Spanish multicenter study of surgical resection of pancreatic tumors infiltrating the celiac axis: does the type of pancreatectomy affect results?

Background Pancreatectomy plus celiac axis resection (CAR) is performed in patients with locally advanced pancreatic cancer. The morbidity rates are high, and no survival benefit has been confirmed. It is not known at present whether it is the type of pancreatectomy, or CAR itself, that is the reason for the high complication rates. Methods Observational retrospective multicenter study. Inclusion criteria: patient undergoing TP, PD or DP plus CAR for a pancreatic cancer. Results Sixty-two patients who had undergone pancreatic cancer surgery (PD,TP or DP) plus CAR were studied. Group 1: 17 patients who underwent PD/TP-CAR (13TP/4PD); group 2: 45 patients who underwent DP-CAR. Groups were mostly homogeneous. Operating time was longer in the PD/TP group, while operative complications did not differ statistically in the two groups. The number of lymph nodes removed was higher in the PD/TP group (26.5 vs 17.3), and this group also had a higher positive node ratio (17.9% vs 7.6%). There were no statistical differences in total or disease-free survival between the two groups. Conclusion It seems that CAR, and not the type of pancreatectomy, influences morbidity and mortality in this type of surgery. International multicenter studies with larger numbers of patients are now needed to validate the data presented here (AU)

In silico analysis of phytohormone metabolism and communication pathways in citrus transcriptome

Plant hormones play a crucial role in integrating endogenous and exogenous signals and in determining developmental responses to form the plant body throughout its life cycle. In citrus species, several economically important processes are controlled by phytohormones, including seed germination, secondary growth, fruit abscission and ripening. Integrative genomics is a powerful tool for linking newly researched organisms, such as tropical woody species, to functional studies already carried out on established model organisms. Based on gene orthology analyses and expression patterns, we searched the Citrus Genome Sequencing Consortium (CitEST) database for Expressed Sequence Tags (EST) consensus sequences sharing similarity to known components of hormone metabolism and signaling pathways in model species. More than 600 homologs of functionally characterized hormone metabolism and signal transduction members from model species were identified in citrus, allowing us to propose a framework for phytohormone signaling mechanisms in citrus. A number of components from hormone-related metabolic pathways were absent in citrus, suggesting the presence of distinct metabolic pathways. Our results demonstrated the power of comparative genomics between model systems and economically important crop species to elucidate several aspects of plant physiology and metabolism.

Identifying water stress-response mechanisms in citrus by in silico transcriptome analysis

Water deficit is one of the most critical environmental stresses to which plants are submitted during their life cycle. The evolutionary and economic performance of the plant is affected directly by reducing its survival in the natural environment and its productivity in agriculture. Plants respond to water stress with biochemical and physiological modifications that may be involved in tolerance or adaptation mechanisms. A great number of genes have been identified as transcriptionally regulated for water deficit. EST sequencing projects provide a significant contribution to the discovery of expressed genes. The identification and determination of gene expression patterns is important not only to understand the molecular bases of plant responses but also to improve water stress tolerance. In our citrus transcriptome survey we have attempted to identify homologs to genes known to be induced and regulated under water stress conditions. We have identified 89 transcripts whose deduced amino acid sequences share similarities with proteins involved in uptake and transport of water and ion, 34 similar to components of the osmolyte metabolism, 67 involved in processes of membranes and proteins protection and 115 homologs of reactive oxygen species scavenger. Many drought-inducible genes identified are known to be regulated by development, salt, osmotic and low temperature. Their possible roles in specific or general mechanisms of water stress citrus responses are discussed.

Estratégia quirúrgica en el carcinoma de células renales con extensión a la circulación venosa / Surgical stratification of renal carcinoma with extension into inferior vena cava

El carcinoma de células renales con trombo en vena cava inferior es una patología relativamente rara, que complica la nefrectomía radical. Durante los pasados veinte años nuestro hospital ha contribuido sustancialmente a la estratificación quirúrgica del carcinoma de células renales con extensión a la vena cava a través de diferentes técnicas. El objetivo de este artículo es describir las diferentes estrategias quirúrgicas necesarias y más apropiadas para el tratamiento de los distintos niveles del trombo tumoral. Consideramos que el diagnóstico de la invasión de la vena cava por el tumor y el nivel de extensión tumoral están basados en exámenes radiológicos, los cuales son determinantes a la hora del planteamiento quirúrgico y éxito de la cirugía. Somos partidarios del uso de filtros de vena cava colocados. Preoperatoriamente para prevenir el riesgo de tromboembolismos pulmonares durante y después de la cirugía. El uso de prótesis de cava es excepcional, debido a que la obstrucción crónica producida por el trombo tumoral, permitirá el desarrollo de una extensa circulación colateral que actuará como un bypass veno-venoso. Por último, intentamos evitar el uso de bypass veno-venoso o bypass cardiopulmonar con o sin hipotermia y parada cardiocirculatoria, debido a la alta morbimortalidad que conllevan (AU)

Renal cell carcinoma with inferior vena cava thrombus is relatively uncommon and complicates radical nefrectomy. During the past twenty years our hospital have substantially contributed to the surgical stratification of renal cell carcinoma with extension into inferior vena cava through different techniques. The reason; for this article is to discuss the more efficient and appropiate surgical technique for this pathology. We believe that the diagnosis of vena caval invasion and level of tumoral extension is based on radiological examinations and it is crucial for the success of the surgery. We consider that the use of vena caval filter applied preoperatively could prevent the risk of thromboembolism during and after the surgery. The use of prosthetic; grafts is unusual, because the long standing obstruction caused by the tumor thrombus will develope extensive collateral circulation which works as a natural veno-venous bypass. Finally, we try to avoid the use of veno-venous and cardiopulmonar bypass with or without complete hypothermic circulatory arrest due to the high association with adverse outcomes and mortality (AU)

Actividad de un programa de trasplante intestinal pediátrico en España* / Activity of a pediatric intestinal translantation program in Spain

Objetivos. 1°. Analizar la evolución de los niños con fallo intestinal (FI) valorados y aceptados como candidatos a trasplante intestinal (TI). 2°. Discutir estrategias para evitar la mortalidad pretrasplante en lista de espera de los niños candidatos al procedimiento. Material y métodos. Desde julio de 1997 se han evaluado 23 niños con FI como potenciales candidatos a TI; ocho fueron incluidos en lista para trasplante y constituyen el material de este estudio. Las causas de FI fueron síndrome de intestino corto (SIC) en seis, y enfermedad de inclusión a microvilli (EIM) en dos. El FI se asoció en cinco niños a enfermedad hepática terminal y fueron incluidos, por tanto, para trasplante combinado de hígado-intestino (THI); los tres restantes fueron incluidos para trasplante de intestino aislado (TIA), indicado por pérdida de accesos venosos profundos en uno; y por fibrosis hepática progresiva en dos, con el objeto de evitar posteriormente un eventual THI; uno de ellos asociaba además pérdida importante de acceos venosos profundos. Al incluirse en lista de trasplante, la media de edad y peso fue de 11 meses y 8,1 kg, respectivamente (rangos de 4 meses-25 meses y 4 kg-16 kg, respectivamente), Resultados. Dos niños candidatos ambos a THI fallecieron sin poderse trasplantar, tras un tiempo en lista de espera para trasplante de 5 y 14 meses, respectivamente. Cuatro están actualmente activos en lista, dos para THI y dos para TIA; el tiempo de espera oscila entre 2 y 10 meses. Otros dos han sido trasplantados, uno con TIA en un caso de displasia microvellositaria (variante de la EIM) y otro con THI en una niña con SIC asociado a cirrosis; el tiempo de evolución postrasplante es de 18 y 8 meses, respectivamente. Tras el TI, ambos consiguieron una autonomía digestiva completa, quedando libres de NP. Conclusiones. El tiempo de espera en lista de los niños candidatos a TI es prolongado, y se debe a la escasez de donantes adecuados. Dos estrategias permiten disminuir la mortalidad pretrasplante: 1ª. Referencia precoz del niño con FI a un centro en donde se ofrezca la posibilidad de TI. 2ª. Aplicación de técnicas quirúrgicas que permiten usar donantes de peso varias veces superior al del receptor (utilizadas en nuestro caso de THI y discutidas en la comunicación) y que incrementan, por tanto, las posibilidades de acceso al trasplante (AU)