In-vitro antioxidant and in-vivo anti-inflammatory activities of aerial parts of Cassia species

AbstractCassia species are native to Southeast Asia and sub-Saharan Africa and are commonly used as food and in a broad variety of medicinal applications. Cassia species are widely used in India, but there are few reports in the literature of studies on its chemical compositions and biological properties. In this study, the antioxidant and anti-inflammatory activities of two plants of Cassia species namely Cassia siamea (Lam.) and Cassia javanica (Linn.) were evaluated and the total phenolic compounds and flavonoid contents were determined.The antioxidant activity of the extracts was measured using scavenging of 2,2′-Diphenyl-1-picrylhydrazyl hydrate (DPPH), bleaching of β-carotene and % inhibition of H2O2. The anti-inflammatory activity was evaluated using carrageenan induced paw edema method on Wistar albino rats. The etahnolic extracts of aerial parts of C. siamea and C. javanica were evaluated for in vivo anti-inflammatory activity against the animal model of female Wistar albino rats. Ethanol extracts showed significant and dose-dependent anti-inflammatory effects. The contents of flavonoids and total phenolic compounds could be correlated with the antioxidant and anti-inflammatory activities observed for C. siamea and C. javanica. Our findings suggest that aerial parts of C. siamea and C. javanica contain potential antioxidant and anti-inflammatory compounds, which could be tested as drug candidates against oxidative and inflammation-related pathological processes in medicinal chemistry studies

Interactions between growth-dependent changes in cell size, nutrient supply and cellular elemental stoichiometry of marine Synechococcus

The factors that control elemental ratios within phytoplankton, like carbon:nitrogen:phosphorus (C:N:P), are key to biogeochemical cycles. Previous studies have identified relationships between nutrient-limited growth and elemental ratios in large eukaryotes, but little is known about these interactions in small marine phytoplankton like the globally important Cyanobacteria. To improve our understanding of these interactions in picophytoplankton, we asked how cellular elemental stoichiometry varies as a function of steady-state, N- and P-limited growth in laboratory chemostat cultures of Synechococcus WH8102. By combining empirical data and theoretical modeling, we identified a previously unrecognized factor (growth-dependent variability in cell size) that controls the relationship between nutrient-limited growth and cellular elemental stoichiometry. To predict the cellular elemental stoichiometry of phytoplankton, previous theoretical models rely on the traditional Droop model, which purports that the acquisition of a single limiting nutrient suffices to explain the relationship between a cellular nutrient quota and growth rate. Our study, however, indicates that growth-dependent changes in cell size have an important role in regulating cell nutrient quotas. This key ingredient, along with nutrient-uptake protein regulation, enables our model to predict the cellular elemental stoichiometry of Synechococcus across a range of nutrient-limited conditions. Our analysis also adds to the growth rate hypothesis, suggesting that P-rich biomolecules other than nucleic acids are important drivers of stoichiometric variability in Synechococcus. Lastly, by comparing our data with field observations, our study has important ecological relevance as it provides a framework for understanding and predicting elemental ratios in ocean regions where small phytoplankton like Synechococcus dominates

A survey of trainee specialists experiences at the University of Cape Town (UCT): Impacts of race and gender

<p>Abstract</p> <p>Background</p> <p>Efforts to redress racial and gender inequalities in the training of medical specialists has been a central part of a dedicated programme in the Faculty of Health Sciences at the University of Cape Town (UCT). This study aimed to describe trends in race and gender profiles of postgraduate students in medical specialties (registrars) from 1999 to 2006 and to identify factors affecting recruitment and retention of black and female trainees.</p> <p>Method</p> <p>Review of faculty databases for race and gender data from 1999 to 2006. Distribution of an anonymous self-administered questionnaire to all registrars in 2005/2006.</p> <p>Results</p> <p>The percentage of African registrars doubled from 10% to 19% from 1999 to beyond 2002. The percentages of Africans, Coloureds and Indians rose steadily from 26% to 46% from 1999 to 2005, as did that of women from 27% to 44%. The institution's perceived good reputation, being an alumnus and originating from Cape Town were common reasons for choosing UCT for training. A quarter of respondents reported knowledge of a friend who decided against studying at UCT for reasons which included anticipated racial discrimination. Black respondents (23%), particularly African (50%), were more likely to describe registrarship at UCT as unwelcoming than white respondents (12%). Specific instances of personal experience of discrimination were uncommon and not associated with respondents' race or gender. Registrars who had had a child during registrarship and those reporting discrimination were more likely to rate the learning and research environment as poor (Odds Ratio, 4.01; 95% CI 0.98 – 16.47 and 1.99 95% CI 0.57 – 6.97, respectively).</p> <p>Conclusion</p> <p>The proportion of black and female registrars at the University of Cape Town has increased steadily from 1999 to 2006, most likely a result of systematic equity policies and procedures adopted in the faculty during this period. The data point to a need for policies to make the institution more welcoming to diversity and for strategies to address institutional culture and mentorship, with an aim to develop examples of best practices to share within and between institutions.</p

The Pore-Forming Toxin Listeriolysin O Mediates a Novel Entry Pathway of L. monocytogenes into Human Hepatocytes

Intracellular pathogens have evolved diverse strategies to invade and survive within host cells. Among the most studied facultative intracellular pathogens, Listeria monocytogenes is known to express two invasins-InlA and InlB-that induce bacterial internalization into nonphagocytic cells. The pore-forming toxin listeriolysin O (LLO) facilitates bacterial escape from the internalization vesicle into the cytoplasm, where bacteria divide and undergo cell-to-cell spreading via actin-based motility. In the present study we demonstrate that in addition to InlA and InlB, LLO is required for efficient internalization of L. monocytogenes into human hepatocytes (HepG2). Surprisingly, LLO is an invasion factor sufficient to induce the internalization of noninvasive Listeria innocua or polystyrene beads into host cells in a dose-dependent fashion and at the concentrations produced by L. monocytogenes. To elucidate the mechanisms underlying LLO-induced bacterial entry, we constructed novel LLO derivatives locked at different stages of the toxin assembly on host membranes. We found that LLO-induced bacterial or bead entry only occurs upon LLO pore formation. Scanning electron and fluorescence microscopy studies show that LLO-coated beads stimulate the formation of membrane extensions that ingest the beads into an early endosomal compartment. This LLO-induced internalization pathway is dynamin-and F-actin-dependent, and clathrin-independent. Interestingly, further linking pore formation to bacteria/bead uptake, LLO induces F-actin polymerization in a tyrosine kinase-and pore-dependent fashion. In conclusion, we demonstrate for the first time that a bacterial pathogen perforates the host cell plasma membrane as a strategy to activate the endocytic machinery and gain entry into the host cell

HIGHER EDUCATION IN LASER APPLICATIONS This education offers an opportunity for professional activity ifl R&amp;D and production in many fields of laser applications

ABSTRACT Problems o+ special tiigti education in laser applications are discussed. Education in the field of laser techniques, applied optics, interaction of laser radiation with matter is imperative and in demand +or many application areas. At laser technology chair 5t.PIFMO, besides laser technology, the basic education in three subject areas of laser applications is given: lasers in environment studies, laser medicine and laser safety. The education in laser technology is considered in more detail. The information about optical systems for technological lasers, laser techniques and physics, and laser beam interaction with solids are given in theoretical courses, in laboratories of lasers in microelectronics and lasers in optics technology and in the practical classes

Evaluation of Phenolic Content and Antioxidant Capacity of Eleusine coracana (L.)

The aim of this study is to evaluate the content of phenolics: total seven phenolic acids and one flavonoid were separated from the species of Eleusine coracana (L.). The separated phenolics were characterized by various spectral techniques. The antioxidant capacity of all phenolics was determined by rancimat study of sunflower oil using control and standard drugs like Glipizide and Metformin. The stability period of sunflower oil was found to increase from 0.89 hr to 1.04 hr in presence of eight extracted ingredients of Eleusine coracana (L.), which was compared with result of neat sunflower oil