Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “CANDIDA”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 289 records · Page 16Linked to original sources
PubMed1980

Adherence of Candida albicans and other Candida species to mucosal epithelial cells.

To study the possible involvement of candidal adherence in mucosal colonization, we examined the in vitro adherence capabilities of seven Candida species. Adherence was evaluated by direct microscopic examination and by a quantitative radiometric adherence test. The results indicate that C. albicans adheres to vaginal and buccal epithelial cells to a significantly greater degree (P less than 0.01) than the other species tested. C. tropicalis and C. stellatoidea demonstrated moderate adherence capabilities, while C. parapsilosis adhered only to a slight degree. Other species failed to interact with isolated mucosal cells. These findings suggest that there is a relationship between the adherence capabilities of the Candida species and their abilities to colonize mucosal surfaces, since those species which adhere are those which most frequently colonize mucosal surfaces. C. albicans was found to be adherent under a variety of environmental conditions. Stationary-phase blastospores of C. albicans were found to be more adherent than logarithmic-phase yeasts, and larger blastospore cell-to-epithelial cell ratios resulted in greater adherence values. The actual number of adherent yeasts varied considerably when epithelial cells were obtained from different donors.

Adhesiveness↗
PubMed1980

Pathogenicity of Candida tropicalis and Candida albicans after gastrointestinal inoculation in mice.

The ability of clinical isolates of Candida albicans and candida tropicalis to invade through normal and damaged gastrointestinal mucosa was determined. Adult mice were treated with either gentamicin or gentamicin and cytarabine. Suspensions of yeast cells (10(7)) were administered through a catheter intraesophageally. Invasion was determined by culturing liver, kidney, and lung tissue from mice sacrificed after 48 h. C. albicans and C. tropicalis were incapable of invading through normal gastrointestinal mucosa in mice treated only with gentamicin. Two isolates of C. tropicalis penetrated the damaged gastrointestinal mucosa in 69% (49 of 71) of mice treated with gentamicin and cytarabine. In contrast, three isolates of C. albicans penetrated he damaged gastrointestinal mucosa in only 23% (14 of 62) of mice. These results suggest that C. tropicalis is more capable of invading through damaged gastrointestinal mucosa than C. albicans. The observations in this mouse model parallel those seen in patients on cytotoxic drugs. Therefore, this model offers a tool for investigation of the pathogenicity of these organisms in a model analogous to the compromised host.

Animals↗
PubMed1985

Hydrophobic interaction in Candida albicans and Candida tropicalis adherence to various denture base resin materials.

The effects of hydrophobicities of substrate surfaces on microbial adherence were examined by using Candida albicans and Candida tropicalis and 21 denture base resin materials. With increasing surface free energy of resin plates, increasing adherence of C. albicans and decreasing adherence of C. tropicalis were observed. The surface free energy of C. albicans is higher than that of all resin material surfaces, and C. tropicalis has surface free energy lower than that of all materials used. In calculation of the changes of free energy accompanying the adherence, the higher adherence tendency was accompanied by a lower value for the free energy change in both species. From a different standpoint, the closer the surface free energy of the substrate surface and the microorganism, the higher was the probability of adherence.

Candida↗
PubMed1986

Influence of growth conditions on cell surface hydrophobicity of Candida albicans and Candida glabrata.

The effect of cultural conditions on cell surface hydrophobicity of Candida albicans and Candida glabrata was tested. C. albicans cells grown at room temperature were more hydrophobic than cells grown at 37 degrees C. No consistent pattern was observed with C. glabrata. Relative hydrophobicity was found to vary with the growth phase and growth medium for both species. The implications for pathogenesis studies are discussed.

Candida↗
PubMed1993

Experimental hematogenous candidiasis caused by Candida krusei and Candida albicans: species differences in pathogenicity.

Hematogenous infections caused by Candida krusei have been noted with increasing frequency, particularly in cancer patients receiving prophylaxis with antifungal triazoles. Progress in understanding the pathogenesis of this emerging infection has been limited by the lack of an animal model. We developed a CF1 mouse intravenous inoculation model of candidiasis to evaluate the pathogenicity of C. krusei in normal and immunosuppressed mice and to compare it with that of Candida albicans. Several inocula (10(6) to 10(8) CFU per animal) of two clinical strains of C. krusei and three American Type Culture Collection strains of C. albicans were tested. Groups of 20 mice each were injected with a single intravenous dose of one inoculum. Animals randomized to receive C. krusei were immunosuppressed by intraperitoneal injection of cyclophosphamide or the combination of cyclophosphamide plus cortisone acetate or they did not receive immunosuppressive agents (normal mice). One hundred percent mortality was observed in normal mice injected with 10(6) CFU of C. albicans per mouse compared with no mortality in normal mice that received 10(8) CFU of C. krusei per mouse (P < 0.01). Resistance to C. krusei infection was markedly lowered by immunosuppression, particularly by the combination of cyclophosphamide plus cortisone acetate, with a significantly shorter survival and a higher organ fungal burden in immunosuppressed than in normal animals (P < 0.01). Tissue infection was documented by culture and histopathologic findings in all examined organs.

Animals↗
PubMed1998

Simple, inexpensive, reliable method for differentiation of Candida dubliniensis from Candida albicans.

Candida dubliniensis is a recently described pathogenic species which shares many phenotypic features with Candida albicans, including the ability to form germ tubes and chlamydospores. These similarities have caused significant problems in the identification of C. dubliniensis by the average clinical mycology laboratory. To facilitate the differentiation of these species, we investigated the growth of 120 isolates of C. dubliniensis and 98 C. albicans isolates at 42 and 45 degrees C on Emmons' modified Sabouraud glucose agar (SGA) and 10 isolates of each species in yeast-peptone-dextrose broth. None of the C. dubliniensis isolates grew on the agar or in the broth medium at 45 degrees C, while 11 isolates were capable of growing on SGA at 42 degrees C. In contrast, all of the C. albicans isolates but one grew at 45 degrees C on or in either medium. These reproducible results clearly demonstrate that the incubation of isolates suspected to be C. dubliniensis or C. albicans at 45 degrees C provides a simple, reliable, and inexpensive method for the differentiation of the two species.

Candida↗
PubMed1999

Rapid PCR test for discriminating between Candida albicans and Candida dubliniensis isolates using primers derived from the pH-regulated PHR1 and PHR2 genes of C. albicans.

The development of a satisfactory means to reliably distinguish between the two closely related species Candida albicans and Candida dubliniensis in the clinical mycology laboratory has proved difficult because these two species are phenotypically so similar. In this study, we have detected homologues of the pH-regulated C. albicans PHR1 and PHR2 genes in C. dubliniensis. Restriction fragment length polymorphism analysis suggests that there are significant sequence differences between the genes of the two species. In order to exploit this apparent difference, oligonucleotide primers based on the coding sequence of the C. albicans PHR1 structural gene were designed and used in PCR experiments. Use of these primers with C. albicans template DNA from 17 strains yielded a predicted 1.6-kb product, while C. dubliniensis template DNA from 19 strains yielded no product. We therefore propose that PCR using these primers is a rapid and reliable means of distinguishing the two germ tube- and chlamydospore-producing species C. albicans and C. dubliniensis.

Apoenzymes↗
PubMed2000

Differentiation between Candida dubliniensis and Candida albicans by fatty acid methyl ester analysis using gas-liquid chromatography.

Candida dubliniensis is often found in mixed culture with C. albicans, but its recognition is hampered as the color of its colonies in primary culture on CHROMagar Candida varies. Furthermore, definite identification of C. dubliniensis is difficult to achieve, time-consuming, and expensive. Therefore, a method to discriminate between these two closely related yeast species by fatty acid methyl ester (FAME) analysis using gas-liquid chromatography (Sherlock Microbial Identification System [MIS]; MIDI, Inc., Newark, Del.) was developed. Although the chromatograms of these two species revealed no obvious differences when applying FAME analysis, a new library (CADLIB) was successfully created using Sherlock Library Generation Software (MIDI). The amount and frequency of FAME was analyzed using library training files (n = 10 for each species), preferentially those comprising reference strains. For testing the performance of the CADLIB, clinical isolates genetically assigned to the respective species (C. albicans, n = 32; C. dubliniensis, n = 28) were chromatographically analyzed. For each isolate tested, MIS computed a similarity index (SI) indicating a hierarchy of possible strain fits. When using the newly created library CADLIB, the SIs for C. albicans and C. dubliniensis ranged from 0.11 to 0.96 and 0.53 to 0. 93 (for all but one), respectively. Only three isolates of C. albicans (9.4%) were misidentified as C. dubliniensis, whereas all isolates of C. dubliniensis were correctly identified. Resulting differentiation accuracy was 90.6% for C. albicans and 100% for C. dubliniensis. Cluster analysis and principal component analysis of the resulting FAME profiles showed two clearly distinguishable clusters matching up with two assigned species for the strains tested. Thus, the created library proved to be well suited to discriminate between these two species.

AIDS-Related Opportunistic Infections↗
PubMed2001

Differentiation of Candida albicans and Candida dubliniensis by fluorescent in situ hybridization with peptide nucleic acid probes.

The recent discovery of Candida dubliniensis as a separate species that traditionally has been identified as Candida albicans has led to the development of a variety of biochemical and molecular methods for the differentiation of these two pathogenic yeasts. rRNA sequences are well-established phylogenetic markers, and probes targeting species-specific rRNA sequences have been used in diagnostic assays for the detection and identification of microorganisms. Peptide nucleic acid (PNA) is a DNA mimic with improved hybridization characteristics, and the neutral backbone of PNA probes offers significant advantages in whole-cell in situ hybridization assays. In this study, we developed PNA probes targeting the rRNAs of C. albicans and C. dubliniensis and applied them to a fluorescence in situ hybridization method (PNA FISH) for differentiation between C. albicans and C. dubliniensis. Liquid cultures were smeared onto microscope slides, heat fixed, and then hybridized for 30 min. Unhybridized PNA probe was removed by washing, and smears were examined by fluorescence microscopy. Evaluation of the PNA FISH method using smears of 79 C. dubliniensis and 70 C. albicans strains showed 100% sensitivity and 100% specificity for both PNA probes. We concluded that PNA FISH is a powerful tool for the differentiation of C. albicans and C. dubliniensis.

Candida↗
PubMed2001

Typing of Candida albicans isolates by sequence analysis of the cytochrome b gene and differentiation from Candida stellatoidea.

Including type strains, mitochondrial cytochrome b genes of 32 strains of Candida albicans and 6 strains of Candida stellatoidea, presently treated as a synonym for C. albicans, were partially sequenced. Analysis of 396-bp nucleotide sequences of the strains under investigation divided C. albicans isolates into three types: type I, type II, and type III; however, strains of C. stellatoidea represented distinct type IV isolates. Deduced amino acid sequences of type I, type II, and type III were identical and differed from that of type IV by one amino acid. Genotypes (rDNA type) of the test strains were also checked. Cytochrome b typing did not correlate with genotyping, and different genotypes occurred for one cytochrome b type. This study shows that cytochrome b gene sequences are useful for analyzing the genetic relatedness of C. albicans isolates and effective for differentiating C. stellatoidea from C. albicans.

Amino Acid Sequence↗
PubMed2001

Serological differentiation of experimentally induced Candida dubliniensis and Candida albicans infections.

Using a rabbit model of systemic infection, we show that it is possible to differentiate infections caused by Candida dubliniensis and other Candida species by detecting the antibody response mounted by the infected animals. These results confirm our previous observation in a patient with C. dubliniensis candidemia and suggest that detection of C. dubliniensis-specific antibodies is useful in the diagnosis of invasive candidiasis caused by this yeast.

Animals↗
PubMed2003

Candida dubliniensis infections in a pediatric population: retrospective identification from clinical laboratory isolates of Candida albicans.

Candida dubliniensis is a recently described species that shares many phenotypic and morphological features with Candida albicans. The clinical significance of isolating C. dubliniensis from the pediatric population is not clear, as most clinical isolates have been recovered from the oral cavities or bloodstreams of adults infected with human immunodeficiency virus. In order to understand further the epidemiology of C. dubliniensis in our pediatric population, we identified C. dubliniensis isolates from clinical isolates previously identified in the laboratory as C. albicans and conducted a retrospective chart review of cases of C. dubliniensis infections. A total of 205 isolates from 183 patients were tested, and only 14 (6.8%) were identified as C. dubliniensis. In 5 of the 14 positive cultures, C. dubliniensis was the sole organism isolated (two respiratory tract specimens, one tongue specimen, one vaginal specimen, and one skin specimen). A case review showed that there were no adverse outcomes for any of the patients, and only one of the patients with cultures positive for C. dubliniensis was immunocompromised. In our pediatric population, the distinction of C. dubliniensis from C. albicans did not prove to have significant clinical relevance. Data from further investigations may help to define better the role of C. dubliniensis as a potential pathogen in children.

Adolescent↗
PubMed2004

Tobacco agar, a new medium for differentiating Candida dubliniensis from Candida albicans.

Isolates of Candida dubliniensis may be misidentified as Candida albicans in microbiological laboratories if only the germ tube and/or the chlamydospore test is used for identification to the species level. In this study, we have evaluated the efficacy of tobacco agar for the differentiation of C. dubliniensis from C. albicans. On this medium at 28 degrees C, all 30 C. dubliniensis isolates produced yellowish-brown colonies with hyphal fringes and abundant chlamydospores, whereas 54 C. albicans isolates formed smooth, white-to-cream-colored colonies with no chlamydospore production. This medium provides a simple tool for presumptive differentiation of C. dubliniensis from C. albicans.

Agar↗
PubMed1993

Distinct mechanisms of epithelial adhesion for Candida albicans and Candida tropicalis. Identification of the participating ligands and development of inhibitory peptides.

The yeast Candida albicans is the leading cause of disseminated fungal infection in neonates, immunocompromised hosts, diabetics, and postoperative patients; Candida tropicalis is the second most frequent isolate. Because the integrin analogue in C. albicans shares antigenic, structural, and functional homologies with the beta 2-integrin subunits alpha M and alpha X, we investigated the role of integrin analogues in epithelial adhesion of C. albicans and C. tropicalis. On flow cytometry with the monoclonal antibody (mAb) OKM1, surface fluorescence was highest for C. albicans and significantly reduced for C. tropicalis (P < 0.001). However, adhesion to the human epithelial cell line HeLa S3 did not differ for these two candidal species: specific adhesion was highest for C. albicans at 44.0 +/- 1.8%, and only slightly lower for C. tropicalis at 38.8 +/- 3.6% (P = NS). The disparity between expression of the integrin analogue and epithelial adhesion suggested distinct mechanisms for this process in C. albicans versus C. tropicalis. Preincubation of C. albicans with anti-alpha M mAbs, with purified iC3b (the RGD ligand for the integrin analogue), or with 9-15-mer RGD peptides from iC3b all inhibited epithelial adhesion significantly (P < 0.001-0.04). Purified fibronectin or fibronectin-RGD peptides failed to block C. albicans adhesion. In contrast, epithelial adhesion of C. tropicalis was significantly inhibited by purified fibronectin and its RGD peptides (P < or = 0.021), but not by iC3b nor the iC3b-RGD peptides. Both iC3b and fibronectin were identified on the surface of epithelial cells after growth in serum-free medium. A polyclonal antibody to C3 inhibited C. albicans adhesion while a control antibody to fibronectin was ineffective; the converse was true for C. tropicalis. These results indicate that the pathogenic yeasts C. albicans and C. tropicalis recognize distinct RGD ligands present at the surface of the epithelial cell and that these interactions can be differentially inhibited by defined RGD peptides containing appropriate flanking sequences.

Antibodies↗
PubMed2002

Karyotyping of Candida albicans and Candida glabrata isolates from recurrent vaginal infections by pulsed-field gel electrophoresis.

In the present study, 16 women with recurrent vulvovaginal candidiasis (RVVC) due to Candida albicans and Candida (Torulopsis) glabrata were followed for a period of 4 to 12 months, and 36 vaginal isolates were evaluated by pulsed-field gel electrophoresis (PFGE). Eleven women were infected by C. albicans and 5 by C. glabrata. Three electrophoretic karyotypes of C. albicans and 3 of C. glabrata were identified throughout the follow-up. All patients but one was infected with the same karyotype of C. albicans or C. glabrata during the follow-up period. Two different karyotypes of C. glabrata were identified in one patient in the course of 12 months. The results confirmed the diversity of the karyotypes of C. albicans and C. glabrata causing vulvovaginitis, and demonstrated the persistence of colonization with the same strain over different periods of time despite therapy (15/16 women).

Candida↗
PubMed2004

The efficiency of the benzothiazole APB, the echinocandin micafungin, and amphotericin B in fluconazole-resistant Candida albicans and Candida dubliniensis.

This study presents the efficiency of the experimental antifungal agents 6-amino-2-n-pentylthiobenzothiazole (APB) and the echinocandin micafungin, and amphotericin B against fluconazole-resistant Candida albicans and Candida dubliniensis (MIC95 for fluconazole > 64 mg/l). The benzothiazole APB was less active against C. albicans and C. dubliniensis (MIC80 = 8 - 32 mg/l, MIC95 = 16 - 64 mg/l) than amphotericin B, which was efficient in a concentration range from 0.125 to 2 mg/l. However, the efficiency of micafungin was very high with MIC80, and MIC100 < or = 0.031 mg/l.

Amphotericin B↗