Distribución de lesiones bucales producidas por Candida albicans en pacientes VIH/SIDA / Distribution of oral lesions produced by Candida albicans in HIV patients

Antecedentes: La candidiasis orofaríngea es la infección fúngica oportunista más frecuente en pacientes infectados por VIH. Clínicamente se puede presentar como queilitis angular, eritematosa, pseudomembranosa e hiperplásica. Objetivo. En el presente estudio se analizó la distribución de lesiones candidiásicas y su ubicación en la cavidad bucal en 29 pacientes VIH positivo. Método. Los pacientes fueron evaluados y controlados en el Servicio de Dermatología del Hospital Regional de Talca y se analizaron sus lesiones a nivel bucal y se tomaron muestras que permitieron aislar Candida albicans. Resultados y conclusiones. La candidiasis pseudomembranosa fue encontrada en mayor porcentaje (47.1 por ciento) y su principal ubicación fue en el paladar, la candidiasis eritematosa, la segunda más frecuente (45.1 por ciento) y su principal ubicación fue el dorso de la lengua. La queilitis angular se presentó el menor porcentaje (7.8 por ciento) y no se encontraron lesiones de tipo hiperplásica. Existe una fuerte asociación entre el tipo de variante clínica de candidiasis oral y su ubicación en la cavidad oral.

Background. The oropharyngeal candidiasis is the most common opportunistic fungal infection in HIV-infected patients. Clinically can be presented as angular cheilitis, erythematous, pseudomembranous and hyperplastic. Aims. The present study analyzed the clinical types of oral candidiasis and its location in the oral cavity in 29 HIV positive patients Methods. Patients were evaluated and controlled in a dermatology department of the Hospital Regional de Talca and analyzed their lesions at the oral level and samples for isolating Candida albicans. Results and conclusions. Pseudomembranous candidiasis was found in highest percentage (47.1 percent) and its main location was on the palate, erythematous candidiasis, the second most frequent (45.1 percent) and its principal location was the back of the tongue. Angular cheilitis was presented the lowest percentage (7.8 percent) and there were no hyperplastic type lesion. There is a strong association between the variant type of clinic oral candidiasis and its location in the oral cavity.

Purificación y caracterización parcial de una sustancia por Staphylococcus aureus con actividad antagónica sobre Listeria monocytogenes / Purification and partial characterization of an antimicrobial substance produced by Staphylococcus aureus with activity over Listeria monocytogenes

Staphylococcus aureus, a recognized human and animal pathogen is capable of producing various exoproteins, a process mediated by the mechanism of quorum sensing. This organism is screened in processed foods, and can produce food poisons. S. aureus is known for its ability to produce antimicrobial substances (bacteriocins) active against Listeria monocytogenes is the major pathogen in contamination of processed food and responsible of listeriosis. The aim of this research was to detect, purify and characterize partially an antimicrobial substance produced by S. aureus strain active against L. monocytogenes. In this investigation 46 S. aureus strains isolated from processed foods were studied. Activity was determined against L. monocytogenes by agar diffusion techniques. The partial purification and and characterization of antimicrobial substance was realized by molecular exclusion chromatography and polyacrylamide gel electrophoresis under denaturing and nondenaturing condictions. The antimicrobial substance that showed a molecular weight of 3.5 kDa approximately was resistant to different temperatures and wide pHs range. The antimicrobial substance could be classified as bacteriocins type II, subclass IIa. Future studies could be contributed to the possible use of the antimicrobial substance as food biopreservant.

[A new case of rhinosporidiosis in Chile]. / Un nuevo caso clínico de rinosporidiosis en Chile.

BACKGROUND: Rhinosporidiosis is a chronic, granulomatous, and non-contagious infection, in which highly vascularized polyps (mainly present in the nasal cavity) appear. These polyps usually bleed easily. AIMS: To present the case of a 14 year-old male suffering from an obstruction and injury of the right nostril due to a polypoid shaped-lesion with a raspberry-like appearance. METHODS: A wide surgery resection of the base of the lesion was performed, as well as a standard histopathology procedure, including microscopic analysis with haematoxylin-eosin and Grocott staining. RESULTS AND CONCLUSIONS: The histopathology report indicated that the chronic inflammatory polyp was compatible with rhinosporidiosis.

Brettanomyces, un contaminante en nuestras viñas / Brettanomyces, a contaminant in our vineyards

Uno de los avances de la enología moderna es el reconocimiento de la importancia de la levadura como un agente imprescindible para la adecuada obtención de vino. El proceso de fermentación es dinámico y existe un recambio de especies de levaduras desde el principio al final de la fermentación. Sin embargo, una de ellas, Brettanomyces, puede contaminar los caldos, alterando las cualidades aromáticas y de sabor del vino, provocando en algunos casos la pérdida del producto vinificado.Además de una importante pérdida económica, cifras extraoficiales indican que hasta un 5 por ciento de la producción nacional se pierde cada año producto de este hongo; el monto en pérdidas, sólo en vino embotellado, podría llegar a los US$30.000.000. La reacción en cadena de la polimerasa (PCR, Polimerase chain reaction) puede ser utilizada para detectar diminutas cantidades de ADN de un microorganismo. Esta técnica permite detectar este contaminante en no más de 24 horas, presenta una alta sensibilidad, necesitándose una cantidad ínfima de microorganismos en la muestra (1-100) levaduras por mL. El diagnóstico oportuno de la contaminación de los vinos por esta levadura permitiría adoptar medidas que controlen la proliferación de este contaminante, reduciendo las pérdidas del producto.

Effects of the bacteriocin PsVP-10 produced by Pseudomonas sp. on sensitive bacterial strains.

The bacteriocin PsVP-10 is a 2.6 Kda peptide which was isolated and purified from Pseudomonas sp. This bacteriocin possesses lethal activity over Enterococcus faecalis, Salmonella typhimurium and Shigella flexneri. The experimental assays showed that the bacteriocin is able to be adsorbed by all cells of these bacterial species and also by their isolated cell walls. It was observed that the resistant mutants and their respective cell walls are unable to adsorb the bacteriocin. Assays performed with spheroplasts obtained from sensitive bacterial species and their resistant mutants show a rapid lethal effect of the bacteriocin PsVP-10. This results indicated furthermore, it is also shown that the optimal pH and temperature for the adsorption were 7.2 and 37 degrees C, respectively. The study carried out with organic solvents like methanol, ethanol, isopropanol and the detergents sodium dodecyl sulfate and triton X-100 showed a moderate inhibition of the bacteriocin lethal action for the Gram negative cells. The enzymes lysozime, protease XIV and trypsine type III-S did not present any effect over the adsorption capacity of the bacteriocin with any of the bacterial species studied.