Identification Of Candida Glabrata Research Articles

The isolation and identification of Candida glabrata from avian species and a study of the antibacterial activities of Chinese herbal medicine in vitro

Previously, a fungus was isolated from a diseased pigeon group clinically suspected of being infected with Candida. The fungus was subsequently identified as Candida glabrata using morphology, physiology, biochemistry, and molecular biology testing methods. In the present study, to determine the controlling effects of Chinese herbal medicine for C. glabrata, the bacteriostatic effects of the ethanol extracts Acorus gramineus, Sophora flavescens, Polygonum hydropiper, Cassia obtusifolia, Pulsatilla chinensis, Dandelion, and Cortex phellodendri on C. glabrata in vitro were analyzed. The results showed that the minimum inhibitory concentrations (MIC80) of Cortex phellodendri was 0.25 μg/μL. Meanwhile, that of S. flavescens was 32 μg/μL; C. obtusifolia was 56 μg/μL; A. gramineus and Polygonum hydropiper was 64 μg/μL; and P. chinensis was 112 μg/μL. However, MIC80 for Dandelion was undetectable. In addition, improved drug sensitivity tests revealed that colonies had grown after 24 h in the blank group, as well as the Polygonum hydropiper, P. chinensis, Dandelion, and ethanol groups. The colonies first appeared at the 48-hour point in the other drug-sensitive medium of Chinese herbal medicine. However, no colony growth was found in Cortex phellodendri medium, and the formation of the maximum colony diameter in that group was later than the blank group (e.g., 96 h in the blank group and 120 h in the Chinese herbal medicine group). It was observed that only 17 colony-forming units had grown in 125 μg/μL of the S. flavescens medium, which was significantly different from other groups. Also, the final colony diameter was significantly smaller than that of the other experimental groups. Therefore, it was determined that the A. gramineus, S. flavescens, Polygonum hydropiper, Cassia obtusifolia, P. chinensis, and Cortex phellodendri had certain inhibitory effects on the growth of the C. glabrata. Among those, it was observed that the Cortex phellodendri had the strongest inhibitory effects, followed by the S. flavescens. In the future, these Chinese herbal medicines are expected to be used to treat the fungal infections related to C. glabrata in poultry to improve production performance.

Carbon-Electrode Dielectrophoresis to Identify Candida strains

Presented here is the use of 3D carbon microelectrodes in the separation of two different Candida strains using dielectrophoresis. The identification of Candida glabrata from Candida albicans has clinical relevance as front line antibiotics commonly used for Candida albicans, the most likely cause of candidiasis, are not effective to eradicate C. glabrata. Candidiasis occurs when a Candida species infiltrates the bloodstream. It is the most common bloodstream infection in the United States, and represents a significant challenge to the healthcare industry (1). While these yeast species are common inhabitants of the gastrointestinal tract and skin, they have the potential to cause infection in patients with compromised immune systems. These infections are problematic in hospitals, and have been estimated to have a mortality rate of up to 44% in some studies (2). Standard procedures following suspicion of candidiasis is the culturing of a sample for up to 1-2 days in agar followed by further testing to analyze spore formation before the species can be appropriately identified and treated (1). In the meantime, the patient is treated with a cocktail of antibiotics to target the most common pathogens. However, C. glabrata are resistant to commonly used antifungal drugs such as fluconazole (3). Hence, a rapid assay to detect the presence of Candida in a sample and further identifying the strain present can have a drastic impact on the treatment of candidiasis. This will enable timely treatment with the most suitable antibiotic, i.e. amphotericin B for C. glabrata, rather than treating the patient with a cocktail of antibiotics; an approach now leading to resistance in many Candida strains (3). Here we report the potential of dielectrophoresis to separate strains of Candida. Dielectrophoresis is an electrokinetic method that allows the dielectric properties of cells to be exploited for manipulation, isolation, and separation purposes. This is because targeted cells will display a specific response to a non-uniform electric field varying in frequency and magnitude (4). In our system, we implement the electric field gradient required for DEP using 3D carbon electrodes. When compared to traditional 2D electrodes, the use of 3D electrodes reduces the main distance from any cell flowing in the channel to the nearest electrode, thus resulting in better trapping throughput and efficiency (4). The use of carbon allows for a more robust device since carbon features a wider electrochemical stability than Au and Pt. Initial results show that different Candida strains feature a different DEP response at different frequencies (fig. 1). Using these methods of manipulation, our goal is to use this technique to devise a tool that uses the different response frequencies to separate the strains of Candida present in a sample. This could be useful in a clinical diagnostic setting for determining which strain is present to pinpoint certain interventions that are preferred for the different strains. Ongoing work is on determining the specific frequency at which one strain, and not the other, shows positive DEP as the basis of isolation. We will trap one strain on the electrode array while eluting the other one. This will allow for cell separation but also enrichment of the targeted species. Once enriched, the population concentration could be determined using optical or electrochemical means. Candidiasis affects thousands of people worldwide due to it’s resistant tendencies. A DEP-based assay to detect the cause of candidiasis will be an important tool in reducing its socioeconomic burden. Morrell M, Fraser VJ, Kollef MH. 2005. Delaying the empiric treatment of Candida bloodstream infection until positive blood culture results are obtained: a potential risk factor for hospital mortality. Antimicrob Agents Chemother 49:3640-3645. Almirante B, Rodriguez D, Park BJ, Cuenca-Estrella M, Planes AM, Almela M, Mensa J, Sanchez F, Ayats J, Gimenez M, Saballs P, Fridkin SK, Morgan J, Rodriguez-Tudela JL, Warnock DW, Pahissa A, Barcelona Candidemia Project Study Group. 2005. Epidemiology and predictors of mortality in cases of Candida bloodstream infection: results from population-based surveillance, Barcelona, Spain, from 2002 to 2003. J Clin Microbiol 43: 1829 –1835. https://doi.org/10.1128/JCM.43.4.1829-1835.2005Fidel PL, Jr, Vazquez JA, Sobel JD. 1999. Candida glabrata: review of epidemiology, pathogenesis, and clinical disease with comparison to C. albicans. Clin Microbiol Rev 12:80 –96.Martinez-Duarte, R., Renaud, P., & Madou, M. J. (2011). A novel approach to dielectrophoresis using carbon electrodes. Electrophoresis. doi:10.1002/elps.201100059 Figure 1

Molecular identification of Candida glabrata and C. parapsilosis based on sequencing analysis of rDNA

The taxonomy of the most Candida species especially C. parapsilosis and C. glabrata have undergone changes due to confuse in some taxonomic characters such as their color on CHROMagar and biochemical properties compare with accurate molecular method. The aim of this study was to evaluate the feasibility of using sequencing of the ribosomal internal transcribed spacer (ITS) region for identification of 18 Candida isolates. Preliminary CHROMagar assay and amplified ITS regions by primer pair ITS1/ITS4 and sequenced . Species identification performed based on the results of sequences which comparison by BLAST searches for homologous sequences in public databases. The CHROMagar assay results showed confuse in colonies colors of both species revealed white-pink color for both species .The results of PCR assay , rDNA sequences analysis and phylogenetic analyses showed accurate methods for identification of both species, Significant variation was observed among PCR products for 23 Candida species :511bp for C.parapsilosis 720 bp for C.kyfer and 780bp for C.glabrata .Sequence analysis show variation between C.glabrata, and C.parapsilosis and phylogenetic analyses produced different trees relative to analyses with consensus sequences. In conclusion, the CHROMagar candida medium unreliable test, showed high similarity in their color (white –pink color )characters for both C. parapsilosis and C. glabrata ,while the results of ITS sequencing provides a very accurate and useful method for the identification of Candida species in general trend , and C. parapsilosis and C. glabrata were showed distinct species based on sequences of ITS (rDNA).

Comparison of a New Commercial Test, GLABRATA RTT, with a Dipstick Test for Rapid Identification of Candida glabrata

This study compares the performance of a 3-h dipstick trehalose test with GLABRATA RTT, a new commercially available 20-min test for the rapid identification of Candida glabrata. With the exception of blood agar, GLABRATA RTT gave reliable results with all media tested and was always superior to the dipstick test.

Contribution of Various Techniques of Molecular Analysis to Strain Identification of Candida glabrata

Contribution of Various Techniques of Molecular Analysis to Strain Identification of Candida glabrata