p53 mutation is rare in oral mucosa brushings from patients previously treated for a head and neck squamous cell carcinoma.

Mutations of the tumour suppressor gene p53 are common in human cancer, and seem to be an early event in head and neck squamous cell carcinomas. The aim of our study was to determine the status of the tumour suppressor gene p53 in the oral mucosa of patients previously treated for a head and neck squamous cell carcinoma, at risk of developing an oral squamous cell carcinoma, but without oral clinical lesions. Oral brushings from 87 patients were sequenced with matched genomic DNA.

[Prevalence of oral lesions by Candida sp.: Their varieties and serotypes in a population of patients with AIDS under a highly active antiretroviral therapy.].

The aim of this study has been to determine the prevalence of oral candidiasis and oral Candida carriers in an AIDS population under highly active antiretroviral therapy. Eighty-six AIDS patients treated with an antiretroviral combination (indinavir o ritonavir o saquinavir + zidovudine [AZT] + lamivudine [3TC]). Patients were grouped attending the predisposing factors for HIV infection in: intravenous drug users (IDU), heterosexuals, homosexuals, patients using hematological products or having unknown factors.

Comparative evaluation of ATB Fungus 2 and Sensititre YeastOne panels for testing in vitro Candida antifungal susceptibility.

ATB Fungus 2 and SensititreYeastOne are commercial methods for antifungal susceptibility testing of yeasts. The agreement between these two methods was assessed with a total of 133 Candida strains (60 Candida albicans, 18 Candida dubliniensis, 29 Candida glabrata, and 26 Candida krusei). MIC endpoints were established after 24 h of incubation at 36-/+1 degrees C by each method.

p16(INK4a) promoter hypermethylation in oral scrapings of oral squamous cell carcinoma risk patients.

Aberrant promoter hypermethylation is common in oral squamous cell carcinoma (OSCC) and may be useful as a marker for cancer cells. The aim of our study was to assess whether the detection of hypermethylation of the promoter region of p16(INK4a) in oral cytological samples could be a marker in patients with risk of developing an OSCC. Hypermethylation was detected in 20% (29/145) of the cases analyzed.

In vitro antifungal susceptibility testing of filamentous fungi with Sensititre Yeast One.

Sensititre is a colorimetric microdilution method for in vitro antifungal susceptibility testing based on the M27-A document (National Committee for Clinical Laboratory Standards) for yeasts. Difference between both methods is the presence of Alamar-blue and RPMI 1640 (glucose 2%) as culture medium. Antifungal susceptibility to amphotericin B, fluconazole, itraconazole, ketoconazole and flucytosine, 100 opportunistic filamentous fungi (Aspergillus spp.

Loss of expression of DNA repair enzyme MGMT in oral leukoplakia and early oral squamous cell carcinoma. A prognostic tool?

MGMT is a specific DNA repair enzyme that removes alkylating lesions and therefore plays an important role in maintaining normal cell physiology and genomic stability. Loss of expression of MGMT is associated with increased carcinogenic risk and sensitivity to methylating agents in different types of tumours. The expression of MGMT was immunohistochemically assessed in 12 normal oral mucosa, 38 oral leukoplakias and 33 early oral squamous cell carcinomas.

[In vitro activity of a liposomal nystatin formulation (Nyotran) against Cryptococcus neoformans].

The in vitro antifungal activity of a new liposomal nystatin formulation (NISTL, Nyotran, Aronex Ltd., EE.UU.

Applications of the oral scraped (exfoliative) cytology in oral cancer and precancer.

Scraped (exfoliative) cytology is a simple and harmless procedure, which has been a controversial technique according to its real validity in oral pathology. Lately it has re-emerged due to its application in oral precancer and cancer as a diagnostic and predictive method as well as for monitoring patients. New diagnostic techniques have been developed, such as "brush biopsy" and multiple molecular studies using the cells collected.

Antifungal activity of posaconazole compared with fluconazole and amphotericin B against yeasts from oropharyngeal candidiasis and other infections.

Objectives: The in vitro antifungal activity of posaconazole was compared with that of fluconazole and amphotericin B.

Materials And Methods: A microdilution method (M27-A2) was used with 331 clinical yeast isolates.

Results: The geometric mean MICs of posaconazole, fluconazole and amphotericin B were 0.

In-vitro activity of 5-fluorocytosine against 1,021 Spanish clinical isolates of Candida and other medically important yeasts.

The aim of this study was to determine the prevalence of primary resistance to 5-fluorocytosine (5FC) among clinical isolates of yeasts in Spain where this drug is not currently available for therapy. We have tested the in vitro activity of 5FC against 1,021 recent yeast clinical isolates, including 522 Candida albicans, 140 Candida parapsilosis, 68 Candida glabrata, 41 Candida dubliniensis, 50 Candida guilliermondii, 34 Candida tropicalis, 28 Candida krusei, 20 Candida famata, 11 Cryptococcus neoformans, 5 Cryptococcus albidus, 43 Rhodotorula spp., 24 Trichosporon spp.

Typing fungal isolates: molecular methods and computerized analysis.

Infections caused by fungi (mycoses) are increasingly reported in many countries owing to greater life expectancy associated with an increase in quality of medical and surgical procedures, as well as the emergence of diseases or infections that affect the immune system such as AIDS. Nosocomial outbreaks of fungal infections are sometimes reported, and typing is then necessary to find the reservoirs, analyze the modes of transmission, study the antifungal susceptibility patterns, and investigate the susceptibility of the host. In addition, the food industry is increasingly demanding typing methods that could help in selection of the best fungal strains, in order to incorporate them in the productive chains and augment the quality and security of food.

Changes in susceptibility to posaconazole in clinical isolates of Candida albicans.

Objectives: To characterize the molecular mechanisms responsible for reduced susceptibility to azoles in Candida albicans clinical isolates.

Materials And Methods: Seven sequential C. albicans isolates were cultured from an AIDS patient treated with posaconazole for refractory oropharyngeal candidiasis.

Comparison of in vitro antifungal activities of amphotericin B lipid complex with itraconazole against 708 clinical yeast isolates and opportunistic moulds determined by National Committee for Clinical Laboratory Standards methods M27-A and M38-P.

We compared the in vitro antifungal activity of amphotericin B lipid complex (ABLC) with that of itraconazole (ITZ) against 535 yeast strains and 173 opportunistic filamentous fungi by using a microdilution method (National Committee for Clinical Laboratory Standards M27-A and M38-P). The overall geometric mean MIC was 0.13 microg/ml and 0.

Heterogeneous mechanisms of azole resistance in Candida albicans clinical isolates from an HIV-infected patient on continuous fluconazole therapy for oropharyngeal candidosis.

Molecular mechanisms of azole resistance in Candida albicans include alterations in the target enzyme and increased efflux of drug, but the impact of specific treatment regimens on resistance has not been established. A patient with advanced AIDS was enrolled in a longitudinal study to receive continuous oral fluconazole (FLU) 200 mg/day for the treatment of oropharyngeal candidosis (OPC). Oral cultures were obtained at time of enrollment, during episodes of OPC and quarterly for surveillance.

[Activity of itraconazole against clinical isolates of Aspergillus spp. and Fusarium spp. determined by the M38-P NCCLS method].

The antifungal activity of itraconazole was studied in 101 clinical isolates of Aspergillus fumigatus, A. flavus, A. niger, A.

In vitro susceptibility of Candida dubliniensis to current and new antifungal agents.

Background: Candida dubliniensis is a recently described Candida species closely related to Candida albicans, which has been associated with oral candidiasis in HIV-infected patients. Fluconazole-resistant strains of C. dubliniensis are easily obtained in vitro and this fact could be a complication if this resistance develops during treatment with this drug.

Comparative in vitro antifungal activity of amphotericin B lipid complex, amphotericin B and fluconazole.

Amphotericin B (AMB) is considered the gold standard in the treatment of serious systemic mycoses in spite of its nephrotoxicity and adverse effects. Association with lipids enables larger doses of AMB to be given with a longer t((1/2)) and C(max), without the toxic effects at lower concentrations. Liposome-encapsulated AMB shows a lower affinity for mammalian cells and improves V(d), thus decreasing toxicity.

[Determination of the in vitro antifungal susceptibility of clinically important yeasts using the Sensititre system].

Using Sensititre (AccuMed, USA) we studied the in vitro antifungal activity of amphotericin B, fluconazole, itraconazole, ketoconazole and 5-fluorocytosine against 250 clinical yeast isolates taken from different hospitals, including Candida (151 C. albicans, 15 C. krusei, 14 C.

In-vitro antifungal activity of liposomal nystatin in comparison with nystatin, amphotericin B cholesteryl sulphate, liposomal amphotericin B, amphotericin B lipid complex, amphotericin B desoxycholate, fluconazole and itraconazole.

The in-vitro susceptibilities of 120 clinical isolates of yeasts to liposomal nystatin were compared with those to amphotericin B lipid complex (ABLC), liposomal amphotericin B (LAB), amphotericin B cholesteryl sulphate (ABCD), amphotericin B desoxycholate, nystatin, fluconazole and itraconazole. Yeast isolates examined included strains of Candida albicans, Candida parapsilosis, Candida glabrata, Candida krusei, Candida guilliermondii, Candida tropicalis, Candida kefyr, Candida viswanathii, Candida famata, Candida rugosa, Rhodotorula rubra, Trichosporon spp., Cryptococcus laurentii and Cryptococcus neoformans.