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Herbivoria de Bosmina freyi e suas relações ecológicas no Reservatório de Itupararanga - Votorantim/SP
(Universidade Federal de São Carlos, 2014-05-07) Magalhães, Raphaella de Abreu; Santos, André Cordeiro Alves dos; https://lattes.cnpq.br/2131880667704281; https://lattes.cnpq.br/7397911787609992
Preliminary studies on reservoir Itupararanga indicate that the seasonal dynamics of plankton community is not being strongly controlled by bottom-up forces. Cianobactéria Cylindrospermopsis raciborskii and clorofícea Monoraphidium contortum are the dominant phytoplankton species in this reservoir. Bosmina freyi, recently described, is the dominant zooplankton in Itupararanga and there is no records of studies feeding habits of this specie. Therefore, the present study aims to assess the importance of the cladoceran Bosmina freyi as consumers of phytoplankton species: Monoraphidium contortum and Cylindrospermopsis raciborkii to better understand the ecological role of this organism in the planktonic food web in reservoir Itupararanga. M. contortum and three types of strain C.raciborskii, toxic strain (Cy.tox), strain with large filaments (Cy.grd) and strain with small filaments (Cy.peq) where ofered for Bosmina freyi. For each treatment, were calculated the density, cell volume, biovolume before and after incubation with B. freyi.Also calculated the ingestion and filtration rates. Qualitative models have also been made to describe and make predictions on the plankton community Itupararanga when there are changes in the population of Chaoborus sp. It was noted that B. freyi is able to efficiently ingest C.raciborskii including toxic strain, but presented difficulties in filter and ingest filaments of Cy.grd.Besides, B.freyi seems to be able to cut up filaments of C.raciborskii for ingestion. No food preference was observed by M.contortum. Qualitative models made in this study corroborate the hypothesis that seasonal variations in plankton reservoir Itupararanga may be being controlled by top-down forces due the presence of Chaoborus sp.
Efeitos antitumorais da naringenina complexada com cobre (II) e 2,2 -bipiridina em células de câncer de mama
(Universidade Federal de São Carlos, 2014-05-07) Conceição Filho, Júlio César; Cominetti, Márcia Regina; https://lattes.cnpq.br/1613484530528398
Cancer, is the name given to a set of more than 100 diseases that have in common the uncontrolled growth of cells that invade tissues and organs. It is occurs for several reasons, among them changes in DNA that may be caused by many factors such as oxidative stress, exposure to sunlight and smoking. Many efforts are being made in the search for treatments that may prolong a patient's life or even cure of the disease. In this quest, many chemotherapeutic compounds have been developed in an attempt to combat the different types of cancer. Among these various compounds were developed directly or indirectly from natural products derived from plants or bioactive compounds such as camptothecin, extracted from the bark of Camptotheca acuminata plant and taxol derivative of Taxus brevifolia. Flavonoids are a group of secondary metabolites, which belong to the class of polyphenols. They are found in several species of plants, especially in fruits, seeds and flowers. Many of them were described as having high antioxidant, anti-inflammatory, antiallergic, hepatoprotective and antitumor capacity. The main groups are derived from flavonoids are: flavanols, flavonols, isoflavones, anthocyanidins, flavonones, and flavones. The naringenin belongs to the group of flavonones commonly found in citrus fruits and has shown in previous studies to possess anti-tumor action. To make more effective the action of these compounds, many have been linked to metal complexes which increases the cytotoxicity of the same. One of the biggest challenges in the field of cancer research is to obtain a chemotherapeutic compound that is cytotoxic to tumor cells only and has fewer side effects compared to drugs currently used. Thus, the aim of this study was to evaluate and compare the cytotoxic effect of naringenin and naringenin complexed with copper and 2,2 '-bipyridine, in triple-negative breast cancer cell line, MDA-MB-231 and understand some of the mechanisms molecular action involved.