We analyzed antioxidative defenses, photosynthesis, and pigments (especially xanthophyll-cycle components) in two wheat (Triticum durum Desf.) cultivars, Adamello and Ofanto, during dehydration and rehydration to determine the difference in their sensitivities to drought and to elucidate the role of different protective mechanisms against oxidative stress. Drought caused a more pronounced inhibition in growth and photosynthetic rates in the more sensitive cv Adamello compared with the relatively tolerant cv Ofanto. During dehydration the glutathione content decreased in both wheat cultivars, but only cv Adamello showed a significant increase in glutathione reductase and hydrogen peroxideglutathione peroxidase activities. The activation states of two sulfhydryl-containing chloroplast enzymes, NADP ؉ -dependent glyceraldehyde-3-phosphate dehydrogenase and fructose-1,6-bisphosphatase, were maintained at control levels during dehydration and rehydration in both cultivars. This indicates that the defense systems involved are efficient in the protection of sulfhydryl groups against oxidation. Drought did not cause significant effects on lipid peroxidation. Upon dehydration, a decline in chlorophyll a, lutein, neoxanthin, and ␤-carotene contents, and an increase in the pool of de-epoxidized xanthophyll-cycle components (i.e. zeaxanthin and antheraxanthin), were evident only in cv Adamello. Accordingly, after exposure to drought, cv Adamello showed a larger reduction in the actual photosystem II photochemical efficiency and a higher increase in nonradiative energy dissipation than cv Ofanto. Although differences in zeaxanthin content were not sufficient to explain the difference in drought tolerance between the two cultivars, zeaxanthin formation may be relevant in avoiding irreversible damage to photosystem II in the more sensitive cultivar.

The recently described telomerase reverse transcriptase (TERT) promoter mutations are recurrent in cutaneous melanoma. Several authors have described an association between these molecular alterations, some histological parameters, and patient survival. BRAF mutations are very frequent in melanoma, but their actual role in the evolution of the disease is still unclear. Here, we investigated the relationship of TERT promoter mutations and BRAF mutations with the most relevant clinicopathological parameters, individually and coexisting, in order to evaluate their role as independent prognostic markers and to determine the effect of their coexistence. A TERT promoter alteration was found in 20 of 53 cases (38 %), significantly associated with histological type, increasing tumor thickness and mitotic rate, more advanced pathologic tumor (pT) stage, and absence of regression. A BRAF mutation was found in 21 of 53 cases (40 %), significantly associated with tumor thickness and presence of metastases in the sentinel lymph node. Coexistence of a TERT promoter and BRAF mutation was detected in 11 of 53 cases (21 %). This was associated with increasing thickness, high mitotic rate, lymph node metastasis, presence of ulceration, and absence of regression. Coexistence of a mutation in the TERT promoter and in the BRAF gene correlated with more prognostically relevant factors than either mutation alone. Our data lead us to hypothesize that TERT promoter and BRAF mutations cooperate in cutaneous melanoma. Further studies in larger cohorts of patients are needed to investigate how this synergistic effect is involved in the evolution of the disease.

In patients with Leydig cell tumors testis sparing surgery with frozen section examination provides an excellent long-term oncological outcome.

No abstract

No abstract