Persistent Bactericidal Action by a Silver Disinfectant on Surfaces of Hospital Furniture.

Aims: In hospitals, surfaces are often colonized by potentially pathogenic micro organisms which can remain alive for long periods of time, thus playing a major role in hospitalacquired infections. One way to overcome this drawback could be to use disinfectants with long-term action. Recent studies have shown that not only do disinfectants containing silver present an immediate effect, reducing the surface bacterial load, but that this action also appears persistent in time. This work assesses the bactericidal activity of a long-lasting disinfectant complex composed of silicon oxide, silver ions and a cationic surfactant (BACTERCLINE ENERGY BLAST) applied on the surfaces of two surgery ward rooms and left in place for different amounts of time (15 min and 72 hours). Study Design: An experimental study. Place and Duration of Study: The investigation was carried out in two rooms of a surgical ward at the Villa Erbosa health care facility in Bologna (Italy) over a period of seven weeks. Methodology: The samples were taken using contact plates (diameter: 24 cm2) containing an adequate agar culture medium (Tryptic Soy Agar). After incubation at the temperature of 36±1ºC for 24 and 48h, the number of colonies was counted and the statistical analysis of results was performed. Results: The product was able to achieve a high degree of decontamination (around 90%) immediately after application and that, after 72 hours, decontamination remained at about 55%. The results are statistically significant. Conclusion: It may be concluded that the tested product could be profitably used to decontaminate surfaces in hospital wards.

Estudio genetico demografico del Estado Zulia, Venezuela, a traves de isonimia / Genetic demographic study of the Zulia State, Venezuela, by isonymy

Se estudió la estructura genética del Estado Zulia, Venezuela, a través de la distribución de los apellidos de individuos mayores de 40 años, inscritos en el registro electoral. La muestra analizada fué de 440.190 individuos, que compartían un total de 10.423 apellidos diferentes. Para cada uno de las 81 parroquias del Estado se estimó el porcentaje de la población incluída en los apellidos únicos (estimador A), el porcentaje de la población incluída en los siete apellidos más frecuentes (estimador B), el coeficiente de parentesco debido a isonimia al azar phiii y el ni de Karlin y McGregor (v), un indicador de migración La correlación entre B y (phiii) fué de 0,92, indicando que 85 por ciento de la variación observada en el coeficiente de parentesco por isonimia al azar se debe a los siete apellidos más frecuentes. El estimador A y el ni de Karlin y McGregor muestran una correlación de 0,93, de modo que 86 por ciento de la variación observada en v se debe a los apellidos que aparecen una sola vez. Por otra parte, la correlación entre phiii y v, y aquella entre A y B fueron no significativas (-0,08 y -0,17 respectivamente), indicando que estos estimadores están midiendo aspectos diferentes de estructura poblacional: phiii y B aislamiento, mientras que v y A miden migración. Las parroquias más aisladas del Zulia tienden a ubicarse hacia el noroccidente, dentro de la Guajira venezolana, aunque tambien se observa cierto aislamiento hacia el sur del Lago de Maracaibo. El aislamiento por distancia dentro de este Estado de manifesta con una correlación entre distancia geográfica y distancia euclideana igual a 0,63. Este valor tan elevado puede deberse, en parte, al efecto de barrera geográfica que ejerce el lago. Se identificaron 8 apellidos con distribución focal, es decir, frecuencia mayor de 4 por ciento en una sola parroquia, y menor de 0,5 por ciento en más de 90 por ciento de las restantes: Almarza, badell, Bastidas, Bohórquez, Cardozo, Carmona, Espina y Matos. Los portadores de estos apellidos tienen una alta probabilidad de provenir de las parroquias donde están focalizados.

Estructura genética poblacional del Estado Guárico, Venezuela, estimada a través de isonimia / Genetic structure of the population of Guarico, Venezuela, studied through isonymy

The genetic structure of the State of Guárico, Venezuela, was studied through the distribution of surnames from individuals above 40 years of age, obtained from the register of electors. The sample studied consisted in 109,200 individuals and 14,138 different surnames. For each of the 32 counties of the State, the following estimators were calculated: percentage of the population included in surnames which appear only once (estimator A), percentage of the population included in the seven most frequent surnames (estimator B), the coefficient of consanguinity due to random isonymy (n phi ii), and Karlin and McGregors ni nu, an estimator of migration. The correlation between n phi ii and B was 0.97, indicating that 94 percent of the variation observed in the coefficient of consanguinity due to random isonymy is due to the seven most frequent surnames. The correlation between A and ni was 0.93, so that 86 percent of the variation observed in ni, is due to surnames which appear only once. On the other hand, correlations between A and B, and between n phi ii and nu were non significant (0.25 and 0.01 respectively), meaning that they are measuring different features of population structure: B and n phi ii, and v were non significant (0.25 and 0.01 respectively), meaning that they are measuring different features of population structure: B and n phi ii, isolation, and A and nu, migration. The most isolated counties of Guárico, according to n phi ii and B, are Santa Rita, Espino, El Calvario, Ortiz and Santa María de Ipire. Microdifferentiation of the State was studied through the estimation of RST, which gave a value of 0.0008. Comparing this value with those obtained in other Venezuelan States, it is found that Guárico, with Aragua and Yaracuy, are among the least differentiated States, probably because of the absence of important geographical barriers and the nearness to the Capital City of our country