Candida

A 24-year-old male patient with acute myeloid leukemia (AML), who had been in remission for 18 months following the completion of chemotherapy, presented with fatigue and nasal bleeding. He was found to have pancytopenia, and bone marrow aspiration showed relapsed AML. He was given high-dose sequential chemotherapy consisting of cytosine arabinoside, 500 mg/m 2 per day as a 24-h continuous infusion, idarubicin, 12 mg/m 2 per day on days 1-3, etoposide, 200 mg/m 2 per day as a 24-h continuous infusion on days 8-10, and granulocyte colony-stimulating factor (G-CSF), 5 mg/kg per day subcutaneously, starting from day 12 until absolute neutrophil recovery above 1000/mL. The patient became neutropenic, with a count below 100/mL, on the 5th day of chemotherapy. He was pyrexial on the next day, with a temperature of 39 8C, without any localizing symptoms or signs of infection. Blood cultures were taken, and chest X-ray was normal. Empirical antibiotic therapy with piperacillin-tazobactam was commenced, and vancomycin was added 48 h later, when no response was obtained. Examination revealed widespread oral mucositis on the fourth day of the febrile neutropenic episode. Blood cultures, which had been taken every other febrile day, revealed extended-spectrum b-lactamase-producing Escherichia coli on the seventh day of pyrexia, and meropenem and amikacin were substituted for piperacillin-tazobactam.

Six yeast strains of a novel anamorphic yeast species were isolated from natural samples collected in Thailand (RV60 T and LYSM9), Taiwan (SC5L04 and GE19S05), and Japan (JCM 11058 and JCM 11059). Analysis of the D1/D2 domain of the large subunit rRNA gene sequences revealed that the sequences of five strains (LYSM9, SC5L04, GE19S05, JCM 11058, and JCM 11059) were identical and differed from the sequence of strain RV60 T by only one nucleotide substitution. The closest recognized species in terms of pairwise sequence similarity was Candida abiesophila, but the level of nucleotide substitution (14.2-14.3%) was sufficient to justify the description of a separate species. Phenotypic characteristics of the six strains were almost the same except for two strains from Japan, which showed the ability to ferment glucose and grew in the presence of 10% NaCl and 5% glucose while the others did not. The phenotypic characteristics of the six strains included proliferation by multilateral budding, absence of ascospores, arthrospores, and ballistospores, and negative Diazonium blue B and urease tests. The major ubiquinone was Q-7. On the basis of the above findings, the six strains were assigned to a single novel species of Candida, for which the name Candida asiatica sp. nov. is proposed. The type strain is RV60 T (BCC 25966 T = NBRC 103863 T = CBS 10863 T ).

Background and objectives: The incidence of candiduria caused by Candida spp. has increased in recent years, particularly in hospitalized patients. Candiduria is most commonly caused by Candida albicans; however, an increase in the prevalence of non-albicans species has been observed during last decades. This study aimed at molecular identification of Candida species isolated from candiduria in hospitalized patients. Methods: This cross-sectional study was conducted on 530 hospitalized patients in two hospitals in the Mazandaran Province, Iran. Midstream urine specimens were collected and then cultured on CHROMagar Candida medium. Molecular identification of common Candida species was carried out using the polymerase chain reaction-restriction fragment length polymorphism method after enzymatic digestion with MspI. C. albicans and Candida parapsilosis species complexes were identified by amplification of the HWP1 and intein-containing vacuolar ATPase precursor genes, respectively. Results: The frequency of candiduria was estimated at 14% among hospitalized patients. Of 74 samples positive for candiduria, 65 (87.8%) were isolated from females. The most common predisposing factor to candiduria was diabetes (n=36; 48.6%). The most frequent isolates were C. albicans complex (n=44; 59.4%), followed by Candida glabrata (n= 16; 21.6%), Candida tropicalis (n= 10; 13.5%), Candida Krusei (n= 3; 4%) and C. parapsilosis (n= 1; 1.3%). Conclusion: Based on the results, the conventional and molecular methods produced similar results for identification of Candida species. However, accurate identification of Candida spp. requires the use of molecular techniques such as PCR-RFLP, HWP1, and intein-containing vacuolar ATPase precursor genes. Nevertheless, chromogenic methods such as CHROMagar Candida can be used for diagnosis of Candida spp. in laboratories with limited resources.

a r c h i v e s o f o r a l b i o l o g y 5 6 ( 2 0 1 1 ) 1 0 9 8 -1 1 0 5 a b s t r a c t Objectives: The aims of this study were to evaluate periodontal conditions and identify the presence of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis and Tannerella forsythia, and four different species of Candida (C. albicans, C. dubliniensis, C. glabrata and C. tropicalis) in periodontal pockets and furcation sites of insulin-dependent type 2 diabetic and non-diabetic patients with generalised chronic periodontitis.

Purpose: This study aimed to investigate the antimicrobial properties and cytotoxicity of the monomer methacryloyloxyundecylpyridinium bromide (MUPB), an antiseptic agent capable of copolymerizing with denture base acrylic resins. Materials and Methods: The antimicrobial activity of MUPB was tested against the species Candida albicans, Candida dubliniensis, Candida glabrata, Lactobacillus casei, Staphylococcus aureus, and Streptococcus mutans. The minimum inhibitory and fungicidal/bactericidal concentrations (MIC, MFC/MBC) of MUPB were determined by serial dilutions in comparison with cetylpyridinium chloride (CPC). The cytotoxic effects of MUPB at concentrations ranging from 0.01 to 1 g/L were assessed by MTT test on L929 cells and compared with methyl methacrylate (MMA). The antimicrobial activity of copolymerized MUPB was tested by means of acrylic resin specimens containing three concentrations of the monomer (0, 0.3, 0.6% w/w). Activity was quantified by means of a disc diffusion test and a quantification of adhered planktonic cells. Statistical analysis employed the Mann-Whitney test for MIC and MFC/MBC, and ANOVA for the microbial adherence test (α = 0.05). Results: MUBP presented lower MIC values when compared with CPC, although differences were significant for C. dubliniensis and S. mutans only (p = 0.046 and 0.043, respectively). MFC/MBC values were similar for all species except C. albicans; in that case, MUPB presented significantly higher values (p = 0.046). MUPB presented higher cytotoxicity than MMA for all tested concentrations (p < 0.001) except at 0.01 g/L. Irrespective of the concentration incorporated and species, there was no inhibition halo around the specimens. The incorporation of MUPB influenced the adhesion of C. albicans only (p = 0.003), with lower CFU counts for the 0.6% group. Conclusions: It was concluded that non-polymerized MUPB has an antimicrobial capacity close to that of CPC and high cytotoxicity when compared with MMA. The antimicrobial activity of MUPB after incorporation within a denture base acrylic resin did not depend on its elution, but was shown to be restricted to C. albicans.

A concentric draft tube jet loop bioreactor (10.5 m 3 ) was used to study the influence of aerated liquid height (above the draft tube) on the amount of surfactant addition allowable without foaming. Sodium lauryl sulfate (SLS) and defatted soybean flour in tap water were used as model artificial media. The amount of surfactant required to develop foaming and the maximum gas holdup achieved prior to foaming were notably influenced by aerated liquid height. Decreasing the aerated liquid height from 1.50 to 0.05 m increased the amount of SLS allowed without foaming from 2.2 to 12.1 g, the gas holdup in the riser from 0.18 to 0.31 and the gas holdup in the downcomer from 0.12 to 0.25. Similar behavior was observed for soybean flour. Decreasing the aerated liquid height from 1.45 to 0.05 m increased the amount of soybean flour allowed without foaming from 822 to 3200 g, the gas holdup in the riser from 0.17 to 0.26 and the gas holdup in the downcomer from 0.10 to 0.19. Data from a representative continuous yeast culture are reported to show that operation at low aerated liquid heights (0.5 m) can also be used to produce a culture broth with large gas holdup and oxygen transfer but without foaming.

Candida infections (candidiasis) are the most prevalent opportunistic fungal infection on humans and, as such, a major public health problem. In recent decades, candidiasis has been associated to Candida species other than Candida albicans. Moreover, biofilms have been considered the most prevalent growth form of Candida cells and a strong causative agent of the intensification of antifungal resistance. As yet, no specific resistance factor has been identified as the sole responsible for the increased recalcitrance to antifungal agents exhibited by biofilms. Instead, biofilm antifungal resistance is a complex multifactorial phenomenon, which still remains to be fully elucidated and understood. The different mechanisms, which may be responsible for the intrinsic resistance of Candida species biofilms, include the high density of cells within the biofilm, the growth and nutrient limitation, the effects of the biofilm matrix, the presence of persister cells, the antifungal resistance gene expression and the increase of sterols on the membrane of biofilm cells. Thus, this review intends to provide information on the recent advances about Candida species biofilm antifungal resistance and its implication on intensification of the candidiasis.

The stilbenoid resveratrol (1) was subjected to regioselective acetylation catalysed by Candida antarctica lipase (CAL) to obtain 4&#39;-acetylresveratrol (2). CAL biocatalysed regioselective alcoholysis of 3,5,4&#39;-triacetylresveratrol (3), 3,5,4&#39;-tributanoylresveratrol (6), and 3, 4, 5&#39;-trioctanoylresveratrol (9) afforded derivatives 4, 5, 7, 8, 10, and 11. Further resveratrol analogues (12-18) were obtained through methylation and hydrogenation reactions, whereas the 3,4,4&#39;-trimethoxystilbene (19) was obtained by complete synthesis. Resveratrol and its lipophylic analogues were subjected to cell-growth inhibition bioassays towards DU-145 human prostate cancer cells. Compounds 2-19 showed cell-growth inhibition activity comparable to or higher than resveratrol (GI(50)=24.09 microM), displaying low or very low toxicity against non-tumorigenic human fibroblast cells. Comparison of the trimethoxy stilbenes 12 (GI(50)=2.92 microM) and 19 (GI(50)=25.39 microM) indicates t...