共查询到20条相似文献,搜索用时 15 毫秒
1.
Yun-Liang Yang Yi-Hsuan Lin Ming-Yang Tsao Chia-Geun Chen Hsin-I Shih Jen-Chung Fan Jang-Shiun Wang Hsiu-Jung Lo 《BMC molecular biology》2006,7(1):22-6
Background
In the past decades, the prevalence of candidemia has increased significantly and drug resistance has also become a pressing problem. Overexpression of CDR1, an efflux pump, has been proposed as a major mechanism contributing to the drug resistance in Candida albicans. It has been demonstrated that biological fluids such as human serum can have profound effects on antifungal pharmacodynamics. The aim of this study is to understand the effects of serum in drug susceptibility via monitoring the activity of CDR1 promoter of C. albicans. 相似文献2.
Adnane Sellam Thamir Al-Niemi Kathleen McInnerney Susan Brumfield Andre Nantel Peter A Suci 《BMC microbiology》2009,9(1):25-22
Background
Dispersal from Candida albicans biofilms that colonize catheters is implicated as a primary factor in the link between contaminated catheters and life threatening blood stream infections (BSI). Appropriate in vitro C. albicans biofilm models are needed to probe factors that induce detachment events. 相似文献3.
Yu-Chao Wang Chung-Yu Lan Wen-Ping Hsieh Luis A Murillo Nina Agabian Bor-Sen Chen 《BMC bioinformatics》2010,11(1):53
Background
Candida albicans is a commonly encountered fungal pathogen in humans. The formation of biofilm is a major virulence factor in C. albicans pathogenesis and is related to antidrug resistance of this organism. Although many factors affecting biofilm have been analyzed, molecular mechanisms that regulate biofilm formation still await to be elucidated. 相似文献4.
Heleen Nailis Tom Coenye Filip Van Nieuwerburgh Dieter Deforce Hans J Nelis 《BMC molecular biology》2006,7(1):25-9
Background
Candida albicans biofilms are commonly found on indwelling medical devices. However, the molecular basis of biofilm formation and development is not completely understood. Expression analysis of genes potentially involved in these processes, such as the ALS (Agglutinine Like Sequence) gene family can be performed using quantitative PCR (qPCR). In the present study, we investigated the expression stability of eight housekeeping genes potentially useful as reference genes to study gene expression in Candida albicans (C. albicans) biofilms, using the geNorm Visual Basic Application (VBA) for Microsoft Excel. To validate our normalization strategies we determined differences in ALS1 and ALS3 expression levels between C. albicans biofilm cells and their planktonic counterparts. 相似文献5.
Adnane Sellam Hervé Hogues Christopher Askew Faiza Tebbji Marco van het Hoog Hugo Lavoie Carol A Kumamoto Malcolm Whiteway André Nantel 《Genome biology》2010,11(7):R71
Background
Compared to other model organisms and despite the clinical relevance of the pathogenic yeast Candida albicans, no comprehensive analysis has been done to provide experimental support of its in silico-based genome annotation. 相似文献6.
Background
To date very few incidences of interdomain gene transfer into fungi have been identified. Here, we used the emerging genome sequences of Candida albicans WO-1, Candida tropicalis, Candida parapsilosis, Clavispora lusitaniae, Pichia guilliermondii, and Lodderomyces elongisporus to identify recent interdomain HGT events. We refer to these as CTG species because they translate the CTG codon as serine rather than leucine, and share a recent common ancestor. 相似文献7.
Thaís Helena Gasparoto Narciso Almeida Vieira Vinicius Carvalho Porto Ana Paula Campanelli Vanessa Soares Lara 《Immunity & ageing : I & A》2009,6(1):3
Background
Ageing leads to a decline in the function of the immune system, increasing the body's susceptibility to infections through the impairment of T-cells, macrophages, neutrophils and dendritic cells Denture stomatitis is a primary oral disease affecting elderly denture wearers. The major etiologic factor involved in this pathology is the infection by Candida albicans, an opportunistic pathogen that causes local and disseminated diseases in immunosuppressed humans. Neutrophils play a critical role in the immune response against C. albicans and are continually present in the salivary fluid and in the blood. The aim of this study was to determine ageing-related changes in salivary and blood neutrophils and their potential implications in Candida-related denture stomatitis. 相似文献8.
Mingyue Wang Pranab K Mukherjee Jyotsna Chandra Ali Abdul Lattif Thomas S McCormick Mahmoud A Ghannoum 《BMC microbiology》2008,8(1):31
Background
We have previously shown that supernatant from Candida albicans (CA) culture contains a Secretory Interleukin (IL)-12 Inhibitory Factor (CA-SIIF), which inhibits IL-12 production by human monocytes. However, the effect of CA-SIIF on secretion of other cytokines by monocytes is unknown, and detailed characterization of this factor has not been performed. 相似文献9.
Background
Candida albicans SUR7 has been shown to be required for plasma membrane organization and cell wall synthesis, but its role in virulence is not known. Using a bioinformatics strategy, we previously identified several novel putative secretion pathway proteins potentially involved in virulence, including the C. albicans homolog of the Saccharomyces cerevisiae endocytosis-related protein Sur7p. We therefore generated a C. albicans sur7Δ null mutant and examined its contribution to key virulence attributes. 相似文献10.
Heleen Nailis Soňa Kucharíková Markéta Řičicová Patrick Van Dijck Dieter Deforce Hans Nelis Tom Coenye 《BMC microbiology》2010,10(1):114
Background
Candida albicans infections are often associated with biofilm formation. Previous work demonstrated that the expression of HWP1 (hyphal wall protein) and of genes belonging to the ALS (agglutinin-like sequence), SAP (secreted aspartyl protease), PLB (phospholipase B) and LIP (lipase) gene families is associated with biofilm growth on mucosal surfaces. We investigated using real-time PCR whether genes encoding potential virulence factors are also highly expressed in biofilms associated with abiotic surfaces. For this, C. albicans biofilms were grown on silicone in microtiter plates (MTP) or in the Centres for Disease Control (CDC) reactor, on polyurethane in an in vivo subcutaneous catheter rat (SCR) model, and on mucosal surfaces in the reconstituted human epithelium (RHE) model. 相似文献11.
Background
Candida albicans is a low level commensal organism in normal human populations with the continuous potential to expand and cause a spectrum of clinical conditions.Methodology/Principal Findings
Using ex vivo human organ cultures and populations of primary human cells, we have developed several related experimental systems to examine early-stage interactions between C. albicans and mucosal surfaces. Experiments have been conducted both with exogenously added C. albicans and with overtly normal human mucosal surfaces supporting pre-existing infections with natural isolates of Candida. Under different culture conditions, we have demonstrated the formation of C. albicans colonies on human target cells and filament formation, equivalent to tissue invasion.Conclusions/Significance
These organ culture systems provide a valuable new resource to examine the molecular and cellular basis for Candida colonization of human mucosal surfaces. 相似文献12.
Candida albicans biofilms on most medical devices are exposed to a flow of body fluids that provide water and nutrients to the fungal cells.
While C. albicans biofilms grown in vitro under static conditions have been exhaustively studied, the same is not true for biofilms developed
under continuous flow of replenishing nutrients. Here, we describe a simple flow biofilm (FB) model that can be built easily
with materials commonly available in most microbiological laboratories. We demonstrate that C. albicans biofilms formed using this flow system show increased architectural complexity compared to biofilms grown under static conditions.
C. albicans biofilms under continuous medium flow grow rapidly, and by 8 h show characteristics similar to 24 h statically grown biofilms.
Biomass measurements and microscopic observations further revealed that after 24 h of incubation, FB was more than twofold
thicker than biofilms grown under static conditions. Microscopic analyses revealed that the surface of these biofilms was
extremely compact and wrinkled, unlike the open hyphal layer typically seen in 24 h static biofilms. Results of antifungal
drug susceptibility tests showed that C. albicans cells in FB exhibited increased resistance to most clinically used antifungal agents. 相似文献
13.
Background
Elucidation of the communal behavior of microbes in mixed species biofilms may have a major impact on understanding infectious diseases and for the therapeutics. Although, the structure and the properties of monospecies biofilms and their role in disease have been extensively studied during the last decade, the interactions within mixed biofilms consisting of bacteria and fungi such as Candida spp. have not been illustrated in depth. Hence, the aim of this study was to evaluate the interspecies interactions of Pseudomonas aeruginosa and six different species of Candida comprising C. albicans, C. glabrata, C. krusei, C. tropicalis, C. parapsilosis, and C. dubliniensis in dual species biofilm development. 相似文献14.
Background
Reverse engineering of gene regulatory networks can be used to predict regulatory interactions of an organism faced with environmental changes, but can prove problematic, especially when focusing on complicated multi-factorial processes. Candida albicans is a major human fungal pathogen. During the infection process, this fungus is able to adapt to conditions of very low iron availability. Such adaptation is an important virulence attribute of virtually all pathogenic microbes. Understanding the regulation of iron acquisition genes will extend our knowledge of the complex regulatory changes during the infection process and might identify new potential drug targets. Thus, there is a need for efficient modelling approaches predicting key regulatory events of iron acquisition genes during the infection process. 相似文献15.
doi: 10.1111/j.1741‐2358.2011.00485.x Candida albicans biofilm formation on soft denture liners and efficacy of cleaning protocols Objective: The aim of this study was to investigate Candida albicans biofilm formation on denture liners and to analyse the efficacy of cleaning protocols. Material and methods: Specimens were prepared from four silicone‐based soft denture liners. After artificial ageing and surface free energy determination, specimens were incubated with saliva (2 h) and Candida albicans ATCC 10231 for either short‐ (2.5 h) or long‐term (24 h) biofilm formation. Adherent cells were determined either after incubation of specimens with Candida albicans or after treatment with different denture cleaning protocols. Statistical analysis was performed using one‐way anova and the Games–Howell test (α = 0.05). Results: For both short‐ and long‐term biofilm formation, similar amounts of Candida albicans cells were found on the surface of the different liners (p = 0.295 and 0.178, respectively). For both short‐ and long‐term biofilm formation, the highest cleaning efficacy was observed for sodium hypochlorite (NaOCl; p < 0.01). The efficacy of the chemical denture cleaner in removing long‐term Candida albicans biofilms was significantly lower than the efficacy of removal by brushing (p < 0.001). Conclusion: Different silicone‐based soft denture liners yield similar Candida albicans biofilm formation on their surface. The highest efficacy for the removal of Candida albicans biofilms was identified for NaOCl. Chemical denture cleaners appear to have rather low efficacy to remove mature Candida albicans biofilms. 相似文献
16.
Anaerobic biodegradation of phenol by <Emphasis Type="Italic">Candida albicans</Emphasis> PDY-07 in the presence of 4-chlorophenol 总被引:1,自引:0,他引:1
Guoying Wang Jianping Wen Guanghai Yu Hongmei Li 《World journal of microbiology & biotechnology》2008,24(11):2685-2691
Biodegradation of phenol and 4-chlorophenol (4-cp) using pure culture of Candida albicans PDY-07 under anaerobic condition was studied. The results showed that the strain could completely degrade up to 1,800 mg/l
phenol within 68 h. The capacity of the strain to degrade phenol was higher than that to degrade 4-cp. In the dual-substrate
system, 4-cp intensely inhibited phenol biodegradation. Comparatively, low-concentration phenol from 25 to 150 mg/l supplied
a carbon and energy source for Candida albicans PDY-07 in the early phase of biodegradation and accelerated the assimilation of 4-cp, which resulted in that 50 mg/l 4-cp
was degraded within less time than that without phenol. While the biodegradation of 50 mg/l 4-cp was inhibited in the presence
of 200 mg/l phenol. In addition, the intrinsic kinetics of cell growth and substrate degradation were investigated with phenol
and 4-cp as single and dual substrates in batch cultures. The results demonstrated that the models adequately described the
dynamic behaviors of biodegradation by Candida albicans PDY-07. 相似文献
17.
Esra Şeker 《Mycopathologia》2010,169(4):303-308
In this study, identification of 207 Candida isolates, previously isolated from mastitic bovine quarter milk samples at the level of genus, was made using API 20 C AUX
system. The most frequently isolated species were Candida krusei (34.8%), followed by Candida rugosa (16.4%), Candida kefyr (12.6%), Candida albicans (10.1%), and Candida tropicalis (9.2%). Less common isolates were Candida zeylanoides (5.8%), Candida parapsilosis (4.3%), Candida guilliermondii (3.4%), Candida famata (1.9%), and Candida glabrata (1.5%). Additionally, in vitro hemolytic activity of all Candida strains were also examined in the present study. C. krusei (72 isolates), C. kefyr (26), C. albicans (21), C. tropicalis (19), C. zeylanoides (12), and C. glabrata (3) demonstrated both alpha and beta hemolysis at 48-h postinoculation. Only alpha hemolysis was detected in C. rugosa (34), C. guilliermondii (7), and C. famata (4), while C. parapsilosis (9) did not show any hemolytic activity after incubation for 72 h. Statistically significant difference (P < 0.001) was determined between the beta-hemolytic activities of Candida strains. The hemolytic activities of C. zeylanoides, C. albicans and C. kefyr were higher than other strains. This is the first study to describe variable hemolysis types exhibited by different Candida strains isolated from bovine mastitic milk in Turkey. 相似文献
18.
CHROMagar has been reported to be useful for the rapid and accurate identification of Candida species. We tested 135 isolates of Candida species isolated from oropharyngeal candidiasis in HIV patients and found that it was useful in the presumptive identification
of Candida albicans and Candida krusei. Occasional strains of C. tropicalis produced colonies with a greenish tinge making it difficult to differentiate from C. albicans. 相似文献
19.
The aim of the present work was to observe microbial decolorization and biodegradation of the Direct Violet 51 azo dye by
Candida albicans isolated from industrial effluents and study the metabolites formed after degradation. C. albicans was used in the removal of the dye in order to further biosorption and biodegradation at different pH values in aqueous solutions.
A comparative study of biodegradation analysis was carried out using UV–vis and FTIR spectroscopy, which revealed significant
changes in peak positions when compared to the dye spectrum. Theses changes in dye structure appeared after 72 h at pH 2.50;
after 240 h at pH 4.50; and after 280 h at pH 6.50, indicating the different by-products formed during the biodegradation
process. Hence, the yeast C. albicans was able to remove the color substance, demonstrating a potential enzymatic capacity to modify the chemical structure of
pigments found in industrial effluents. 相似文献
20.