In this work, we compared nitrate-supplied plants (non-nodulated) with non-nitratesupplied plants (nodulated) under oxygen privation of root system (hypoxia) and re-oxygenation (post-hypoxia; recovery) in order to verify whether N sources affect the antioxidant system during oxidative stress caused by hypoxia and post-hypoxia conditions. Antioxidant enzymatic activities, ascorbate redox state, and reactive oxygen species (ROS) levels were analyzed in roots and leaves of two soybean genotypes, Fundacep 53 RR and BRS Macota at reproductive stage R2, during hypoxia and post-hypoxia in an experiment carried out in a hydroponic system. The antioxidant system was strongly induced in roots of nitrate-supplied plants of both genotypes, with high activity of superoxide dismutase, ascorbate peroxidase, catalase, glutathione reductase and guayacol peroxidase. It also increased reduced ascorbate and ascorbate redox state and decreased ROS production under hypoxia and recovery, while in leaves of nodulated and non-nodulated plants, a slight increase on antioxidant system was observed. Nitrate may benefit soybean plants under hypoxic conditions and subsequent re-oxygenation by inducing the antioxidant system mainly in roots to cope with ROS production and reduce oxidative damage.

Cereus hildmannianus K. Schum is a columnar cactus native to South and Southeast Brazil. The cultivation of this species seems justifiable for several reasons: its fruits are spineless and edible; it is not threatened with extinction; it naturally occurs in Pampa and Atlantic Forest under non-xeric conditions that may be unsuitable for the cultivation of other tropical cacti; and the plants are pollinator-dependent and so should benefit from native pollinators. This study aimed to test seed germination of C. hildmannianus with samples collected at three different localities in southern Brazil, as a necessary step preceding any attempts of management and domestication. Seeds were exposed to temperatures of 20° C, 25° C, 30° C and room temperature. The germinability, average germination time and synchronization index were calculated. All samples showed higher germinability at 20° C and 25° C. Seeds from Caçapava do Sul and Santiago showed significant variation in the synchronization index at 25° C and 30° C, respectively. Seeds from Porto Alegre had maximum germinability, indicating greater vigor. Our results show that the seeds of C. hildmannianus germinate well and thrive within a wide range of temperatures and that cultivation of the species from seed-raised plants should not be problematic.

Brazil is one of the centers of diversity of Cactaceae, yet studies addressing both pollination biology and the breeding system in Brazilian cacti are scarce. We herein present a detailed analysis of two native species with economic relevance: Cereus hildmannianus and Pereskia aculeata. The first species produce edible, sweet, spineless fruits and the second species produces leaves with high protein content. Pollination studies were undertaken through fieldwork observations in three localities of Rio Grande do Sul, Brazil, over two flowering seasons, totaling over 130 observation hours. Breeding systems were elucidated utilizing controlled pollinations. Cereus hildmannianus is solely pollinated by nectar-gathering species of Sphingidae hawk moths. In contrast, the flowers of P. aculeata are pollinated by predominantly native Hymenoptera but also by Coleoptera and Diptera, which gather pollen and/or nectar. Both cacti species are pollinator-dependent; neither intact nor emasculated flowers turn into fruit, yet whereas C. hildmannianus is self-incompatible, P. aculeata is fully self-compatible. In sum, C. hildmannianus is more restrictive and specialized regarding its pollination and breeding system, whereas P. aculeata is more generalist. Understanding the pollination needs of these species is a necessary starting point towards their conservation but also for their proper management and eventual domestication.

The Cancer Genome Atlas effort subtyped gliomas in four molecular groups based on gene expression, mutation and deletion and retrospectively linked these subtypes to chemotherapy response. But up to now there is no protocol to use this or other methods to predict chemotherapy response in the clinic for gliomas. Patients are normally treated with ratiotherapy and temozolomide (TMZ) in a protocol of 5 days of treatment and 23 days of recovery. The goal of this study is to analyze gene expression and drug sensitivity in a relevant time frame to prospectively contribute to therapeutic decisions. For this, we prepared 19 cell cultures from 19 biopsies of brain tumors and treated them with a range of chemotherapy agents (TMZ, carmustine, lomustine, cisplatin, etoposide, paclitaxel, irinotecan, procarbazin, mebendazol, vincristin and vinblastin) at plasmatic concentration. Cells were counted for at least 12 days after treatment or tested for viability after 7 or 14 days and more that 60% reduction was considered a positive response. From eleven cell cultures tested with viability assay, only one responded to temozolomide (the first line chemotherapy for this tumor) after a single administration. The strongest effect was obtained using anti-microtubule agents. Cell counting after 12 days of treatment confirmed the resistance to TMZ and the sensitivity to antimicrotubule drugs, particularly paclitaxel. Combination of procarbazin, lomustine and vincristine (PCV), previously used to treat glioblastoma patients, killed very effectively cells of only 1 patient. The cell cultures from three of five patients display EGFR over-expression and four of five presented p53 and p21 expression. At this time, we are not able to correlate gene expression, subtyping and drug sensitivity. From these data we conclude that brain tumors can be routinely grown and tested for drug sensitivity in a time frame that more closely mimics the treatment of patients. Ethical protocol number UFRGS: 420.856; PUCRS: 429.849 Financial support: FAPERGS, CNPq e CAPES. Citation Format: Franciele C. Kipper, Louise C. Mendonça, Rafael Becker, Gláucia Confortin, Pítia F. Ledur, André Marc, Eliseu Paglioli-Neto, Fabiana Viola, Fernanda B. Morrone, Guido Lenz. In vitro drug sensitivity and genetic profile analysis from primary culture obtained from brain cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4307. doi:10.1158/1538-7445.AM2015-4307

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