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Nicotianamine (NA) and 2'-deoxymugenic acid (DMA) are metal-chelating ligands that promote the accumulation of metals in rice endosperm, but it is unclear how these phytosiderophores regulate the levels of different metals and limit their accumulation. In this study, transgenic rice plants producing high levels of NA and DMA accumulated up to 4-fold more iron (Fe) and 2-fold more zinc (Zn) in the endosperm compared with wild-type plants. The distribution of Fe and Zn in vegetative tissues suggested that both metals are sequestered as a buffering mechanism to avoid overloading the seeds. The buffering mechanism involves the modulation of genes encoding metal transporters in the roots and aboveground vegetative tissues. As well as accumulating more Fe and Zn, the endosperm of the transgenic plants accumulated less cadmium (Cd), suggesting that higher levels of Fe and Zn competitively inhibit Cd accumulation. Our data show that although there is a strict upper limit for Fe (~22.5 µg g-1 dry weight) and Zn (~84 µg g-1 dry weight) accumulation in the endosperm, the careful selection of strategies to increase endosperm loading with essential minerals can also limit the accumulation of toxic metals such as Cd, thus further increasing the nutritional value of rice., (© The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.)

Reconstruction after large chest wall resections must ensure not only anatomical coverage but a normal respiratory function, specially in the case of associated ventilatory disturbance. Since prosthetic reconstruction can present some problems such as rejection, excessive rigidity or infection, bone grafts have been proposed as an alternative to synthetic materials, due to their effectiveness and capability of integration with host tissues. Although iliac bone allograft or autologous ribs harvested from the opposite operative side are described for reconstruction, we present here the first reported clinical case of donor cryopreserved rib allografts use after extensive chest wall resection in a patient with severe COPD, showing excellent short-term results in the absence of pulmonary function impairment.

We review our experience in the treatment of complex large chest-wall defects needing a multidisciplinary approach due to primary or secondary neoplasms. Non-small cell lung cancer with chest-wall invasion cases are excluded. Fifteen patients underwent whole thickness resection of the chest wall due to lesions affecting at least three ribs, sternum, clavicle or thoracic spine and the surrounding soft tissue. Previously operated breast cancer and sarcoma were the most frequent diagnoses. Partial or total sternectomy plus rib resection was performed in 8 patients. Immediate closure of the defects was performed in all cases: 12 with single prosthesis placement and 3 with a rigid one of methylmethacrylate. Coverage was achieved using myocutaneous flaps in most cases and, in one case, using the greater omentum that supported a free split-thickness skin graft. No 30-days mortality was recorded. Three patients had a post-operative complication. Mean hospital stay was 11.7+/-9 days. All cases of primary tumours were alive at the time of review (range: 6-126 months). In conclusion, resection and immediate reconstruction of large chest wall defects can be accomplished without operative mortality and low morbidity whenever close cooperation between plastic and thoracic teams exists.