Feasibility of planctomycetes as a nutritional or supplementary food source for Daphnia spp

Daphnia magna is widely used as a standard organism in ecotoxicology assays. It plays a key role in energy transfer in freshwater food webs as a primary consumer, grazing on microalgae, yeast and bacteria. Daphnids are commonly reared in the laboratory using microalgae cultures but alternative or complementary sources are important to reduce the dependency on a single food source. The role played in nature by planctomycetes as a food source for other higher trophic levels is still unknown. In this study, we aimed to evaluate the potential of Rhodopirellula rubra strain LF2 as a nutritional or a supplementary food source for D. magna and Daphnia longispina. Life-history assays were conducted with daphnids fed with R. rubra in exponential and stationary growth phases, in three concentrations. Additionally, its adequacy as a supplement to the microalga Raphidocelis subcapitata was tested. In general, both daphnids showed impairment in all the parameters evaluated, especially when fed with R. rubra. However, when daphnids were fed with the two food sources, no changes were recorded for the rate of population increase. At the tested concentrations, R. rubra was not a good alternative food source in the daphnid diet. © EDP Sciences, 2016.This research was partially supported by the Strategic Funding UID/Multi/04423/2013 through national funds provided by FCT (Foundation for Science and Technology) and the European Regional Development Fund (ERDF), in the framework of the programme PT2020

Current screening methodologies in drug discovery for selected human diseases

The increase of many deadly diseases like infections by multidrug-resistant bacteria implies re-inventing the wheel on drug discovery. A better comprehension of the metabolisms and regulation of diseases, the increase in knowledge based on the study of disease-born microorganisms’ genomes, the development of more representative disease models and improvement of techniques, technologies, and computation applied to biology are advances that will foster drug discovery in upcoming years. In this paper, several aspects of current methodologies for drug discovery of antibacterial and antifungals, anti-tropical diseases, antibiofilm and antiquorum sensing, anticancer and neuroprotectors are considered. For drug discovery, two different complementary approaches can be applied: classical pharmacology, also known as phenotypic drug discovery, which is the historical basis of drug discovery, and reverse pharmacology, also designated target-based drug discovery. Screening methods based on phenotypic drug discovery have been used to discover new natural products mainly from terrestrial origin. Examples of the discovery of marine natural products are provided. A section on future trends provides a comprehensive overview on recent advances that will foster the pharmaceutical industry. © 2018 by the authors.Acknowledgments: This work was funded by the H2020-TWINN-2015 project BLUEandGREEN (grant 692419). We acknowledge the FCT Project UID/Multi/04423/2013 and the Interreg Atlantic Area project BLUEHUMAN (EAPA_151/2016) funded by the European Regional Development Fund

Eficiência do protocolo Ovsynch em ovelhas da raça Santa Inês

Twenty six Santa Inês ewes were asigned to three treatments to evaluate the efficiency of the Ovsynch protocol. In the treatment 1 - control (n= 8), the estrus was synchronized with sponges containing 60 mg MAP for 14 days. On D14, 300 IU eCG were administered. In treatment 2 (n= 9) the Ovsynch protocol was used: 25 µg of GnRH (D0), 37.5 µg of PGF2a (D7) and 25 µg of GnRH (D9). In treatment 3 (n= 9) the modified Ovsynch protocol was used: the administration of PGF2a and second GnRH as two days early. Estrus detection was accomplished using teaser. All ewes were mated twice with 12 hours of interval. Pregnancy rate (PR) was evaluated by ultrasonography 30 days after the end of mating. Estrus response was of 88.46% on average, and without differences among treatments (p>0.05). The interval for onset of estrus was greater (p0.05). Pregnancy rate was significantly greater (p0,05). O intervalo entre o final do tratamento e o início do estro foi maior (p0,05) entre tratamentos. A TP diferiu entre os grupos (37,5%, 62,5% e 25%, respectivamente. p<0,05). Os resultados mostram eficiência superior do protocolo Ovsynch, sob as restantes condições expe-rimentais

Estudos sobre a nutrição mineral do arroz: XXV. Exigências nutricionais da variedade Dourado Precoce

Rice plants, Dourado Precoce, were grown in nutrient solution in order to study its nutritional requirement as well as the accumulation of dry matter and macro and micronutrients (excet Mo) during the life cycle. Demand for mineral elements followed the following decreasing order: macronutrients -K, N, Ca, Mg and S; micronutrients - Fe, Mn, Cu, Zn and B. Dry matter yield reached a maximun 100 days after germination (DAG), whereas accumulation of elements showed the geghest values at largest (140 DAG).Em condições de solução nutritiva foi cultivado o arroz Dourado Precoce com a finalidade de se estudar a marcha de absorção de nutrientes e as exigências minerais. Verificou-se que as exigências minerais obedecem a seguinte ordem decrescente: macronutrientes -K, N, Ca, Mg e S; micronutrientes -Fe, Mn, Cu, Zn e B. A produção de matéria seca atingiu o pico aos 100 dias após a germinação (DAG). A acumulação de macro e micronutrientes na planta foi, entretanto, máxima no fim do ciclo (140 DAG)