Cytokine gene polymorphism in denture stomatitis patients: A clinical study.

OBJECTIVE: This clinical study investigated the association between cytokine gene polymorphism and Candida growth in denture stomatitis (DS) patients. SUBJECTS AND METHODS: Saliva and blood samples of 160 complete denture wearers (80 healthy controls and 80 with DS) were collected for mycological and gene polymorphism testing, respectively. Salivary Candida growth and TNF-α, TGF-ß, IL-6, and IL-10 genotypes were investigated. Data were analyzed using Student's t test, Mann-Whitney U test, chi-square analysis, and continuity (yates) correction tests (p < .05). RESULTS: Candida albicans colony counts in saliva were significantly higher in the DS group and in the TNF-α GG genotype (p < .05). TGF-ß TC GG and TGF-ß CC GG haplotypes were significantly higher in DS and control groups, respectively (p < .05). C. albicans colony counts were significantly higher in control group in the TGF-ß TC GG haplotype (p < .05). Candida glabrata colony counts were significantly higher in the DS group than the control group in IL-6 GG genotype (p < .05). The difference between DS types in IL-6 genotypes was significant with lower expression level in DS type 3 than DS type 1 and also type 2 (p ≤ .01). CONCLUSION: The significant differences in some genotypes of the TNF-α, TGF-ß, and IL-6 in DS patients are promising in understanding the host defense in DS.

Typing of Pseudomonas aeruginosa strains in Turkish cystic fibrosis patients.

The majority of cystic fibrosis (CF) patients suffer from chronic respiratory infection with the opportunistic bacterial pathogen Pseudomonas aeruginosa. The virulence of P. aeruginosa is associated with the presence of various extracellular factors, like alginate, elastase, alkaline protease which contribute tissue destruction and assist bacterial invasion. Virulence factor production of P. aeruginosa strains isolated from 46 CF patients followed in two cities in Turkey was detected. Strains were compared genotypically by arbitrarily primed PCR. Antimicrobial susceptibilities to 12 antibiotics were determined by broth microdilution method. Evaluation of virulence factor results revealed that 95.8% of the strains were alginate, 71.7% elastase and 52.1% alkaline protease producers. AP-PCR analysis revealed 35 genotypes indicated almost a complete discrepancy among the strains. The most effective drugs were penems and quinolones. Among aminoglycosides amikacin was the most effective one and a high level resistance to beta lactams was observed. Alginate is the most important virulence factor in the chronic colonisation of CF patients with P. aeruginosa. No evidence for cross infection between patients and for relationship between phenotypes and genotypes of the strains was found.

Investigation of cross-resistance between rifampin and rifabutin in Mycobacterium tuberculosis complex strains.

In order to indicate the cross-resistance between rifampin (RMP) and rifabutin (RBU), minimal inhibitory concentrations (MICs) of RBU were investigated in 50 Mycobacterium tuberculosis strains. The MIC values of 25 RMP-susceptible (to 2 microg/ml) and 25 RMP-resistant (to 2 microg/ml) M. tuberculosis strains against RBU were determined by the Bactec TB 460 system. All of the RMP-susceptible strains were also susceptible to RBU (MIC < or = 1 microg/ml). Three out of 25 (12%) RMP-resistant strains were determined as susceptible to RBU. The high level cross-resistance (88%) obtained in this study highlights the importance of testing susceptibility to RBU prior to its inclusion in the tuberculosis treatment regimens at the Istanbul Faculty of Medicine.

Phenotypic variation and antifungal susceptibility patterns of Candida albicans strains isolated from neutropenic patients.

The aim of this study was to investigate the relationship between phenotypes of Candida albicans strains isolated from clinical specimens and the susceptibility of the strains to three antifungal agents, fluconazole, amphotericin B and flucytosine. Oropharyngeal, gastrointestinal and urogenital tract specimens were collected from 122 neutropenic patients who had received no previous prophylactic treatment. Each of 122 C. albicans strains recovered was found to express one of the six phenotypes: smooth, fuzzy, irregular, star, ring and stipple. The mean minimum inhibitory concentrations (MICs) of fluconazole was consistently higher for C. albicans strains expressing the stipple phenotype. The mean MICs for the six phenotypes of C. albicans strains ranged between 1.22 and 7.94 micrograms ml-1 for fluconazole, 0.99 and 2.55 micrograms ml-1 for amphotericin B and 1.23 and 1.83 micrograms ml-1 for flucytosine. The antifungal susceptibility of the stipple phenotype requires attention, especially in patients who are clinically unresponsive to fluconazole chemotherapy or in cases of life-threatening C. albicans infections of immunocompromised hosts. Long-term use of fluconazole may explain the outcome of the resistant stipple phenotype.

The epidemiology of onychomycoses in Istanbul, Turkey.

Between September 1995 and September 1997, 1840 patients attending our mycology department were suspected as having onychomycoses. Of the patients 985 were females and 855 were males. A total of 426 finger nail and 1414 toe nail scrapings were examined. Both microscopic and culture tests were carried out for each specimen. In 759 cases positive fungal cultures were found and 1081 cases were determined as negative. One fungal species was isolated from 715 specimens, in 44 of the cases two different species were found.