In vitro effect photodynamic therapy with differents photosensitizers on cariogenic microorganisms.

BACKGROUND: Antimicrobial photodynamic therapy has been proposed as an alternative to suppress subgingival species. This results from the balance among Streptococcus sanguis, Streptococcus mutans and Candida albicans in the dental biofilm. Not all the photosensitizers have the same photodynamic effect against the different microorganims. The objective of this study is to compare in vitro the photodynamic effect of methylene blue (MB), rose Bengal (RB) and curcumin (CUR) in combination with white light on the cariogenic microorganism S. mutans, S. sanguis and C. albicans. RESULTS: Photodynamic therapy with MB, RB and CUR inhibited 6 log 10 the growth of both bacteria but at different concentrations: 0.31-0.62 µg/ml and 0.62-1.25 µg/ml RB were needed to photoinactivate S. mutans and S. sanguis, respectively; 1.25-2.5 µg/ml MB for both species; whereas higher CUR concentrations (80-160 µg/ml and 160-320 µg/ml) were required to obtain the same reduction in S. mutans and S. sanguis viability respectively. The minimal fungicidal concentration of MB for 5 log10 CFU reduction (4.5 McFarland) was 80-160 µg/ml, whereas for RB it ranged between 320 and 640 µg/ml. For CUR, even the maximum studied concentration (1280 µg/ml) did not reach that inhibition. Incubation time had no effect in all experiments. CONCLUSIONS: Photodynamic therapy with RB, MB and CUR and white light is effective in killing S. mutans and S. sanguis strains, although MB and RB are more efficient than CUR. C. albicans required higher concentrations of all photosensitizers to obtain a fungicidal effect, being MB the most efficient and CUR ineffective.

Tumor fibroso solitario de la próstata / Solitary fibrous tumor of the prostate

No disponible

Fullerene C60-silver nanoparticles hybrid structures: optical and photoelectric characterization.

A detailed optical and photoelectric characterization of pristine fullerene C60 films deposited onto n-silicon substrates (C60/Si), C60 films crosslinked by means of the solvent-free chemical functionalization with 1,8-diaminooctane (C60-DA/Si), and the pristine and crosslinked films decorated with silver nanoparticles (C60-Ag/Si and C60-DA-Ag/Si), was carried out. The reflectance spectra obtained allowed to calculate the absorption coefficient (alpha = 4pik/lamda) spectral dependencies and the spectra of light transmittance in layered barrier structures metal(Au)/fullerene/Si. Photoelectric properties of the films were investigated as well. The experimentally measured values of band gap were in a good agreement with mobility gap values (2.3 +/- 0.1 eV). The decoration of fullerene films (both pristine and chemically crosslinked) with silver nanoparticles did not change the photocurrent spectra as compared to those for undecorated fullerene films, but lowered the values of internal quantum efficiency Qint. The photocurrent generated in fullerene/Si heterostructure, showed a maximum value at lamda to appromimately 450 nm (Qint max approximately = 0.25 for decorated and undecorated C60-DA/Si films), and it was higher for the samples based on pristine C60 films, in accordance with their higher absorption coefficient. Diminishing of Qint for C60-DA/Si and C60-DA-Ag/Si films was observed for the spectral range of photocurrent generated in Si layer. The analysis of dark current-voltage characteristics showed that the barrier properties differ insignificantly, though a certain increase of series resistance was observed for the C60-DA/Si samples.

Valoración de las glucemias después de un ejercicio físico prolongado con la tecnología FreeStyle(R) en dedo y sitios alternativos / Paired blood glucose measurements from fingertip and alternative sites after prolonged physical exercise using the FreeStyleTM) technology

Introducción: La medición de la glucemia en los sitios alternativos al dedo ha sido posible gracias al desarrollo de sistemas de detección electroquímica, que permiten utilizar una microgota de sangre. Los estudios publicados al respecto se han realizado en la palma de la mano y el antebrazo sin tener en cuenta otros lugares. También se han llevado a cabo en relación con la ingesta y las dosis de insulina, pero no tras un ejercicio físico prolongado, dada la dificultad que supone. Objetivos: Averiguar si existen diferencias entre los pares de glucosa dedo/sitio alternativo después de un ejercicio prolongado. Conocer, entre los posibles, el sitio alternativo de punción preferido por los usuarios. Material y métodos: Se incluyeron en el estudio 15 personas con una media de edad de 33,87 ± 6,32 años, 11 con diabetes tipo 1 (DM1) de 11,67 ± 8,77 años de evolución, y 4 sin diabetes, que recorrieron el Camino de Santiago durante un periodo de ocho días. Se firmó el consentimiento informado para participar en la recogida de datos. Se realizaron cuatro jornadas caminando, dos en bicicleta, y ejercicios alternativos en días intercalados. Se registraron los pares glucemia en el dedo y en el sitio alternativo de libre elección en cada momento (n= 338). Todas las glucemias se midieron con la tecnología FreeStyle(R) (Abbott, Alameda, Estados Unidos). Los datos se analizaron con el programa SAS 9.1. Se calcularon los coeficientes de correlación intraclase aplicando la fórmula de Shrout-Fleiss (indica baja fiabilidad cuando el coeficiente es 0,75). Se efectuó una correlación entre las glucemias medidas en dedo y sitios alternativos usando la parrilla de error de Parkes. Resultados: El coeficiente de Shrout-Fleiss sitio alternativo frente a dedo fue 0,903. El coeficiente de los distintos tipos de ejercicio osciló entre 0,688 y 0,986, y el de los diferentes lugares alternativos de punción varió entre 0,663 y 0,823. La variable «no haber realizado ejercicio previamente» fue de 0,873. La correlación lineal dedo/sitio alternativo dio un coeficiente de correlación de 0,965 (p<0,0001). Según la parrilla de error de Parkes, el 100% de los puntos quedaron dentro de zonas de exactitud clínica A y B (92,3 y 7,7%, respectivamente), de modo que ninguno de ellos se situó en las zonas de inexactitud clínica (C, D o E). Los sitios alternativos utilizados con mayor frecuencia como zonas de punción fueron el antebrazo (44%), el muslo (23%) y la eminencia tenar (19%). Conclusiones: Los valores de glucemia de los sitios alternativos resultaron en este estudio similares a los obtenidos en el dedo, tanto en reposo como tras un ejercicio físico prolongado. Para este grupo, los lugares preferidos de punción alternativa fueron el antebrazo, la eminencia tenar y el muslo

Introduction: Blood glucose measurement at sites other than the fingertip has been made possible by the development of electrochemical devices, which require only a very small drop of blood. However, studies published on this topic refer only to testing blood from the palm or forearm, but not from alternative sites. Moreover, the studies took into account the timing of insulin administration and ingestion of food, but did not assess the effect of prolonged physical activity because of the difficulties involved. Objectives: To compare the affect of prolonged physical exercise on blood glucose measurements in samples taken from the fingertip with those taken from alternative sites. To determine which alternative site is preferred by users. Materials and methods: The study population consisted of 15 individuals aged 33.87 ± 6.32 years, 11 with type 1 diabetes mellitus, with a mean duration of diabetes of 11.67 ± 8.77 years, and 4 without diabetes. Signed informed consent was obtained prior to participation. They all undertook the Route of St. James to Santiago de Compostela in northern Spain over an 8-day period. The route was covered by walking for four days and by bicycle for two days, with other types of exercise on the remaining days. The subjects freely chose an alternative testing site (ATS) for each measurement, which was paired with the results in the sample from the fingertip (n= 338). Blood glucose was measured using the FreeStyle(TM) technology (Abbott, Alameda, CA, USA). Data were analyzed with the SAS 9.1 software package. Intraclass correlation coefficients were assessed by means of Shrout-Fleiss analysis (which indicates low reliability at a coefficient 0.75). The correlation between fingertip and ATS blood glucose results was calculated using the Parkes error grid. Results: The correlation coefficient for fingertip versus ATS according to Shrout-Fleiss analysis was 0.903. The coefficient for the different types of exercise ranged between 0.688 and 0.986, and for the different ATS, from 0.663 to 0.823. For the variable "no prior exercise", it was 0.873. The analysis of the linear correlation for finger versus ATS resulted in a correlation coefficient r= 0.965 (p<0.0001). Using Parkes error grid, 100% of the data plotted were within zones A and B (92.3% and 7.7%, respectively); thus, none of the measurements were in zones C, D or E. The preferred ATS sites were forearm (44% of total ATS), thigh (23%) and the base of the thumb (19%). Conclusions: In the present study, blood glucose values measured in samples from fingertip or ATS were found to be similar, both after rest and after prolonged physical exercise. The preferred ATS sites were forearm, thigh and the base of the thumb

Cross-linking of C60 films with 1,8-diaminooctane and further decoration with silver nanoparticles.

We applied the direct solvent-free functionalization of fullerene C60 with aliphatic bifunctional amine, 1,8-diaminooctane, to prepare chemically cross-linked C60 thin films capable of binding silver nanoparticles. The gas-phase diamine treatment of C60 reduced dramatically the fullerene solubility in toluene, indicating the transformation of pristine C60 into a different solid phase with cross-linked fullerene molecules. Compared to the spectra of pristine C60 film and powder samples, Fourier-transform infrared, UV-Visible, Raman, and 13C nucleic magnetic resonance spectra of the functionalization products exhibited new features, which point to a breaking of C60 ideal structure during the formation of new covalent bonds and to the appearance of sp3 hibridization. The covalent functionalization with 1,8-diaminooctane allowed for a stable and homogeneous deposition of silver nanoparticles of ca. 5-nm diameter onto the functionalized films through the coordination bonding between metal atoms and nitrogen donor atoms of the fullerene derivatives. The proposed mechanism of Ag nanoparticle binding was supported by density functional theory calculations using the hybrid BLYP functional in conjunction with the double numerical basis set DND.

[Correlation between clinical and autopsy diagnoses at a general hospital]. / Análisis de concordancia entre diagnósticos clínicos y de autopsia en un hospital general.

In the past years, the number of hospital clinical autopsies have significantly decreased, with the risk of loosing some of the functions of this procedure, among which the evaluation of the diagnostic accuracy, which has been considered as a health care quality index, stands out. In this paper, the consistency between clinical diagnosis and autopsies in a general hospital is studied, as well as its association to some potentially relevant factors. We review 91 autopsies performed in patients dying in the Service of Internal Medicine during a period of six years. Each case was classified though consensus among a clinician and a pathologist into: mayor clinicopathological discrepancy, minor discrepancy or complete consistency. The relationship between consistency and age, sex, average length of stay in the hospital and study period was analyzed. The 91 autopsies were performed on 64 men and 27 women. The mean age was 63 years and the average length of study in the hospital was 9.7 days. The global consistency was 71.4%. In 15 (16.5%) cases, a major discrepancy was observed and in 11 (12.1%), a minor discrepancy. No differences were observed in the degree of consistency with respect to age, sex, average length of stay and study period. Cardiovascular diseases showed the greatest proportion of major discrepancies at the expense of three cases of pulmonary thromboembolism. We conclude that the degree of concordance in this study is consistent with other studies and we discuss the relevance of clinical autopsies regarding several aspects of health care.