Whole breast proton irradiation for maximal reduction of heart dose in breast cancer patients

PURPOSE: In left-sided breast cancer radiotherapy, tangential intensity modulated radiotherapy combined with breath-hold enables a dose reduction to the heart and left anterior descending (LAD) coronary artery. Aim of this study was to investigate the added value of intensity modulated proton therapy (IMPT) with regard to decreasing the radiation dose to these structures. METHODS: In this comparative planning study, four treatment plans were generated in 20 patients: an IMPT plan and a tangential IMRT plan, both with breath-hold and free-breathing. At least 97 % of the target volume had to be covered by at least 95 % of the prescribed dose in all cases. Specifically with respect to the heart, the LAD, and the target volumes, we analyzed the maximum doses, the mean doses, and the volumes receiving 5-30 Gy. RESULTS: As compared to IMRT, IMPT resulted in significant dose reductions to the heart and LAD-region even without breath-hold. In the majority of the IMPT cases, a reduction to almost zero to the heart and LAD-region was obtained. IMPT treatment plans yielded the lowest dose to the lungs. CONCLUSIONS: With IMPT the dose to the heart and LAD-region could be significantly decreased compared to tangential IMRT with breath-hold. The clinical relevance should be assessed individually based on the baseline risk of cardiac complications in combination with the dose to organs at risk. However, as IMPT for breast cancer is currently not widely available, IMPT should be reserved for patients remaining at high risk for major coronary events

Aplicação de água salina no desenvolvimento e comportamento fisiológico do coqueiro Application of saline water in the development and physiological behavior of the coconut

Avaliou-se o efeito do déficit hídrico e da irrigação com água de diferentes níveis de salinidade, no desenvolvimento do coqueiro (Cocos nucifera L.) "Gigante do Brasil", com cinco anos de idade e cultivado em condições de campo. O experimento foi conduzido no Campo Experimental da Embrapa Tabuleiros Costeiros, localizado no município de Itaporanga D'Ajuda, SE. O delineamento experimental utilizado foi em blocos ao acaso, com quatro tratamentos e quatro repetições. Cada parcela foi constituída de 12 plantas úteis. Os tratamentos foram: plantas sem irrigação (T0), aplicação de 40 L de água doce por planta em intervalos de 3 dias (T1), aplicação de água contendo 7,5 e 15,0 g L-1 de sais totais (T2 e T3). Analisaram-se as seguintes variáveis: número de folhas vivas, número de folhas mortas, porcentagem de plantas vivas no final do experimento, potencial hídrico foliar e condutância estomática. A análise dos dados demonstrou que os tratamentos T0 e T3 diferiram significativamente quanto ao número de folhas vivas, mas a variável condutância estomática no período seco foi afetada em todos os tratamentos, o que mostrou a insuficiência da quantidade de água aplicada. No final do experimento, a percentagem de sobrevivência foi de 83% para T1, 81% para T2, 79% para T3 e 58% para T0. Conclui-se, então, que a irrigação com água contendo até 15 g L-1 de sais em períodos de seca transitória, é essencial para evitar a perda de plantas jovens do coqueiro "Gigante do Brasil", no Nordeste do Brasil.<br>This work was carried out with the objective of evaluating the effect of the drought and the application of water of different levels of salinity in the development of five years old "Brazilian Tall" coconut (Cocos nucifera L.) cultivated under field conditions. The experiment was conducted at the Itaporanga Experimental Station in the State of Sergipe located in Northeast of Brazil. The experimental design consisted of randomized blocks (4) with 4 treatments and each repetition constituted of 12 plants. The applied treatments were: T0 - not irrigated; T1 - application of 40 L per plant of fresh water at intervals of 3 days; T2 and T3 - application of saline water containing 7.5 and 15.0 g L-1 of total salts. The following variables were analyzed: number of living leaves, number of dead leaves, the percentage survival of plants at the end of the experiment, the leaf water potential and the stomatal conductance. The analysis of the data showed that the treatments T0 and T3 affected significantly the number of living leaves, but the variable stomatal conductance in the dry period was affected by all the treatments, which points out the inadequacy of the amount of water applied. At the end of the experiment, the survival percentage was of 83% for T1, 81% for T2, 79% for T3 and 58% for T0. The results permit to conclude that water containing up to 15 g L-1 salts during dry season is essential to avoid the loss of young plants

Subcellular targeting strategies for drug design and delivery

Many drug targets are localized to particular subcellular compartments, yet current drug design strategies are focused on bioavailability and tissue targeting and rarely address drug delivery to specific intracellular compartments. Insights into how the cell traffics its constituents to these different cellular locations could improve drug design. In this Review, we explore the fundamentals of membrane trafficking and subcellular organization, as well as strategies used by pathogens to appropriate these mechanisms and the implications for drug design and delivery