Effect of microwave polymerization on the thermomechanical and surface properties of ocular prosthetic acrylic resins.

BACKGROUND: Polymerization conditions affect the physical-mechanical properties of acrylic resins used for craniofacial prostheses. OBJECTIVE: The aim of this study was to evaluate the effect of microwave polymerization on the thermomechanical properties and surface morphology of ocular prostheses fabricated with polymethyl methacrylate (PMMA). METHODS: PMMA discs were polymerized with microwave energy and with conventional heat polymerization (CHP) method. Ocular prostheses were fabricated to determine whether there were changes according to the polymerization method. The surface morphology and roughness were observed under SEM and AFM. The Vickers Hardness number (VHN) and flexural strength were measured. Thermal properties were evaluated with TGA/DSC, and chemical composition with FTIR. RESULTS: The PMMA acrylic resin polymerized with microwave energy showed a smooth surface with some relief areas. In the internal surface of the ocular prosthesis with microwave energy the PMMA is more compact. The mean roughness values were higher and statistically significant with CHP (P < 0.05), while the surface hardness and flexural strength were higher with microwave energy (P < 0.05). CONCLUSION: There were no changes in the calorimetry with either method, TGA showed an exothermic peak around 120 °C with CHP method. PMMA polymerized with microwave energy improved the mechanical and surface properties of the ocular prostheses.

Does microwave and hydrogen peroxide disinfection reduce Candida albicans biofilm on polymethyl methacrylate denture surfaces?

STATEMENT OF PROBLEM: Whether the disinfection of polymethyl methacrylate (PMMA) dentures eliminates Candida albicans biofilm is unclear. PURPOSE: The purpose of this in vitro study was to determine the antimicrobial effect of immersion in hydrogen peroxide (H2O2) and subsequent application of microwaves on the formation of C albicans biofilm on the surface of polished and unpolished PMMA disks. MATERIAL AND METHODS: Polished and unpolished PMMA disks (n=40) were mounted in a Center for Disease Control (CDC) biofilm reactor by adding yeast-dextrose-peptone (YPD) broth inoculated with C albicans in a cell suspension for 24 hours. After this period, the PMMA disks (n=8) were disinfected with 5 different solutions: saline solution, 1% sodium hypochlorite (NaOCl), H2O2, H2O2 microwaved at 650 W for 3 minutes (H2O2/µw), and distilled water microwaved at 650 W for 3 minutes (H2O/µw). On the polished and unpolished surface of each disk, arbitrary fluorescence units (AFU) were quantified with the live/dead bacterial viability kit (Invitrogen) by using confocal laser scanning microscopy (CLSM) to evaluate 10 different areas of each surface; these were counted as the colony-forming units (CFUs). The mean values were compared by using the Mann-Whitney U test (α=.05). RESULTS: Polished surfaces disinfected with H2O2/µw obtained the lowest viable cells (9.76 AFU) and nonviable cells (12.46 AFU) compared with H2O/µw and H2O2. In the unpolished surface the lowest mean values of viable cells (14.64 AFU) and nonviable cells (12.46 AFU) were obtained for the PMMA disks disinfected with H2O/µw compared with H2O2/µw and H2O2. Both polished and unpolished disks showed significant difference (P<.05) compared with the group of PMMA disks immersed in saline solution. No CFUs were detected in the polished or unpolished PMMA disks immersed in H2O2/µw or in NaOCl. CONCLUSIONS: H2O2 alone did not eliminate the formation of the biofilm of C albicans; however, in combination with the use of the microwave at 650 W for 3 minutes, the biofilm formation of C albicans on polished surfaces was reduced. The number of AFUs of viable-nonviable cells and CFUs depended on whether the surfaces are polished or unpolished.

Frequency of Pathogenic Microorganisms in Removable Orthodontic Appliances and Oral Mucosa in Children.

OBJECTIVE: The aim of this study was to evaluate the frequency of Staphylococcus aureus, Pseudomonas aeruginosa, and Candida species in removable orthodontic appliances (ROA) and the support oral mucosa in children. STUDY DESIGN: The study participants comprised 55 patients aged 6-12 years requiring ROA. The samples of biofilm colonization from the support oral mucosa and the ROA were taken prior to the use of the ROA (T0) and 4 weeks (T1) after ROA placement. The biofilm samples were seeded on chromogenic culture plates and incubated for 24-48 h. RESULTS: The microbial species evaluated were not present in either the support oral mucosa nor in the ROA at T0. After 4 weeks, P. aeruginosa was found in the support oral mucosa with a frequency of 60%, Candida spp. with 30.9% and S. aureus with 89.09%; in the ROA, P. aeruginosa with 67.7%, Candida spp. with 32.7%, while S. aureus with 90.9%. In the ROA were found C. glabrata in 15 cases, C. albicans in 14 cases, C. tropicalis in two cases, and C. krusei in one case. In the oral mucosa there were 10 cases of C. glabrata, 14 cases of C. albicans, one case of C. tropicalis, and 0 cases of C. krusei. CONCLUSIONS: The frequency of S. aureus, P. aeruginosa, and Candida spp. increased after the orthodontic treatment in either the ROA and or in the support oral mucosa. There is a direct relation between the use of the ROA and the increase of periodontal-pathogenic microorganisms.

Antimicrobial effect of gold nanoparticles in the formation of the Staphylococcus aureus biofilm on a polyethylene surface.

The main of this study was to evaluate the inhibitory effect on the in vitro formation of the Staphylococcus aureus biofilm formed on a polyethylene (PE) surface with a nanostructured Gold (Au) coating for medical devices. An experimental in vitro study was carried out using PE discs with an Au nanoparticle coating (AuNPs) on one side (experimental group) and without coating on the other (control group); the discs were mounted in the CDC biofilm reactor adding broth of yeast-dextrose-peptone (YPD) sterile culture inoculated with S. aureus in a cell suspension (5 × 108 cells/ml). The specimens were evaluated at different times (6, 12, 24, 48, 72 h) and stained with the Live/Dead Bacterial Viability Kit (Invitrogen) for observation, analysis, and quantification with confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). The results showed that as evaluation time passed an increasing of S. aureus biofilm formation was observed in the control group, in the experimental group, a statistically significant biofilm inhibition was observed with respect to the AuNPs uncoated specimens (p ≤ 0.05) and showed a ratio of almost 4:1 viable/nonviable in the biofilm of the uncoated surfaces, with a difference > 5 Log10 in the CFU counts. The PE with AuNP coating showed an inhibitory effect on the biofilm formation of S. aureus.

Effect of Five Commercial Probiotic Formulations on Candida Albicans Growth: In Vitro Study.

PURPOSE: The objective was to evaluate the antagonistic effect of Lactobacillus and Bifidobacterium recovered from five commercial probiotics on the growth of C. albicans. STUDY DESIGN: The Lactobacillus and Bifidobacterium strains of five commercial probiotics were recovered and grown: Probio Hp+®, ProBiseis®, Lactipan®, Liolactil®, and Lacteol Fort®; 50 mg of each was hydrated and grown in Lactobacilli MRS (De Man, Rogosa and Sharpe) broth and incubated at 37°C with stirring (120 RPM) for 24 hours. Serial dilutions of 10-1 to 10-7 were made and viability was verified and quantified. For the antagonism tests, a suspension/inoculum of Lactobacillus strains recovered from each commercial preparation (4-30 × 109) and C. albicans ATCC 90028 (1.5-8 × 108) was prepared in MRS broth and incubated for 48 hours at 36°C, then plated on Dextrose Sabouraud Agar with Chloramphenicol and Rogosa Agar and the colony-forming units (CFU) were quantified. Additionally, viability was evaluated using the LIVE/DEAD® Yeast and Bacterial Viability kit. RESULTS: The probiotic that produced the highest acidity of the medium was Lactipan®, followed by Probiseis® and Liolactil®, while Probio Hp+® showed the least change. Probiseis® was determined to have the highest growth of probiotic bacteria and the highest inhibition on C. albicans, followed by Lactipan®; Liolactil® and ProbioHp+® showed the least effect. In fluorescence tests, ProBiseis® showed the best effect, followed by Liolactil® and Lactipan®; Probio Hp+® had less of an effect. CONCLUSIONS: Two commercial products (ProBiseis and Lactipan) whose formulations have L. acidophilus, L. casei, L. rhamnosus, L. plantarum, B. infantis, and S. thermophilus have a greater inhibitory effect on C. albicans ATCC 90028.

A few-layer graphene/chlorin e6 hybrid nanomaterial and its application in photodynamic therapy against Candida albicans.

The global emergence of multidrug resistance of fungal infections and the decline in the discovery of new antibiotics are increasingly prevalent causes of hospital-acquired infections, among other major challenges in the global health care sector. There is an urgent need to develop noninvasive, nontoxic, and new antinosocomial approaches that work more effectively and faster than current antibiotics. In this work, we report on a biocompatible hybrid nanomaterial composed of few-layer graphene and chlorin e6 (FLG-Ce6) for the photodynamic treatment (PDT) of Candida albicans. We show that the FLG-Ce6 hybrid nanomaterial displays enhanced reactive oxygen species (ROS) generation compared with Ce6. The enhancement is up to 5-fold when irradiated for 15 min at 632 nm with a red light-emitting diode (LED). The viability of C. albicans in the presence of FLG-Ce6 was measured 48 h after photoactivation. An antifungal effect was observed only when the culture/FLG-Ce6 hybrid was exposed to the light source. C. albicans is rendered completely unviable after exposure to ROS generated by the excited FLG-Ce6 hybrid nanomaterial. An increased PDT effect was observed with the FLG-Ce6 hybrid nanomaterial by a significant reduction in the viability of C. albicans, by up to 95%. This is a marked improvement compared to Ce6 without FLG, which reduces the viability of C. albicans to only 10%. The antifungal action of the hybrid nanomaterial can be activated by a synergistic mechanism of energy transfer of the absorbed light from Ce6 to FLG. The novel FLG-Ce6 hybrid nanomaterial in combination with the red LED light irradiation can be used in the development of a wide range of antinosocomial devices and coatings.

Short-term effect of a synbiotic in salivary viscosity and buffering capacity; a quasi-experimental study / Efecto a corto plazo de un simbiótico en la viscosidad y la capacidad tampón salival; un estudio cuasi experimental

Evaluate the effect of a synbiotic on salivary viscosity and buffer capacity. Materials and Methods: A follow-up one-week study was performed on 24 healthy volunteers in San Luis Potosí, Mexico, during July 2017. Volunteers must have had active tooth decay at the moment of study. All 24 patients were given a Lactiv® probiotic package, advising not to modify usual oral hygiene practices, and were followed up during 6 days. Primary output variable was salivary viscosity while the secondary was salivary buffer capacity. Salivary viscosity was assessed by using an Ostwald Pipette and buffer capacity with bromocresol purple. Results: A total of 8 male patients (33.3%) and 16 females (66.6%) patients were included, with an average age of 10.92 years. All the volunteers completed the study. Comparisons between pre- and post-treatment showed a decrease in salivary viscosity, while buffer capacity was showed to increase. Conclusion: The use of a synbiotic during a short period of time lowered the viscosity of saliva and increased salivary buffer capacity.

Evaluar el efecto de un sinbiótico sobre la viscosidad salival y la capacidad de tampón de la saliva. Materiales and Métodos: Se realizó un estudio de seguimiento de una semana en 24 voluntarios sanos en San Luis Potosí, México, durante julio de 2017. Los voluntarios cursaban caries dental activa en el momento del estudio. Los 24 pacientes recibieron un paquete de probióticos Lactiv®, fueron aconsejados a no modificar las prácticas habituales de higiene oral, y fueron seguidos durante 6 días. La variable primaria fue la viscosidad salival mientras que la secundaria fue la capacidad tampón. La viscosidad salival se evaluó usando una pipeta Ostwald y capacidad tampón con bromocresol púrpura. Resultados: Se incluyeron un total de 8 pacientes varones (33,3%) y 16 mujeres (66,6%), con una edad promedio de 10,92 años. Todos los voluntarios completaron el estudio. Las comparaciones entre el pretratamiento y el postratamiento mostraron una disminución de la viscosidad salival, mientras que se demostró que la capacidad del tampón aumentó. Conclusión: El uso de un sinbiótico durante un corto período de tiempo mostró un efecto sobre la disminución de la viscosidad y el aumento de la capacidad del tampón salival.

Glass coatings to enhance the interfacial bond strength between veneering ceramic and zirconia.

The purpose of this study was to investigate the tensile bond strength (TBS) and shear bond strength (SBS) between a zirconia core and fluoroapatite-pressed ceramic after the application of glass 46SP6 and AP40 via the ISO-17095:2013 methodology. Sintered zirconia beams (n = 120) were divided into four groups: (a) control: no treatment; (b) ZirL: IPS-E max ceram ZirLiner coating; (c) glass AP40 coating; and (d) glass 46SP6 coating. A fluoroapatite ceramic (IPS e.max Zir Press, Ivoclar Vivadent) beam was injected perpendicularly on top of each zirconia (Zenostar, Wieland Dental) beam forming a cross-bonded specimen. All groups were sub-divided into two for tensile and shear bond strength tests using a universal testing machine. Data were analyzed using the Kruskal-Wallis, Pearson Chi2, and Mann-Whitney U test (α = 0.05). The failure modes were measured using a stereomicroscope for each group. Scanning electron and atomic force microscopy were also employed. Zirconia surface modification with glass AP40 showed higher TBS values followed by the ZirL group with statistical differences (p < 0.05). SBS values showed no statistical differences between the groups. AFM analysis showed higher roughness values (Ra) in the 46SP6 and AP40 groups (p < 0.05). Glass coating AP40 exhibited promising bond strength results between zirconia and fluorapatite veneering ceramic, making it better for chemical and mechanical interlocking which may improve bilayered restorations longevity.

El expediente clínico electrónico: una opción con posibilidades ilimitadas / The electronic clinical file: an option with unlimited possibilities

El expediente clínico se define como el conjunto de datos médicos y clínicos ordenados y detallados en forma cronológica, que permiten al profesional de la salud plantear un diagnóstico sindrómico y nosológico, con su posterior pronóstico, para finalmente llevar un registro del desarrollo de un tratamiento. Refleja la capacidad resolutiva de la clínica o consultorio, así como la capacidad profesional de su personal, de ahí la importancia de tener un expediente clínico bien integrado, ordenado, completo, legible y en apego a la normatividad vigente (AU)

The clinical file is defined as a set of medical and clinical data, which are ordered and chronologically detailed, allows the health professional to identify a syndromic and nosological diagnosis, with a later prognosis, to finally make a treatment plan. It reflects the resolutive capacity and the professional capacity of the clinician and his staff. Therefore, it becomes a legal document of the greatest importance, having to have the characteristics of being well integrated, orderly, complete, legible and in compliance with current regulations (AU)

Differences by Resistotyping Between C. albicans Strains Isolated from the Oral Cavity of HIV+ and Seronegative Patients / Diferencias por resistotipificación entre cepas de C. albicans aisladas de la cavidad oral de pacientes VIH+ y seronegativos

Abstract Candida albicans is the etiological agent most frequently associated with oral candidiasis in human immunodeficiency virus (HIV) carriers. Strain typification is important to disease epidemiology, particularly with simple, low-cost methodologies such as resistotyping. The present study was designed to use resistotyping to identify possible phenotypic differences between C. albicans strains isolated from the oral cavity of HIV+ and HIV-seronegative patients. Analyses were run using resistotyping (boric acid, cetrimide, sodium periodate, sodium selenite and silver nitrate) to identify phenotypical differences between C. albicans. Descriptive statistics was performed. Of the 149 clones isolated from HIV+ patients the most frequent (47.0%) resistotype was ABCDE. The most frequent resistotype (64.8%) in the 74 clones from HIV-seronegative patients was --CDE. Phenotypic differences were identified between the strains isolated from each group. HIV+ patients exhibited greater strain diversity. Although it has limitations, resistotyping effectively identified differences between C. albicans strains.

Resumen Candida albicans es el agente etiológico más frecuentemente asociado con la candidiasis oral en portadores del virus de la inmunodeficiencia humana (VIH). La tipificación de la cepas es importante para conocer la epidemiología de la enfermedad, particularmente con metodologías simples y de bajo costo, como la resistotipificación. El presente estudio fue diseñado para identificar posibles diferencias fenotípicas por el método de resistotipificación entre cepas de C. albicans aisladas de la cavidad oral de pacientes VIH+ y seronegativos. Se realizó estadística descriptiva. Los análisis se realizaron utilizando resistotipificación (ácido bórico, cetrimida, peryodato de sodio, selenito de sodio y nitrato de plata) para identificar diferencias fenotípicas entre C. albicans. De las 149 clonas aisladas de pacientes VIH+, el resistotipo más frecuente (47.0%) fue ABCDE. El resistotipo más frecuente (64.8%) en las 74 clonas de pacientes seronegativos al VIH fue --CDE. Se identificaron diferencias fenotípicas entre las cepas aisladas de cada grupo. Los pacientes VIH + exhibieron una mayor diversidad de cepas. Aunque tiene limitaciones, la resistotipificación identificó de manera efectiva las diferencias entre las cepas de C. albicans.

The essential oil of Allium sativum as an alternative agent against Candida isolated from dental prostheses / Aceite esencial de Allium sativum como tratamiento alternativo contra aislamientos de Candida procedentes de prótesis dentales

Background. The colonization of the surfaces of dental prostheses by Candida albicans is associated with the development of denture stomatitis. In this context, the use of fluconazole has been proposed, but its disadvantage is microbial resistance. Meanwhile, the oil of Allium sativum has shown an effect in controlling biofilm formation by C. albicans. Aims. The objective of this study was to determine the antifungal activities of the essential oil of A. sativum and fluconazole against clinical isolates of Candida species obtained from rigid, acrylic-based partial or total dentures and to compare these agents’ effects on both biofilm and planktonic cells. Methods. A total of 48 clinical isolates obtained from the acrylic surface of partial or complete dentures were examined, and the following species were identified: C. albicans, Candida glabrata, Candida tropicalis, and Candida krusei. For each isolate, the antifungal activities of the essential oil of A. sativum and fluconazole against both biofilm and planktonic cells were evaluated using the Clinical & Laboratory Standards Institute (CLSI) M27-A3 method. The isolates were also evaluated by semiquantitative XTT reduction. Results. All planktonic Candida isolates were susceptible to the essential oil of A. sativum, whereas 4.2% were resistant to fluconazole. Regarding susceptibilities in biofilms, 43.8% of biofilms were resistant to A. sativum oil, and 91.7% were resistant to fluconazole. Conclusions. All planktonic cells of the different Candida species tested are susceptible to <1mg/ml A. sativum oil, and the majority are susceptible to fluconazole. Susceptibility decreases in biofilm cells, with increased resistance to fluconazole compared with A. sativum oil. The essential oil of A. sativum is thus active against clinical isolates of Candida species obtained from dentures, with effects on both biofilm and planktonic cells in vitro (AU)

Antecedentes. La colonización por parte de Candida albicans de las superficies de las prótesis dentales se asocia con el desarrollo de estomatitis. Se ha propuesto el uso de fluconazol, pero su desventaja es la resistencia microbiana. El aceite de Allium sativum ha mostrado su efectividad al controlar la formación de biopelícula de objetivos. Objetivos. Determinar la sensibilidad de cepas clínicas de especies de Candida, obtenidas de prótesis dentales parciales o totales rígidas de base acrílica, al aceite esencial de A. sativum y comparar su efecto en células planctónicas y en biopelícula. Métodos. Se incluyeron 48 cepas clínicas de la superficie acrílica de prótesis dentales totales o parciales, identificadas entre las siguientes especies: C. albicans, Candida glabrata, Candida tropicalis y Candida krusei. Se evaluó la sensibilidad de cada una al aceite esencial de A. sativum y al fluconazol mediante la metodología M27-A3 del CLSI, tanto sobre células planctónicas como en biopelícula, y mediante el método semicuantitativo de la reducción de XTT en el último caso. Resultados. Todas las cepas planctónicas de Candida fueron sensibles al aceite esencial de A.sativum, mientras que el 4,2% fue resistente al fluconazol. En cuanto a su sensibilidad en biopelícula, el 43,8% fue resistente a A. sativum y el 91,7% lo fue al fluconazol. Conclusiones. Todas las cepas en forma planctónica de las diferentes especies de Candida fueron sensibles a concentraciones inferiores a 1mg/ml del aceite esencial de A. sativum y en menor proporción a fluconazol. La sensibilidad disminuyó en las células en biopelícula, con mayor resistencia al fluconazol en comparación con el aceite esencial de A. sativum. Por tanto, el aceite esencial de A. sativum es activo frente a cepas clínicas de diferentes especies de Candida, obtenidas de dentaduras, con efectos en biopelícula y células planctónicas in vitro (AU)

The essential oil of Allium sativum as an alternative agent against Candida isolated from dental prostheses.

BACKGROUND: The colonization of the surfaces of dental prostheses by Candida albicans is associated with the development of denture stomatitis. In this context, the use of fluconazole has been proposed, but its disadvantage is microbial resistance. Meanwhile, the oil of Allium sativum has shown an effect in controlling biofilm formation by C. albicans. AIMS: The objective of this study was to determine the antifungal activities of the essential oil of A. sativum and fluconazole against clinical isolates of Candida species obtained from rigid, acrylic-based partial or total dentures and to compare these agents' effects on both biofilm and planktonic cells. METHODS: A total of 48 clinical isolates obtained from the acrylic surface of partial or complete dentures were examined, and the following species were identified: C. albicans, Candida glabrata, Candida tropicalis, and Candida krusei. For each isolate, the antifungal activities of the essential oil of A. sativum and fluconazole against both biofilm and planktonic cells were evaluated using the Clinical & Laboratory Standards Institute (CLSI) M27-A3 method. The isolates were also evaluated by semiquantitative XTT reduction. RESULTS: All planktonic Candida isolates were susceptible to the essential oil of A. sativum, whereas 4.2% were resistant to fluconazole. Regarding susceptibilities in biofilms, 43.8% of biofilms were resistant to A. sativum oil, and 91.7% were resistant to fluconazole. CONCLUSIONS: All planktonic cells of the different Candida species tested are susceptible to <1mg/ml A. sativum oil, and the majority are susceptible to fluconazole. Susceptibility decreases in biofilm cells, with increased resistance to fluconazole compared with A. sativum oil. The essential oil of A. sativum is thus active against clinical isolates of Candida species obtained from dentures, with effects on both biofilm and planktonic cells in vitro.

Oral Candida isolates and fluconazole susceptibility patterns in older Mexican women.

OBJECTIVES: To assess the epidemiologic and microbiologic profile and in vitro fluconazole susceptibility of yeasts isolated from the oral mucosa colonization/infection of elderly patients. BACKGROUND: It has been reported that in older adults increases the oral colonization by Candida particularly C. non-albicans, showing a decreased response to fluconazole, which increases the risk of recalcitrant local and disseminated candidiasis. MATERIALS AND METHODS: This was a prospective cross-sectional study conducted in 120 elderly patients. Oral samples were obtained of mucosal Candida colonization or infection by swabbing. Each sample was plated on CHROMagar(®)Candida and incubated (36±1.5°C) for two days. The yeast species were identified using the API(®)ID32-C-AUX. Fluconazole susceptibility was tested using a broth microdilution assay according to the CLSI methods. RESULTS: The yeast colonization/infection frequency in the total population was 65.8%. The frequency of the highest Candida carriers was 67.4% in the 70-79-year-old-group. Oral candidiasis was present in 20%, with a tendency to increase with age (33.3% of adults aged>80years), it was determined that the use of prosthesis is associated with a higher colonization rate (Chi2, p=0.011). The frequency of colonization/infection cases with more than one species showed a tendency to increase with age; 18.9% in the 60-69 year-old-group, 20.9% in the 70-79-year-old-group and 29.2% in the ≥80 year-old-group. About fluconazole susceptibility: for C. albicans, 20.3%, about Candida non-albicans species 15.3% were dose dependently susceptible (DDS) and 17.9% were resistant. CONCLUSIONS: After 80 years of age, there is a considerable increase in Candida non-albicans species and a reduced susceptibility to fluconazole.

Susceptibilidad in vitro de Candida albicans y no albicans Aisladas de Prótesis Dentales de Pacientes con Estomatitis Protésica a Tres Sustancias de Desinfección / In vitro Susceptibility of Candida albicans and Non-albicans Isolated fro Dental Prothesis in Patients with Denture Stomatitis to Three Disinfectants

A pesar del gran número de productos disponibles para la limpieza de prótesis dentales, el 60% de los portadores hace uso de ellos, posiblemente por la situación económica. El objetivo fue determinar la susceptibilidad antifúngica in vitro que presenta Candida y sus especies a tres sustancias utilizadas para la desinfección de prótesis (hipoclorito de sodio, ácido acético y solución de superoxidación). Se obtuvieron aislados clínicos de Candida de pacientes portadores de prótesis diagnosticados con estomatitis protésica, para su posterior estudio de susceptibilidad in vitro a las diferentes sustancias. El hipoclorito de sodio al 0,5% mostró in vitro una mayor inhibición para las cepas de Candida albicans y Candida no albicans. El ácido acético y la solución de superoxidación no mostraron inhibición in vitro frente a ambas cepas. El hipoclorito de sodio al 0,5% tiene un efecto inhibitorio in vitro sobre las cepas de C. albicans y Candida no albicans.

Despite the large number of products available for denture cleaning, less than 60% of denture wearers use them, possibly due to the economic situation. The aims were to determine the in vitro anti-fungal susceptibility of Candida species to three denture disinfectants (Sodium hypochlorite, acetic acid and super oxidized solution). Clinical isolates were obtained from denture wearers diagnosed with denture stomatitis for its posterior in vitro susceptibility study to the different substances. 0.5% Sodium hypochlorite showed the higher in vitro inhibitory effect on Candida albicans and non-albicans. Acetic acid and super oxidized solution showed no inhibition in both species. 0.5% Sodium hypochlorite has an in vitro inhibitory effect on Candida species.

Oral colonisation and infection by Candida sp. in diabetic and non-diabetic patients with chronic kidney disease on dialysis.

INTRODUCTION: Oral candidiasis (OC) is a common opportunistic infection in immunocompromised patients. Species identification is sometimes important for treatment. objective: to determine the prevalence of different Candida species colonising or infecting the oral mucosa (OM) of diabetic (DM) and non-diabetic (non-DM) chronic kidney disease patients, comparing both groups and exploring potential risk factors. METHODS: 56 DM and 80 non-DM patients on chronic dialysis were examined. OM swabs were cultured on Sabouraud dextrose agar plates. Candida species were identified with API® galleries. OC was confirmed by exfoliative cytology. Statistical associations were analysed using χ2, Fisher's exact test (ET), and multiple logistic regression. RESULTS: Candida prevalence was 43.4%: 53.6% DM and 36.3% non-DM, (p=.045). The species identified were C. albicans 74.6%, C. glabrata 22.0%, C. tropicalis 15.2%, C. parapsilosis 3.4 %, C. kefyr 3.4% and C. famata 1.7% without difference between groups. DM patients had a higher xerostomia prevalence (p=.002) and lower salivary flow (p=.008) and lower serum albumin (p=.018). 16.9% of patients had OC, 23.2% DM compared with 12.5% non-DM, (p=.101). The following were associated with the presence of Candida in the OM: the use of dental prostheses (odds ratio [OR] 25.6, 95% confidence interval [CI] 2.5 to 253, P=.001), xerostomia (OR 9.6, 95% CI 2.4 to 38.1, P=.001) and low serum albumin values (OR 0.41, 95% CI 0.22 to 0.98, P=.044). CONCLUSIONS: The presence of Candida sp. in the OM was associated with dental prostheses, xerostomia and low serum albumin.

Biofilm formation by oral clinical isolates of Candida species.

We have conducted a longitudinal study to quantify biofilms in oral clinical isolates of Candida species (spp.) from adults with local and systemic predisposing factors for candidiasis. A total of 69 yeast isolates from 63 Mexican patients were evaluated. These isolates (39 C. albicans, 15 C. tropicalis, 7 C. glabrata, 4 C. krusei, 1 C. lusitaniae, 1 C. kefyr, 1 C. guilliermondii and 1 C. pulcherrima) were obtained from two clinical sites: 62.3% (n=43) from the oral mucosa of totally and partially edentulous patients, and 37.7% (n=26) from the oral mucosa of diabetics. In addition, Candida ATCC strains were used as controls for each experiment. The kinetics of biofilm formation were measured by 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazolium hydroxide [XTT] reduction; each isolate was tested at 6, 12 and 24h. Biofilm formation is dependent on the Candida spp. and its clinical origin. On average, the oral isolates of C. glabrata are strong biofilm producers, whereas C. albicans and C. tropicalis are moderate producers. The most common species in our population was C. albicans. While the kinetics of C. albicans biofilm formation varies between oral isolates, it generally maintains steady growth from 2 to 48h, when it reaches its maximum growth.

Ensayo de formación y cuantificación de biopelículas mixtas de Candida albicans y Staphylococcus aureus / Formation and quantification assay of Candida albicans and Staphylococcus aureus mixed biofilm

En el presente estudio se cuantificó la producción de biopelículas individuales y mixtas de Candida albicans y Staphylococcus aureus para determinar si dichas biopelículas mixtas se favorecen sinérgicamente. Los ensayos se realizaron utilizando placas de microtitulación de poliestireno de 96 pocillos de fondo plano, se determinó la actividad metabólica de las células en la biopelícula por medio de la reducción enzimática de una sal de tetrazolio (XTT) a través de los cambios colorimétricos que fueron medidos a 490nm. Para visualizar las biopelículas de cada microorganismo y su cinética de crecimiento se utilizo microscopia láser confocal. La mayor formación de biopelícula se observó en las biopelículas mixtas, seguida de las de Candida albicans y, por último, la menor producción la obtuvo Staphylococcus aureus, lo cual nos sugiere la presencia de una relación sinérgica entre los microorganismos ensayados(AU)

This study quantifies the production of single and mixed biofilms of Candida albicans and Staphylococcus aureus to determine if such mixed biofilms have synergistic effects. Assays were performed using polystyrene microtitre plates of 96 wells, metabolic activity was measured by the enzymatic reduction of a tetrazolium salt (XTT) and colorimetric changes were measured at 490nm. Confocal scanning laser microscopy was used to visualise the biofilms of each microorganism and its growth kinetics. The highest levels of biofilm formation were observed in mixed biofilms, followed by those of Candida albicans only, with the lowest levels of biofilm formation being detected for Staphylococcus aureus; all together these results suggest a synergistic relationship between the tested microorganisms(AU)

[Oral Candida in Mexican children with malnutrition, social marginalization, or HIV/AIDS]. / Candida bucal en niños mexicanos con VIH/sida, desnutrición o marginación social.

OBJECTIVE: Determine the frequency of candida in the oral cavity of children with a risk of developing opportunistic infections, and establish if there is an association between the frequency of this oral colonization and three categories of at-risk populations. METHODS: Four infant population groups in Mexico were studied: an HIV/AIDS group undergoing highly active antiretroviral therapy (35 girls and 25 boys); a malnourished group (26 girls and 29 boys); a group from the Tarahumara indigenous people, one of the poorest ethnic populations in the country (37 girls and 20 boys); and a control group (8 girls and 21 boys in apparently good health). The children with HIV/AIDS were immunologically and virologically classified according to the EC Clearinghouse criteria, while malnutrition was determined through the World Health Organization's weight/height index. A sample of oral mucosa was taken with a sterile swab, which was incubated in Sabouraud dextrose agar and in Candida CHROMagar®. The species of candida were confirmed through the API ID32C test. RESULTS: The HIV/AIDS and malnutrition groups showed the higher frequency of Candida spps (51.7% and 38.2%, respectively), while the frequency level in the Tarahumara group was similar to that of the control group (17.5% versus 10.3%). With regard to the species of candida, the malnutrition group had the greatest diversity: C. albicans, C. tropical, C. krusei, and C. glabrata. CONCLUSIONS: The children with HIV/AIDS and malnutrition require strategies designed to reduce oral candidal colonization and reduce the risk of opportunistic infections.

[Formation and quantification assay of Candida albicans and Staphylococcus aureus mixed biofilm]. / Ensayo de formación y cuantificación de biopelículas mixtas de Candida albicans y Staphylococcus aureus.

This study quantifies the production of single and mixed biofilms of Candida albicans and Staphylococcus aureus to determine if such mixed biofilms have synergistic effects. Assays were performed using polystyrene microtitre plates of 96 wells, metabolic activity was measured by the enzymatic reduction of a tetrazolium salt (XTT) and colorimetric changes were measured at 490 nm. Confocal scanning laser microscopy was used to visualise the biofilms of each microorganism and its growth kinetics. The highest levels of biofilm formation were observed in mixed biofilms, followed by those of Candida albicans only, with the lowest levels of biofilm formation being detected for Staphylococcus aureus; all together these results suggest a synergistic relationship between the tested microorganisms.

Candida bucal en niños mexicanos con VIH/sida, desnutrición o marginación social / Oral candida in Mexican children with malnutrition, social marginalization, or HIV/AIDS

OBJETIVO: Determinar la frecuencia de Candida en cavidad bucal de niños con riesgo de desarrollar infecciones oportunistas y establecer si existe asociación entre la frecuencia de esta colonización bucal y tres tipos de población en riesgo. MÉTODOS: Se estudiaron cuatro grupos de población infantil de México: grupo VIH/sida bajo terapia antirretroviral altamente activa (TAAA) (35 niñas y 25 niños); grupo desnutrición (26 niñas y 29 niños); grupo tarahumara (37 niñas y 20 niños), una de las poblaciones étnicas más pobres del país, y grupo control (8 niñas y 21 niños aparentemente sanos). Los niños con VIH/sida fueron inmunológica y virológicamente clasificados según los criterios de EC-Clearinghouse, mientras que la desnutrición fue determinada a través del índice peso/talla de la Organización Mundial de la Salud. Se tomó una muestra de la mucosa bucal con hisopo estéril, que fue incubada en agar dextrosa Sabouraud y en CHROMagar-Candida®. Las especies de Candida se confirmaron con la prueba API ID32C. RESULTADOS: Los grupos VIH/sida y desnutrición mostraron la frecuencia más alta de Candida spp. (51,7 por ciento y 38,2 por ciento, respectivamente) mientras que el grupo tarahumara presenta una frecuencia semejante a la del grupo control (17,5 por ciento vs 10,3 por ciento). Respecto a las especies de Candida, el grupo desnutrición mostró la mayor diversidad: C. albicans, C. tropicalis, C. krusei y C. glabrata. CONCLUSIONES: Los infantes con inmunodeficiencia y con desnutrición requieren de estrategias diseñadas para disminuir la colonización bucal candidal y disminuir el riesgo de infecciones oportunistas.

OBJECTIVE: Determine the frequency of candida in the oral cavity of children with a risk of developing opportunistic infections, and establish if there is an association between the frequency of this oral colonization and three categories of at-risk populations. METHODS: Four infant population groups in Mexico were studied: an HIV/AIDS group undergoing highly active antiretroviral therapy (35 girls and 25 boys); a malnourished group (26 girls and 29 boys); a group from the Tarahumara indigenous people, one of the poorest ethnic populations in the country (37 girls and 20 boys); and a control group (8 girls and 21 boys in apparently good health). The children with HIV/AIDS were immunologically and virologically classified according to the EC Clearinghouse criteria, while malnutrition was determined through the World Health Organization's weight/height index. A sample of oral mucosa was taken with a sterile swab, which was incubated in Sabouraud dextrose agar and in Candida CHROMagar®. The species of candida were confirmed through the API ID32C test. RESULTS: The HIV/AIDS and malnutrition groups showed the higher frequency of Candida spps (51.7 percent and 38.2 percent, respectively), while the frequency level in the Tarahumara group was similar to that of the control group (17.5 percent versus 10.3 percent). With regard to the species of candida, the malnutrition group had the greatest diversity: C. albicans, C. tropical, C. krusei, and C. glabrata. CONCLUSIONS: The children with HIV/AIDS and malnutrition require strategies designed to reduce oral candidal colonization and reduce the risk of opportunistic infections.