Rat subcutaneous tissue response to calcium silicate containing different arsenic concentrations

Objective: To evaluate the response of rat subcutaneous tissue in implanted polyethylene tubes that were filled with GMTA Angelus and Portland cements containing different arsenic concentrations. Material and Methods: Atomic absorption spectrophotometry was utilized to obtain the values of the arsenic concentration in the materials. Thirty-six rats were divided into 3 groups of 12 animals for each experimental period. Each animal received two implants of polyethylene tubes filled with different test cements and the lateral of the tubes was used as a control group. After 15, 30 and 60 days of implantation, the animals were killed and the specimens were prepared for descriptive and morphometric analysis considering: inflammatory cells, collagen fibers, fibroblasts, blood vessels and other components. The results were analyzed utilizing the Kuskal-Wallis test and the Dunn's Multiple test for comparison (p<0.05). Results: The materials showed, according to atomic absorption spectrophotometry, the following doses of arsenic: GMTA Angelus: 5.01 mg/kg, WPC Irajazinho: 0.69 mg/kg, GPC Minetti: 18.46 mg/kg and GPC Votoran: 10.76 mg/kg. In a 60-day periods, all specimens displayed a neoformation of connective tissue with a structure of fibrocellular aspect (capsule). Control groups and MTA Angelus produced the lower amount of inflammatory reaction and GPC Minetti, the highest reaction. Conclusions: There was no direct relationship between the concentration of arsenic present in the composition of the materials and the intensity of the inflammatory reactions. Higher values, as 18.46 mg/kg of arsenic in the cement, produce characteristics of severe inflammation reaction at the 60-day period. The best results were found in MTA angelus. .

Efecto en la estructura histológica del timo de ratas Sprague-Dawley tratadas con trióxido de arsénico / Effect on the histological structure of thymus on Sprague-Dawley treated with arsenic trioxide

En las áreas costeras del norte de Chile es común encontrar en el agua para consumo humano niveles medios o altos de arsénico. La exposición al arsénico puede ir asociada a efectos agudos o crónicos. El objetivo de esta investigación fue determinar el daño histológico que provoca el trióxido de arsénico a nivel de los compartimentos del timo de ratas Sprague-Dawley. Se utilizaron 24 ratas de ambos sexos de 55 días de vida. Las ratas fueron pesadas y divididas en 3 grupos (4 hembras y 4 machos). A los grupos tratados se les aplicó 5 mg y 10 mg de As2O3 respectivamente, en dosis única diaria vía intraperitoneal por 15 días. Al grupo control se le aplicó agua destilada sin arsénico. Después del tratamiento los animales fueron sacrificados y retirado el timo de ellos, los cuales fueron lavados, pesados y seccionados en dos, luego se fijaron en formol tamponado al 10 por ciento. Mediante técnica histológica convencional se obtuvieron 4 muestras seriadas de cada timo, de 5 um de espesor y separadas por 100 um entre si, luego fueron teñidas con H-E. Se analizaron 30 campos (120 campos por órgano). Los resultados muestran que el As2O3 provoca la pérdida de celularidad en ambos compartimentos del timo, tanto en la corteza como en la médula, viéndose más afectado el compartimento medular (junto a la unión corticomedular). Se observó una reducción significativa del tamaño de la zona medular en ambos grupos tratados (5 y 10 mg de As2O3 respectivamente), siendo probablemente la disminución de este tejido el responsable de la atrofia del timo. Además se observó un aumento del tamaño de la corteza en las ratas hembras tratadas con 10 mg de As2O3. La unión corticomedular de las ratas tratadas se observó difusa o difícil de distinguir.

In coastal areas of northern Chile medium or high levels of arsenic are commonly found in drinking water. Arsenic exposure may be associated with acute or chronic effects. The objective of this investigation was to determine the histological damage caused by arsenic trioxide level of the compartments of the thymus of Sprague-Dawley rats. We used 24 rats of both sexes of 55 days of life. The rats were weighed and divided into 3 groups (4 females and 4 males). In the treated groups were administered 5 mg and 10 mg of As2O3 respectively, in a single daily dose for 15 days intraperitoneally. The control group was administered distilled water without arsenic. After treatment the animals were sacrificed and the thymus removed, washed, weighed and divided into two, then fixed in 10 percent buffered formalin. By conventional histology samples were obtained serially every 4 thymus, 5 microns thick and separated by 100 microns each, then were stained with HE. We analyzed 30 fields (120 fields per organ). The results showed that As2O3 causes loss of cellularity in both compartments of the thymus, both in the cortex and in the bone, medullary compartment was more affected (near the corticomedullary junction). There was a significant reduction in the size of the medulla in both groups (5 and 10 mg As2O3 respectively), probably the decrease of the tissue responsible for thymic atrophy. We observed an increase in the size of the cortex in female rats treated with 10 mg of As2O3. The corticomedullary junction of the treated rats showed diffuse or difficult to distinguish.

La muerte de Napoleón: ¿causa natural u homicidio?

Napoleón Bonaparte murió a la edad de 52 años mientras purgaba exilio en la isla de Santa Helena, en el Atlántico Sur, una colonia británica donde fue desterrado luego de su derrota en Waterloo en 1815. Desde 1961 han abundado las teorías de que Napoleón murió envenenado con arsénico, particularmente porque el análisis de sus cabellos mostró elevados niveles del elemento tóxico. Sin embargo, de acuerdo a una nueva investigación sobre la causa de muerte del emperador francés, su muerte tuvo origen en una causa más prosaica de lo que muchos pensarían, sucumbió a un cáncer del estómago más que por envenenamiento arsenical. La autopsia describe un tumor gástrico de 10 cm de extensión. Otras fuentes históricas muestran que el obeso líder francés había perdido cerca de nueve kilogramos de peso en los últimos meses de su vida, otro signo de cáncer gástrico. La cavidad gástrica estaba llena de un líquido en borra de café, un claro signo de importante sangrado en el tracto digestivo. Este sangrado masivo, fue la causa inmediata de su muerte

Napoleon Bonaparte died at age 52 while in exile on the South Atlantic island of Saint Helena, a british colony, where he was banished after his defeat at the battle of Waterloo in 1815. Theories that Napoleon was poisoned with arsenic have abounded since 1961, when an analysis of his hair showed elevated levels of the toxic element. According to new research into what killed the french emperor his death’ cause was more prosaic than some people would like to think, succumbing to stomach cancer rather than arsenic poisoning, The autopsy describes a tumor in his stomach that was 4 inches (10 centimeters) long. Other historical sources indicate that the rotund French leader had lost about 20 pounds (nine kilograms) in the last few months of his life, another sign of stomach cancer. His stomach also contained a dark material similar to coffee grounds, a telltale sign of extensive bleeding in the digestive tract. The massive bleeding was likely the immediate cause of death