Antimony distribution and mobility in different types of waste derived from the exploitation of stibnite ore deposits.

Wastes derived from the exploitation of stibnite ore deposits were studied to determine their mineralogical, chemical, and environmental characteristics and establish the Sb distribution and the current and long-term risks of Sb mobilization. Representative samples of mine waste rocks, mine tailings, and smelting waste were studied by X-ray powder diffraction, polarized light microscopy, electron microprobe analysis, and digestion, leaching, and extraction procedures. The main Sb-bearing minerals and phases identified in the smelting waste were natrojarosite, iron (oxyhydr)oxides, mixtures of iron and antimony (oxyhydr)oxides, and tripuhyite; those in the mine tailings and mine waste rocks were iron (oxyhydr)oxides and/or mixtures of iron and antimony (oxyhydr)oxides. Iron (oxyhydr)oxides and natrojarosite had high Sb contents, with maximum values of 16.51 and 9.63 wt% Sb2O5, respectively. All three types of waste were characterized as toxic; the mine waste rocks and mine tailings would require pretreatment to decrease their leachable Sb content before they would be acceptable at hazardous waste landfills. Relatively little of the Sb was in desorbable forms, which accounted for <0.01 and <0.8% of the total Sb content in the smelting waste and mine waste rocks/mine tailings, respectively. Under reducing conditions, further Sb mobilization from mine waste rocks and mine tailings could occur (up to 4.6 and 3.3% of the total content, respectively), considerably increasing the risk that Sb will be introduced into the surroundings. Although the smelting waste had the highest total Sb content, it showed the lowest risk of Sb release under different environmental conditions. The significant Fe levels in the smelting waste facilitated the formation of various Fe compounds that greatly decreased the Sb mobilization from these wastes.

Behaviour and survival of high-grade neuroendocrine carcinomas of the lung.

INTRODUCTION: Large-cell neuroendocrine carcinoma is an aggressive variant of large-cell carcinoma of the lung, which has poor survival in most series, resembling that of small-cell lung carcinoma. We report our retrospective assessment of surgically-resected cases of both tumours. METHODS: 33 large-cell neuroendocrine carcinomas and 16 peripheral small-cell lung carcinomas were reassessed retrospectively. Survival rates of both tumours in surgically-resected cases were calculated and compared using Kaplan-Meier survival curves and Log Rank test, respectively. RESULTS: In large-cell neuroendocrine carcinomas, there were 25 patients with pathologic stage I, 4 with pathologic stage II and 4 with pathologic stage III. In small-cell lung carcinomas, there were 6 patients with pathologic stage I, 3 with pathologic stage II and 7 with pathologic stage III. 12% of large-cell neuroendocrine carcinomas and 62.5% of small-cell lung carcinomas were of advanced disease. The mean follow-up was 89 months. The actuarial survival for the 2 groups was not significantly different. CONCLUSION: Large-cell neuroendocrine carcinomas of the lung have poor prognosis even in early stages, with survival rates similar to that of small-cell lung carcinomas.

Toracotomía urgente en traumatismos penetrantes y cerrados: incidencia, características demográficas y análisis de resultados en un registro hospitalario de traumatizados graves / Urgent thoracotomy in blunt and penetrating trauma: incidence, demographic characteristics and analysis of results in a hospital registry of severe trauma

Objetivo. En países de nuestro entorno europeo la necesidad de toracotomía urgente por traumatismo es escasa. Nuestro objetivo ha sido analizar la gravedad de los pacientes con traumatismo penetrante (TP) y cerrado (TC) que han necesitado toracotomía urgente, con el fin de valorar si la toracotomía por traumatismo en nuestro medio no conlleva peores resultados, en términos de supervivencia, que el estándar internacional. Métodos. Hemos analizado las características demográficas, indicaciones, tipos, escalas de gravedad (RTS, AIS, ISS y NISS) y TPS (TRISS Probability of Survival), así como las muertes potencialmente evitables y posibles errores de manejo inicial de los pacientes traumatizados que han necesitado una toracotomía dentro de las primeras 48 h. Resultados. Entre agosto de 1993 y agosto de 2002 se ha recogido en nuestro registro de traumatizados graves un abordaje torácico urgente, único o combinado con otras vía de abordaje, en 51 pacientes. En 26 y 25 pacientes la toracotomía fue por TP y TC, respectivamente. En el grupo con TP el tiempo medio de transporte fue de 49 min. Las indicaciones del abordaje torácico fueron: 3 casos por situación in extremis en el Departamento de Urgencias, 11 por shock al ingreso, 10 por lesiones específicas en pacientes que no estaban en shock y 2 por hemorragia persistente a través de un tubo de drenaje. Un 11,5 por ciento necesitaron abordaje toracoabdominal combinado. La lesión más frecuente fue la herida por arma blanca cardíaca AIS V. El RTS, ISS y NISS medios fueron de 8,2, 23 y 30, respectivamente. La mortalidad a 30 días fue de 7 casos (27 por ciento). En función del TPS dos de los fallecidos aparecen como muertes potencialmente evitables. En el grupo con TC el tiempo medio de transporte fue de 63 min. Las indicaciones de la toracotomía fueron: 3 casos por situación in extremis, 3 por shock al ingreso, 14 por lesiones especificas en pacientes que no estaban en shock y 5 por hemorragia torácica persistente. Un 32 por ciento necesitaron un abordaje toracoabdominal combinado. Hubo lesiones cardíacas o de grandes vasos en 11 pacientes (44 por ciento). El RTS, ISS y NISS medios fueron de 8,9, 34 y 41, respectivamente. La mortalidad a los 30 días fue de 12 casos (48 por ciento), y 2 aparecen como muertes potencialmente evitables en función del TPS. Conclusiones. En las toracotomías por TP los "tiempos de transporte" parecen prolongados a la luz de las recomendaciones de la bibliografía. La necesidad de reanimación cardiopulmonar (RCP) avanzada in situ o durante el traslado ha sido un factor de pronóstico fatal en nuestra serie. En el TC una causa muy frecuente de toracotomía urgente ha sido la rotura aórtica y de cavidades cardíacas. La necesidad de laparotomía asociada ha sido frecuente, y conlleva una alta mortalidad. La baja incidencia global de toracotomía urgente por traumatismo en nuestro medio no parece influir negativamente en los resultados de supervivencia, aunque se han detectado errores de evaluación y manejo susceptibles de corrección (AU)

[Thymectomy in myasthenia gravis]. / Timectomía en la miastenia gravis.

OBJECTIVE: To analyze outcome after thymectomy in patients with myasthenia gravis (MG). MATERIAL AND METHODS: Thirty-five patients with MG underwent surgery in our service between June 1987 and June 1998. Ten had associated thymomas. Preoperative Osserman classification showed 2 at level I, 20 at level IIA, 11 at level IIB and 2 at level III. Extended thymectomy through a medial sternotomy was performed in all. RESULTS: Postoperative complications developed in three patients (1 medullary aplasia, 1 postoperative reintubation, 1 myasthenic crisis). Mean follow-up was 89 months, with 22.8% achieving complete remission and 97.1% reporting improvements. The results were similar in the 10 patients with thymomas (20% full remission and 90% showing improvement). By DeFilippi classification, 22.8% were in class 1, 22.8% in class 2, 51.4% in class 3 and 2.8% in class 4. By Osserman classification, 9 were in the same category before and after surgery, 12 had improved one level, 10 had improved 2 levels, 3 had improved 3 levels and 1 patient had improved 4 levels. CONCLUSION: Thymectomy is an appropriate therapeutic procedure in the multidisciplinary treatment of patients with MG and it is the approach of choice for patients with associated thymomas. The intra- and post-operative complication rate is low and the rate of clinical improvement is high.