Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 49
Filtrar
Más filtros













Intervalo de año de publicación
1.
Microorganisms ; 11(5)2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37317123

RESUMEN

Background: Candida parapsilosis is the most common non-albicans candida species that causes invasive candidiasis, but little is known about its impacts on the outcomes of pediatric patients. We aimed to characterize the clinical characteristics, risk factors and outcomes of C. parapsilosis bloodstream infections (BSIs) in children. Methods: All pediatric patients with Candida parapsilosis BSIs between 2005 and 2020 from a medical center in Taiwan were enrolled and analyzed. The antifungal susceptibility, clinical manifestations, management and outcomes were investigated. Cases of Candida parapsilosis BSIs were compared between patients with C. albicans BSIs and other Candida spp. BSIs. Results: During the study period, 95 episodes (26.0% of total cases) of Candida parapsilosis BSIs were identified and analyzed. No significant difference was found between pediatric patients with C. parapsilosis BSIs and those with C. albicans BSIs in terms of patients' demographics, most chronic comorbidities or risk factors. Pediatric patients with C. parapsilosis BSIs were significantly more likely to have previous azole exposure and be on total parenteral nutrition than those with C. albicans BSIs (17.9 vs. 7.6% and 76.8 vs. 63.7%, p = 0.015 and 0.029, respectively). The duration of C. parapsilosis candidemia was relatively longer, and therefore patients often required a longer duration of antifungal treatment when compared with those of C. albicans candidemia, although the candidemia-attributable mortality rates were comparable. Of the C. parapsilosis isolates, 93.7% were susceptible to all antifungal agents, and delayed appropriate antifungal treatment was an independent factor in treatment failure. Conclusions: Pediatric patients with C. parapsilosis BSIs were more likely to have previous azole exposure and be on total parenteral nutrition, and the clinical significances included a longer duration of candidemia and patients often required a longer duration of antifungal treatment.

2.
Sci Rep ; 12(1): 21023, 2022 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-36470924

RESUMEN

Odontogenic rhinosinusitis is a subtype of rhinosinusitis associated with dental infection or dental procedures and has special bacteriologic features. Previous research on the bacteriologic features of odontogenic rhinosinusitis has mainly used culture-dependent methods. The variation of microbiota between odontogenic and nonodontogenic rhinosinusitis as well as the interplay between the involved bacteria have not been explored. Therefore, we enrolled eight odontogenic rhinosinusitis cases and twenty nonodontogenic rhinosinusitis cases to analyze bacterial microbiota through 16S rRNA sequencing. Significant differences were revealed by the Shannon diversity index (Wilcoxon test p = 0.0003) and PERMANOVA test based on weighted UniFrac distance (Wilcoxon test p = 0.001) between odontogenic and nonodontogenic samples. Anaerobic bacteria such as Porphyromonas, Fusobacterium, and Prevotella were significantly dominant in the odontogenic rhinosinusitis group. Remarkably, a correlation between different bacteria was also revealed by Pearson's correlation. Staphylococcus was highly positively associated with Corynebacterium, whereas Fusobacterium was highly negatively correlated with Prophyromonas. According to our results, the microbiota in odontogenic rhinosinusitis, predominantly anaerobic bacteria, was significantly different from that in nonodontogenic rhinosinusitis, and the interplay between specific bacteria may a major cause of this subtype of rhinosinusitis.


Asunto(s)
Microbiota , Sinusitis , Humanos , Disbiosis/complicaciones , Disbiosis/microbiología , ARN Ribosómico 16S/genética , Bacterias Anaerobias/genética , Sinusitis/complicaciones , Sinusitis/microbiología , Bacterias/genética , Fusobacterium/genética
3.
J Fungi (Basel) ; 8(11)2022 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-36354922

RESUMEN

Background: Pediatricians face a therapeutic challenge when patients with Candida bloodstream infections (BSIs) simultaneously have positive bacterial culture. We aim to characterize the clinical characteristics of pediatric Candida BSIs complicated with mixed bacteremia and subsequent bacterial infections, risk factors and impacts on outcomes. Methods: All episodes of pediatric Candida BSIs between 2005 and 2020 from a medical center in Taiwan were reviewed. Mixed Candida/bacterial BSIs were defined as isolation of a bacterial pathogen from blood cultures obtained within 48 h before or after the onset of Candida BSI. The clinical features and impacts of mixed Candida/bacterial BSIs were investigated. Results: During the study period, 320 patients with a total of 365 episodes of Candida BSIs were identified and analyzed. Mixed Candida/bacterial BSIs were 35 episodes (9.6%). No significant difference was found between mixed Candida/bacterial BSIs and monomicrobial Candida BSIs in terms of patient demographics, Candida species distributions, most chronic comorbidities or risk factors. Patients with mixed Candida/bacterial BSIs were associated with a significantly higher risk of subsequent bacteremia (51.4% vs. 21.2%, p < 0.001) and a relatively higher candidemia-attributable mortality rate (37.2% vs. 22.4%, p = 0.061) than those with monomicrobial Candida BSIs. Mixed Candida/bacterial BSIs were not an independent risk factor of treatment failure or final mortality according to multivariate logistic regression analyses. Conclusions: The clinical significance of mixed Candida/bacterial BSIs in children included a longer duration of septic symptoms, significantly higher likelihood to have subsequent bacteremia, and relatively higher risk of candidemia attributable mortality.

4.
J Fungi (Basel) ; 8(3)2022 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-35330235

RESUMEN

We have previously identified Candida albicans GPH1 (orf19.7021) whose protein product was associated with C. albicans Cdc4. The GPH1 gene is a putative glycogen phosphorylase because its Saccharomyces cerevisiae homolog participates in glycogen catabolism, which involves the synthesis of ß-glucan of the fungal cell wall. We made a strain whose CaCDC4 expression is repressed, and GPH1 is constitutively expressed. We established a GPH1 null mutant strain and used it to conduct the in vitro virulence assays that detect cell wall function. The in vitro virulence assay is centered on biofilm formation in which analytic procedures are implemented to evaluate cell surface hydrophobicity; competence, either in stress resistance, germ tube formation, or fibronection association; and the XTT-based adhesion and biofilm formation. We showed that the constitutively expressed GPH1 partially suppresses filamentation when the CaCDC4 expression is repressed. The C. albicans Gph1 protein is reduced in the presence of CaCdc4 in comparison with the absence of CaCdc4. Compared with the wild-type strain, the gph1Δ/gph1Δ mutant displayed a reduction in the capability to form germ tubes and the cell surface hydrophobicity but an increase in binding with fibronectin. Compared with the wild-type strain, the gph1Δ/gph1Δ mutant showed a rise in adhesion, the initial stage of biofilm formation, but displayed a similar capacity to form a mature biofilm. There was no major impact on the gph1Δ/gph1Δ mutant regarding the conditions of cell wall damaging and TOR pathway-associated nutrient depletion. We conclude that GPH1, adversely regulated by the filament suppressor CDC4, contributes to cell wall function in C. albicans.

5.
J Fungi (Basel) ; 7(12)2021 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-34947081

RESUMEN

Coinfection with Candida and Staphylococcus results in higher mortality in animal studies. However, the pathogenesis and interplay between C. albicans and S. aureus in bloodstream infections (BSIs) is unclear. This study determines the clinical features and outcomes of mixed C. albicans/S. aureus (CA/SA) BSIs and biofilm formation on pathogenesis during coinfection. Demographics and outcomes for mixed BSIs and monomicrobial candidemia were compared. Compared to 115 monomicrobial C. albicans BSIs, 22 patients with mixed CA/SA BSIs exhibited a significantly higher mortality rate and shorter survival time. In vitro and in vivo biofilm analysis showed that C. albicans accounted for the main biofilm architecture, and S. aureus increased its amount. Antibiotic tolerance in S. aureus, which adhered to Candida hyphae observed by scanning electron microscope, was demonstrated by the presence of wild-type C. albicans co-biofilm. Upregulation in exotoxin genes of S. aureus was evidenced by quantitative RT-PCR when a co-biofilm was formed with C. albicans. Mixed CA/SA BSIs result in a higher mortality rate in patients and in vivo surrogate models experiments. This study demonstrates that the virulence enhancement of C. albicans and S. aureus during co-biofilm formation contributes to the high mortality rate.

6.
Microorganisms ; 9(1)2021 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-33435490

RESUMEN

Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a rapid and accurate method to identify microorganisms in clinical laboratories. This study isolates yeast-like microorganisms in the oral washes that are collected from non-bedridden nursing home residents, using CHROMagar Candida plates, and identifies them using Bruker MALDI-TOF MS. The ribosomal DNA sequences of the isolates are then examined. Three hundred and twenty yeast isolates are isolated from the oral washes. Candida species form the majority (78.1%), followed by Trichosporon/Cutaneotrichosporon species (8.8%). Bruker MALDI-TOF MS gives a high-level confidence, with a log(score) value of ≥1.8, and identifies 96.9% of the isolates. There are six inconclusive results (1.9%), and those sequences are verified as rare clinical species, including Candida ethanolica, Cutaneotrichosporon jirovecii, Exophiala dermatitidis, and Fereydounia khargensis. Almost all of the isolates have a regular color on the CHROMagar Candida plates. If the colonies are grouped by color on the plates, a specific dominant yeast species is present in each color group, except for purple or orange isolates. In conclusion, MALDI-TOF MS is verified as a fast, accurate and practical method to analyze oral yeasts in elderly subjects.

7.
Med Mycol ; 59(5): 498-504, 2021 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-33099643

RESUMEN

Candida albicans bloodstream infection (BSI) is epidemiologically important because of its increasing frequency and serious outcome. Strain typing and delineation of the species are essential for understanding the phylogenetic relationship and clinical significance. Microsatellite CAI genotyping and multilocus sequence typing (MLST) were performed on 285 C. albicans bloodstream isolates from patients in Chang Gung Memorial Hospital at Linkou (CGMHL), Taiwan from 2003 to 2011. Data regarding demographics, comorbidities, risk factors, and clinical outcomes were recorded within adult patients with C. albicans BSI. Both CAI genotyping and MLST yielded comparable discriminatory power for C. albicans characterization. Besides, the distribution of CAI repetition showed a satisfactory phylogenetic association, which could be a good alternative method in the molecular phylogenetics of C. albicans and epidemiological studies. As for the clinical scenario, clade 17 isolates with CAI alleles either possessing 29 or more repetitions were related to higher 14-day and 30-day mortality, and shorter median survival days.


Asunto(s)
Candida albicans/genética , Candidiasis/microbiología , Repeticiones de Microsatélite , Anciano , Anciano de 80 o más Años , Alelos , Candida albicans/aislamiento & purificación , Candidiasis/epidemiología , Análisis por Conglomerados , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Tipificación de Secuencias Multilocus , Técnicas de Tipificación Micológica , Filogenia , Factores de Riesgo , Sepsis/microbiología , Taiwán/epidemiología
8.
Int J Biol Macromol ; 143: 724-731, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31734360

RESUMEN

Herein, positively surface-charged silver nanoparticles (AgNPs) capped with trimethylchitosan nitrate (TMCN) were synthesized using an environmentally friendly method. Nano-sized TMCN-AgNPs (~80 nm) with high zeta potential (>30 mV) provide sufficient static repulsion to stabilize colloid AgNPs in aqueous solutions without aggregation for >3 months. In in vitro cell cycle assays, TMCN-AgNPs showed low cytotoxicity towards L929 cells. A microdilution inhibition assay demonstrated the antifungal potential of TMCN-AgNPs, with a minimum inhibitory concentration of 0.06 mM against Candida tropicalis ATCC 750, and 0.46 mM against both Candida albicans ATCC 76615 and Candida glabrata ATCC 15545. Moreover, the addition of TMCN-AgNPs at 0.23 mM significantly reduced biofilm formation in 96-well plates with C. albicans and C. tropicalis. Importantly, when zebrafish eggs were infected with Candida cells, 0.23 mM TMCN-AgNPs greatly diminished the amount of biofilm on eggs and rescued the survival of embryos by up to 70%.


Asunto(s)
Antifúngicos/farmacología , Biopelículas/efectos de los fármacos , Candida/efectos de los fármacos , Quitosano/farmacología , Embrión no Mamífero/microbiología , Nanopartículas del Metal/química , Plata/farmacología , Pez Cebra/microbiología , Animales , Muerte Celular/efectos de los fármacos , Línea Celular , Embrión no Mamífero/efectos de los fármacos , Nanopartículas del Metal/ultraestructura , Ratones , Pruebas de Sensibilidad Microbiana , Óvulo/efectos de los fármacos , Pez Cebra/embriología
9.
J Clin Med ; 8(11)2019 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-31739506

RESUMEN

Fungal rhinosinusitis is a unique phenotype of chronic rhinosinusitis with unique clinical and histological characteristics. The role of bacterial microbiota in various phenotypes chronic rhinosinusitis is not thoroughly understood. Therefore, we conducted 16s rRNA amplification sequencing to determine differences in bacterial communities between phenotypes (fungal vs. non- fungal) and anatomical sites (middle meatus vs. nasopharynx). Endoscope-guided swabs were used to collect samples from the middle meatus and nasopharynx of seven consecutive patients with fungal and 18 consecutive patients with non-fungal rhinosinusitis. DNA was extracted and investigated through 16S rRNA amplification. Among samples from the middle meatus, Shannon diversity was significantly lower in those from the fungal rhinosinusitis group (p = 0.029). However, no significant differences in diversity were noted between nasopharynx samples (p = 0.85). Fungal rhinosinusitis samples exhibited a distinct distribution of taxon relative abundance, which involved not only the absence of rhinosinusitis-associated commensal Corynebacterium and Fusobacterium in the middle meatus but also a significant increase in Haemophilus prevalence and abundance. This is the first study to compare bacterial communities in fungal and non-fungal rhinosinusitis samples. Our findings demonstrated that bacterial community dysbiosis was more apparent in fungal rhinosinusitis samples and was limited to the middle meatus.

10.
Artículo en Inglés | MEDLINE | ID: mdl-30961803

RESUMEN

Salmonella Typhimurium and S. Stanley are the most prevalent serogroup B serovars to infect humans in Taiwan. The aim was to determine possible factors to influence the prevalence between S. Typhimurium and S. Stanley. Genotypes were determined by pulsed field gel electrophoresis (PFGE) analysis and the intracellular survival, phagocytosis, reactive oxygen species (ROS) production of human monocyte THP-1 cell and tumor necrosis factor-α(TNF-α), interleukin-6 (IL-6), and IL-1ßexpression in peripheral blood CD14+ cells after infection were analyzed. 182 S. Stanley was clonal disseminated with main pulsotypes 2 from 2004 to 2007. Overall S. Typhimurium evolved more genotypes, while S. Stanley conserved in genotypes. Human blood CD14+ monocytes expressed TNF-α, IL-6 and IL-1ß differently among serovars and bacterial conditions (live vs. killed). Live S. Stanley and S. Typhimurium suppressed the TNF-α and IL-6 expression compared to killed bacteria. However, live S. Typhimurium stimulated more IL-1ß expression than the killed bacteria, but S. Stanley expressed similar IL-1ß levels in both conditions. Furthermore, S. Stanley and S. Typhimurium differed in intracellular survival in the THP-1 cells, an early decrease for S. Stanley, not for S. Typhimurium. Additionally, higher reactive oxygen species (ROS) production in THP-1 cells was found agsinst S. Stanley infection, not found in S. Typhimurium. However, some isolates of S. Stanley could recover from early loss to become more in the monocytes than S. Typhimurium. Difference in phagocytized number, intracellular survival, ROS production and IL-1ß expression may contribute to prevalence different between two serovars.


Asunto(s)
Monocitos/inmunología , Fagocitosis/inmunología , Infecciones por Salmonella/inmunología , Salmonella typhimurium/inmunología , beta-Lactamasas/genética , Línea Celular Tumoral , Electroforesis en Gel de Campo Pulsado , Humanos , Interleucina-1beta/biosíntesis , Interleucina-6/biosíntesis , Especies Reactivas de Oxígeno/metabolismo , Infecciones por Salmonella/epidemiología , Infecciones por Salmonella/microbiología , Salmonella typhimurium/genética , Salmonella typhimurium/aislamiento & purificación , Células THP-1 , Taiwán , Factor de Necrosis Tumoral alfa/biosíntesis
11.
J Vet Res ; 63(1): 79-86, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30989138

RESUMEN

INTRODUCTION: Laryngeal swab samples collected from three waterfowl slaughterhouses in central Taiwan were cultured and suspected isolates of Riemerella anatipestifer were identified by API 20NE and 16S rDNA PCR. MATERIAL AND METHODS: Serum agglutination was used for serotyping, and antimicrobial susceptibility was tested. RESULTS: Seventy-six R. anatipestifer isolates were detected, and the prevalences in the ducks and geese were 12.3% (46/375) and 8.0% (30/375), respectively. The positive isolation rates were 65.6% for all arriving waterfowl, 76.0% for birds in the holding area, 1.6% for defeathered carcasses, but zero for degummed carcasses. A PCR examination detected R. anatipestifer in the slaughtering area frequently. Serotype B was dominant in both duck (34.8%) and goose (46.7%) isolates, but the wide serotype distribution may very well impede vaccination development. All isolates were resistant to colistin, and 79.7% were resistant to more than three common antibiotics. CONCLUSION: The results proved that most ducks had encountered antibiotic-resistant R. anatipestifer in rearing, which suggests that the bacterium circulates in asymptomatic waterfowl. It is worth noting that most waterfowl farms were found to harbour R. anatipestifer, and contaminated slaughterhouses are a major risk factor in its spread. Effective prevention and containment measures should be established there to interrupt the transmission chain of R. anatipestifer.

12.
Med Mycol ; 56(8): 972-978, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29325080

RESUMEN

Based on multiple locus sequence typing, we previously found that DST659 and DST693 were dominant genotypes of Candida albicans among the bloodstream isolates at Chang-Gung Memorial Hospital at Linkou. Biofilm-forming activity, which is critical for C. albicans virulence, probably contributed to the dominance of antifungal sensitive isolates in hospital. Both in vitro membrane weighting and in vivo zebrafish egg infection assays were used to evaluate the biofilm-forming activity of DST659 and DST693 genotypes. Medical records of the patients infected by these two genotypes were retrospectively reviewed. High biofilm-forming activity of DST659 isolates was demonstrated in vitro and further proved with the zebrafish egg infection model, which showed a positive correlation between the biofilm-forming extent on chorion and the in vitro biofilm activity. Moreover, significantly less embryos survived when infected with DST659 isolates than those with DST693 (1.25% vs. 11.43%), and the high-biofilm subset of DST659 showed a greater reduction in survival of embryos at 48 h post-infection than the low-biofilm subset (0 vs. 1.92%). Patients infected with DST659 seemed to survive slightly worse than those infected with DST693, although the difference was insignificant. It is noteworthy that DST659-infected patients were associated with a higher incidence in renal insufficiency as compared to those with DST693, the low biofilm genotype. We suggest that a strong biofilm activity of DST659 contributed to a high mortality rate in zebrafish hosts and poor renal function in patients, as well as gaining the dominance in the northern Taiwan.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Candida albicans/aislamiento & purificación , Candida albicans/fisiología , Candidemia/epidemiología , Candidemia/microbiología , Genotipo , Animales , Candida albicans/clasificación , Candida albicans/genética , Candidemia/mortalidad , Modelos Animales de Enfermedad , Femenino , Humanos , Incidencia , Masculino , Tipificación de Secuencias Multilocus , Estudios Retrospectivos , Análisis de Supervivencia , Taiwán/epidemiología , Virulencia , Pez Cebra/microbiología , Cigoto/microbiología
13.
Med Mycol ; 55(3): 314-322, 2017 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-27664170

RESUMEN

In the present data, we found that Candida albicans (C. albicans) caused bladder epithelial cell morphology alteration, cell damage, and inflammatory responses, including cyclooxygenase-2 (COX-2) gene and protein expression as well as prostaglandin E2 accumulation. In addition, the molecular pathway underlying C. albicans-induced urothelial COX-2 gene expression was examined. Among MAPK pathways, phosphorylation of ERK1/2, p38, and JNK each increased following C. albicans infection for 12 h. However, C. albicans-induced COX-2 protein expression was inhibited by specific inhibitors of ERK and p38 (U0126 and SB203580) but not by JNK inhibitor SP600125. Additional evidence came from the increased amount of phosphorylated RSK that is the mutual downstream molecule of ERK1/2 and p38. Furthermore, phosphorylation of RSK protein was reduced by the ERK and p38 inhibitor, suggesting that the urothelial COX-2 gene was induced majorly though the ERK/p38-RSK pathway by C. albicans infection. We also found transcription factor CREB-1 showed increased binding to the COX-2 gene promoter by chromatin immunoprecipitation assay. Next, we used receptor inhibitors including Toll-like receptor (TLR)-Myd88 inhibitor ST2825, Dectin-Syk inhibitor Syk inhibitor, and epidermal growth factor receptor (EGFR) inhibitor PD168393 to identify which one was the main target associated with C. albicans binding. The results revealed that it was EGFR, recognized by C. albicans, that mostly mediated the ERK/p38-RSK pathway activation to induce COX-2 gene expression, but this was not the case for TLRs and Dectin receptors. In summary, these results demonstrated the EGFR-ERK/p38-RSK-CREB-1 pathway was involved significantly in the C. albicans-induced COX-2 expression in human urothelium.


Asunto(s)
Candida albicans/fisiología , Ciclooxigenasa 2/biosíntesis , Receptores ErbB/metabolismo , Interacciones Huésped-Patógeno , Sistema de Señalización de MAP Quinasas , Urotelio/patología , Línea Celular , Humanos , Urotelio/microbiología
15.
Biomed Res Int ; 2016: 3237586, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27446946

RESUMEN

Dermatophytosis, which is caused mainly by genera of Trichophyton, Epidermophyton, and Microsporum, is a frequent dermatological problem in tropical and subtropical countries. Investigations were carried out in this study to evaluate the antidermatophytic activity of the stems, leaves, and seeds of Croton tiglium, one of the traditional medicine plants indigenous to Asia. Ethanolic extracts of the stems, leaves, and seeds of C. tiglium were prepared by cold soak or heat reflux methods. The antidermatophytic activities of the extracts were evaluated by disc diffusion and microdilution susceptibility assays against Trichophyton mentagrophytes, T. rubrum, and Epidermophyton floccosum. The active components in the extracts were analyzed and identified by GC-MS. All ethanolic extracts of C. tiglium showed some antifungal activities against the three dermatophytes. The ethanolic stem extract had the greatest inhibitory activities against T. mentagrophytes and E. floccosum with MICs at 0.16 mg/mL and had a lower activity against T. rubrum (MIC: 0.31 mg/mL). Oleic acid and hexadecanoic acid were found to be the major constituents in the stem extract that demonstrated strong antidermatophytic activities. The ethanolic extracts of stem or seed of C. tiglium exhibit strong antidermatophytic activities and, thus, could be considered for application on treating skin fungal infections after appropriate processing.


Asunto(s)
Arthrodermataceae/efectos de los fármacos , Arthrodermataceae/fisiología , Supervivencia Celular/efectos de los fármacos , Croton/química , Etanol/química , Extractos Vegetales/administración & dosificación , Antifúngicos/administración & dosificación , Supervivencia Celular/fisiología , Fármacos Dermatológicos/administración & dosificación , Relación Dosis-Respuesta a Droga , Extracción Líquido-Líquido/métodos , Componentes Aéreos de las Plantas/química , Extractos Vegetales/síntesis química , Resultado del Tratamiento
16.
J Microbiol Immunol Infect ; 49(6): 892-901, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25592882

RESUMEN

BACKGROUND/PURPOSE: Escherichia coli is a common pathogen to cause clinical and subclinical mastitis in cows. A total of 57 E. coli isolates from raw milk from cows were characterized genetically and biochemically. METHODS: Extended-spectrum ß-lactamase (ESBL) genes, the mechanism for fluoroquinolone resistance, and variations in virulence genes and genomes of these E. coli isolates were investigated by the antimicrobial susceptibility test, simplex and multiplex polymerase chain reaction (PCR), and pulsed-field gel electrophoresis (PFGE). RESULTS: All E. coli isolates were resistant to cloxacillin (100%) and to a lesser extent (50%) to tetracycline, neomycin, gentamycin, ampicillin, ceftriaxone, cefotaxime (CTX), and ceftazidime (CAZ). Nearly 70% of the isolates were resistant to at least two antimicrobials and 28.1% carried AmpA and AmpC genes simultaneously. The predominant bla gene was blaTEM, followed by blaCMY, blaCTX, blaSHV, and blaDHA. Among the six (10.5%) ESBL-producing E. coli carrying blaCTX-M15, blaCTX-M55, or blaCTX-M14, two isolates 31 of ST410 in the ST23 complex and 58 of ST167 in the ST10 complex were also resistant to ciprofloxacin, enrofloxacin, and levofloxacin, with mutations at codon 83 from serine to leucine and codon 87 from aspartic acid to asparagine in GyrA and at codon 80 from serine to isoleucine in ParC. These isolates were genetically diverse in pulsotype analysis, lacked toxin genes of human pathogenic E. coli and carried mostly the prevalent virulence genes fimH, papGII, and α-hemolysin. CONCLUSION: Lacking virulence genes examined, genetic diverse E. coli isolates are unrelated to human pathogenic E. coli. Enhancing sanitation in milk processing and transportation is needed to eliminate multidrug-resistant (MDR), fluoroquinolone-resistant, and ESBL-producing E. coli isolates.


Asunto(s)
Antibacterianos/farmacología , Infecciones por Escherichia coli/veterinaria , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Fluoroquinolonas/farmacología , Mastitis Bovina/microbiología , Leche/microbiología , Resistencia betalactámica/genética , beta-Lactamasas/genética , Animales , Proteínas Bacterianas/genética , Bovinos , Cloxacilina/farmacología , Electroforesis en Gel de Campo Pulsado , Escherichia coli/efectos de los fármacos , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/microbiología , Femenino , Pruebas de Sensibilidad Microbiana , Reacción en Cadena de la Polimerasa Multiplex , Taiwán
17.
Med Mycol ; 53(8): 828-36, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26333357

RESUMEN

Candida albicans is a common cause of bloodstream fungal infections in hospitalized patients. To investigate its epidemiology, multilocus sequence typing (MLST) was performed on 285 C. albicans bloodstream isolates from patients in Chang Gung Memorial Hospital at Linkou (CGMHL), Taiwan from 2003 to 2011. Among these isolates, the three major diploid sequence types (DSTs) were 693, 659, and 443 with 19, 16, and 13 isolates, respectively. The 179 DSTs were classified into 16 clades by unweighted pair-group method using arithmetic averages (UPGMA). The major ones were clades 1, 4, 3, and 17 (54, 49, 31, and 31 isolates, respectively). Further analyses with eBURST clustered the 285 isolates into 28 clonal complexes (CC). The most common complexes were CC8, CC20, and CC9. DST 693 that had the highest number of isolates was determined to be the cluster founder of CC20, which belonged to clade 3. So far, 33 isolates worldwide including 29 from Taiwan and 4 from Korea, are CC20, suggesting that CC20 is an Asian cluster. Two fluconazole-resistant isolates belonging to CC12 and CC19 were detected. All other CGMHL isolates were susceptible to 5-flucytosine, amphotericin B, anidulfungin, caspofungin, fluconazole, itraconazole, micafungin, posaconazole, and voriconazole. However, CC20 isolates exhibited significantly lower susceptibility to fluconazole. In conclusion, the 285 CGMHL C. albicans isolates displayed geographically clustering with Asian isolates, and most of them are susceptible to common antifungal drugs. Isolates of DST 693, a Taiwanese major genotype belonging to MLST clade 3, were more resistant to fluconazole than other isolates.


Asunto(s)
Candida albicans/clasificación , Candida albicans/genética , Candidiasis Invasiva/epidemiología , Infección Hospitalaria/epidemiología , Tipificación de Secuencias Multilocus , Técnicas de Tipificación Micológica , Centros de Atención Terciaria , Adolescente , Adulto , Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Candida albicans/aislamiento & purificación , Candidiasis Invasiva/microbiología , Niño , Preescolar , Análisis por Conglomerados , Infección Hospitalaria/microbiología , Farmacorresistencia Fúngica , Genotipo , Humanos , Lactante , Pruebas de Sensibilidad Microbiana , Epidemiología Molecular , Taiwán/epidemiología
18.
Molecules ; 20(7): 11994-2015, 2015 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-26133763

RESUMEN

To examine the effect of hydrophobicity on the anticancer activity of 1,4-naphthoquinone derivatives, a series of compounds bearing a 2-O-alkyl-, 3-C-alkyl- or 2/3-N-morpholinoalkyl group were synthesized and evaluated for their anticancer activity against five human cancer cell lines in vitro. The cytotoxicity of these derivatives was assayed against HT-29, SW480, HepG2, MCF-7 and HL-60 cells by the MTT assay. Among them, 2-hydroxy-3-farnesyl-1,4-naphthoquinone (11a) was found to be the most cytotoxic against these cell lines. Our results showed that the effectiveness of compound 11a may be attributed to its suppression of the survival of HT-29. Secondly, in the Hoechst 33258 staining test, compound 11a-treated cells exhibited nuclear condensation typical of apoptosis. Additionally, cell cycle analysis by flow cytometry indicated that compound 11a arrested HT-29 cells in the S phase. Furthermore, cell death detected by Annexin V-FITC/propidium iodide staining showed that compound 11a efficiently induced apoptosis of HT-29 in a concentration-dependent manner. Taken together, compound 11a effectively inhibits colon cancer cell proliferation and may be a potent anticancer agent.


Asunto(s)
Lípidos/química , Naftoquinonas/síntesis química , Naftoquinonas/farmacología , Neoplasias/patología , Ciclo Celular , Línea Celular Tumoral , Citometría de Flujo , Humanos , Naftoquinonas/química
19.
Artículo en Inglés | MEDLINE | ID: mdl-26136773

RESUMEN

BACKGROUND: Cryptococcal meningitis is a deadly fungal infection. This study aimed to characterize the epidemiology of cerebral cryptococcosis and to define its prognostic factors. METHODS: This cross-sectional study collected clinical information from cryptococcal meningitis patients with confirmed cerebral cryptococcosis from 2006 to 2012 at the Changhua Christian Healthcare System to access prognostic factors. RESULTS: Fifty-nine adult cryptococcal meningitis patients were studied. The incidence at Changhua Christian Healthcare System was approximately 170 episodes per 100,000 patients within the studied period. Forty-one of 59 cryptococcal meningitis patients developed complications. Overall, 12 of 59 patients died, for a three-month mortality rate of 20.3 %. Prognostic factors positively associated with the three-month mortality included age (>55 years), patient delay, prolonged delay by the doctor in administering antifungal agent therapy, duration of intensive care unit stay, chronic lung disease, cryptococcemia, headache, altered mental status, positive blood cultures, and high cerebrospinal fluid opening pressure (≥250 mm H2O). CONCLUSIONS: We strongly recommend early administration of an antifungal agent to each suspected cryptococcal meningitis patient to decrease both the delay by doctors in administering therapy and the mortality risk. Aggressive and supportive care for severe cryptococcal meningitis patients is critical to decrease overall mortality from this infection.

20.
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-954763

RESUMEN

BackgroundCryptococcal meningitis is a deadly fungal infection. This study aimed to characterize the epidemiology of cerebral cryptococcosis and to define its prognostic factors.MethodsThis cross-sectional study collected clinical information from cryptococcal meningitis patients with confirmed cerebral cryptococcosis from 2006 to 2012 at the Changhua Christian Healthcare System to access prognostic factors.ResultsFifty-nine adult cryptococcal meningitis patients were studied. The incidence at Changhua Christian Healthcare System was approximately 170 episodes per 100,000 patients within the studied period. Forty-one of 59 cryptococcal meningitis patients developed complications. Overall, 12 of 59 patients died, for a three-month mortality rate of 20.3 %. Prognostic factors positively associated with the three-month mortality included age (>55 years), patient delay, prolonged delay by the doctor in administering antifungal agent therapy, duration of intensive care unit stay, chronic lung disease, cryptococcemia, headache, altered mental status, positive blood cultures, and high cerebrospinal fluid opening pressure (>250 mm H2O).ConclusionsWe strongly recommend early administration of an antifungal agent to each suspected cryptococcal meningitis patient to decrease both the delay by doctors in administering therapy and the mortality risk. Aggressive and supportive care for severe cryptococcal meningitis patients is critical to decrease overall mortality from this infection.(AU)


Asunto(s)
Pronóstico , Meningitis Criptocócica/epidemiología , Meningitis , Factores de Riesgo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA