 54(1): 226-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26560541

RESUMO

Forty-two putative Cryptococcus laurentii isolates identified by the Vitek 2 system were collected in China. The gold standard, internal transcribed spacer (ITS) sequencing, confirmed that only two isolates were genuine C. laurentii. Bruker Biotyper matrix-assisted laser desorption ionization-time of flight mass spectrometry was able to identify the C. laurentii isolates with an expanded custom database.


Assuntos
Criptococose/diagnóstico , Cryptococcus/classificação , Cryptococcus/isolamento & purificação , Erros de Diagnóstico , Técnicas de Tipagem Micológica/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , China , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Humanos , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA
18.
J Clin Microbiol ; 54(11): 2676-2680, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27535688

RESUMO

Candida haemulonii complex (Candida haemulonii, Candida haemulonii var. vulnera, and Candida duobushaemulonii) consists of emerging pathogens. Thirty-one isolates from 14 hospitals in China were studied for their species classification and antifungal susceptibilities. Performances of molecular (i.e., ribosomal DNA [rDNA] internal transcribed spacer [ITS] sequencing, D1/D2 sequencing, and ITS sequencer-based capillary gel electrophoresis [SCGE]) and phenotypic identification methods in species identification were compared. Twenty-six (83.9%) of 31 isolates were identified as C. haemulonii and 5 isolates were identified as C. duobushaemulonii by ITS sequencing as the reference method; results obtained by D1/D2 sequencing and ITS SCGE were concordant with those obtained by ITS sequencing for all (100%) of the isolates. All 31 isolates were identified as C. haemulonii by the Vitek matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) system (bioMérieux, France), whereas the Bruker MS system (Bruker Daltoniks, Germany) correctly provided species identification for 77.4% and 100% of isolates using cutoff scores for species of ≥2.0 and ≥1.70, respectively. The Vitek 2 compact (bioMérieux) only identified 9 (29%) of 31 isolates. All isolates showed high MICs for amphotericin B (range, 2 to >8 µg/ml) and fluconazole (≥128 µg/ml) but low MICs (≤0.5 µg/ml) for the echinocandins. Our results reinforce the need for MALDI-TOF MS and/or molecular differentiation of species within the C. haemulonii complex. The multiresistant antifungal susceptibility profile of these isolates represents a challenge to therapy.


Assuntos
Antifúngicos/farmacologia , Técnicas de Diagnóstico Molecular/métodos , Micoses/epidemiologia , Micoses/microbiologia , Saccharomycetales/efeitos dos fármacos , Saccharomycetales/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , China/epidemiologia , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Hospitais , Testes de Sensibilidade Microbiana
19.
J Clin Microbiol ; 54(5): 1376-80, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26912761

RESUMO

Among the 2,683 yeast isolates representing 41 different species (25 Candida and Candida-related species and 16 non-Candida yeast species) collected in the National China Hospital Invasive Fungal Surveillance Net (CHIF-NET) program (2012 to 2013), the Bruker Biotyper MS matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) system exhibited significantly higher accuracy rates than the Vitek MS system for identification of all yeast isolates (98.8% versus 95.4%, P <0.001 by Pearson's chi-square test) and for all Candida and Candida-related species isolates (99.4% versus 95.5%, P < 0.001).


Assuntos
Infecções Fúngicas Invasivas/diagnóstico , Infecções Fúngicas Invasivas/microbiologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Leveduras/classificação , Leveduras/isolamento & purificação , China , Monitoramento Epidemiológico , Humanos , Leveduras/química
20.
BMC Infect Dis ; 16(1): 557, 2016 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-27729031

RESUMO

BACKGROUND: Mycoplasma hominis, a well known cause of neonatal infection, has been reported as a pathogen in urogenital infections in adults; however, central nervous system (CNS) infections are rare. We report here the first case of M. hominis meningitis in China, post neurosurgical treatment for an intracerebral haemorrhage in a 71-year-old male. CASE PRESENTATION: We describe a 71-year-old man who developed M. hominis meningitis after neurosurgical treatment and was successfully treated with combined azithromycin and minocycline therapy of 2 weeks duration, despite delayed treatment because the Gram stain of cerebrospinal fluid (CSF) yielded no visible organisms. The diagnosis required 16S rDNA sequencing analysis of the cultured isolate from CSF. Literature review of M. hominis CNS infections yielded 19 cases (13 instances of brain abscess, 3 of meningitis, 1 spinal cord abscess and 1 subdural empyema each). Delay in diagnosis and initial treatment failure was evident in all cases. With appropriate microbiological testing, antibiotic therapy (ranging from 5 days to 12 weeks) and often, multiple surgical interventions, almost all the patients improved immediately. CONCLUSIONS: Both our patient findings and the literature review, highlighted the pathogenic potential of M. hominis together with the challenges prompted by rare infectious diseases in particular for developing countries laboratories with limited diagnostic resources.


Assuntos
Meningites Bacterianas/diagnóstico por imagem , Infecções por Mycoplasma/diagnóstico por imagem , Idoso , Antibacterianos/uso terapêutico , Povo Asiático , Humanos , Masculino , Meningites Bacterianas/tratamento farmacológico , Meningites Bacterianas/microbiologia , Infecções por Mycoplasma/tratamento farmacológico , Infecções por Mycoplasma/microbiologia , Mycoplasma hominis/isolamento & purificação , Falha de Tratamento
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