Anatomical, Histochemical and Biological Studies of Clusia grandiflora Splitg. (Clusiaceae)

Abstract Clusia grandiflora belongs to an important botanical family which is known for its medicinal value, however there are few reports in literature about the species, highlighting the relevance of this study. Anatomical studies with leaves and stems were performed using traditional techniques. In this investigation it was identified particularities of the species such as the presence of vascular system arranged in an opened arc-shaped with the flexed ends towards the inside of the arch with accessory bundles in the petiole. In histochemical studies, performed with different reagents, alkaloids, phenols substances, carbohydrates and lipids were located. The cytotoxic activity of the extracts was performed by tetrazole salt and showed promising results for ethanolic extracts of stems (IC50 human colon cells of 24.30 μg/ mL) and leaves (IC50 ascites gastric cells of 44.15 μg/ mL), without cell membrane disruption of erythrocytes. The antibacterial activity was evaluated by tryptic soy agar and minimal inhibitory concentration assays and showed positive results for Pseudomonas aeruginosa and Escherichia coli, with better result for adventitious roots (32 μg/ mL and 16 μg/ mL, respectively), stems (64 μg/ mL and 32 μg/ mL, respectively) and leaves (64 μg/ mL and 32 μg/ mL, respectively) ethanolic extracts. Thus, these studies were able to characterize the species and show its potential as promising source of active substances.

Staphylococcus aureus: visitando uma cepa de importância hospitalar / Staphylococcus aureus: visiting a strain of clinical importance

O Staphylococcus aureus é uma bactéria do grupo dos cocos gram-positivos que faz parte da microbiota humana, mas que pode provocar doenças que vão desde uma infecção simples, como espinhas e furúnculos, até as mais graves, como pneumonia, meningite, endocardite, síndrome do choque tóxico e septicemia, entre outras. Essa bactéria foi uma das primeiras a serem controladas com a descoberta dos antibióticos, mas, devido a sua enorme capacidade de adaptação e resistência, tornou-se uma das espécies de maior importância no quadro das infecções hospitalares e comunitárias. Neste artigo faremos uma revisão sobre esse agente infeccioso e as bases dos mecanismos das patologias por ele provocadas, de forma a ressaltar a necessidade de mantê-lo como alvo para o desenho de novos antibióticos.

Staphylococcus aureus is a bacterium from Gram-positive coccus group, which is part of the human microbiota. It may cause diseases that may vary from simple infections (i.e., pimples and furuncles) to severe infections, such as pneumonia, meningitis, endocarditis, toxic shock syndrome and septicemia, among others. This bacterium was one of the first bacteria affected by antibacterial agents, however, its ability of adaptation and resistance turns it into an important hospital and communitarian pathogenic species of great concern. In this article we will discuss some important points related to the S. aureus and the pathologies related to it to reinforce it as a target for the design of new antibiotics.

Plaquetas: ainda um alvo terapêutico / Platelets: still a therapeutical target

As plaquetas são fragmentos citoplasmáticos anucleados presentes no sangue e produzidos na medula óssea a partir dos megacariócitos. O objetivo deste trabalho é rever as bases mecanísticas e moleculares das plaquetas, revelando sua participação em síndromes importantes e na trombose arterial, além de seu potencial como alvo terapêutico para o desenho de novos agentes antitrombóticos.

Platelets are cytoplasmatic fragments from bone marrow megakaryocytes present on blood. The aim of this work is to review the basis of platelet mechanisms, their participation in syndromes and in arterial thrombosis, and its potential as a target for design of antithrombotic agents.