348 research outputs found

    Health-Beneficial Phenolic Aldehyde in Antigonon leptopus Tea

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    Tea prepared from the aerial parts of Antigonon leptopus is used as a remedy for cold and pain relief in many countries. In this study, A. leptopus tea, prepared from the dried aerial parts, was evaluated for lipid peroxidation (LPO) and cyclooxygenase (COX-1 and COX-2) enzyme inhibitory activities. The tea as a dried extract inhibited LPO, COX-1 and COX-2 enzymes by 78%, 38% and 89%, respectively, at 100 μg/mL. Bioassay-guided fractionation of the extract yielded a selective COX-2 enzyme inhibitory phenolic aldehyde, 2,3,4-trihydroxy benzaldehyde. Also, it showed LPO inhibitory activity by 68.3% at 6.25 μg/mL. Therefore, we have studied other hydroxy benzaldehydes and their methoxy analogs for LPO, COX-1 and COX-2 enzymes inhibitory activities and found that compound 1 gave the highest COX-2 enzyme inhibitory activity as indicated by a 50% inhibitory concentration (IC50) at 9.7 μg/mL. The analogs showed only marginal LPO activity at 6.25 μg/mL. The hydroxy analogs 6, 7 and 9 showed 55%, 61% and 43% of COX-2 inhibition at 100 μg/mL. However, hydroxy benzaldehydes 3 and 12 showed selective COX-1 inhibition while compounds 4 and 10 gave little or no COX-2 enzyme inhibition at 100 μg/mL. At the same concentration, compounds 14, 21 and 22 inhibited COX-1 by 83, 85 and 70%, respectively. Similarly, compounds 18, 19 and 23 inhibited COX-2 by 68%, 72% and 70%, at 100 μg/mL. This is the first report on the isolation of compound 1 from A. leptopus tea with selective COX-2 enzyme and LPO inhibitory activities

    Infrared absorbance spectroscopy of aqueous proteins : comparison of transmission and ATR data collection and analysis for secondary structure fitting

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    Attenuated total reflectance (ATR) infrared absorbance spectroscopy of proteins in aqueous solution is much easier to perform than transmission spectroscopy, where short path‐length cells need to be assembled reproducibly. However, the shape of the resulting ATR infrared spectrum varies with the refractive index of the sample and the instrument configuration. Refractive index in turn depends on the absorbance of the sample. In this work, it is shown that a room temperature triglycine sulfate detector and a ZnSe ATR unit can be used to collect reproducible spectra of proteins. A simple method for transforming the protein ATR spectrum into the shape of the transmission spectrum is also given, which proceeds by approximating a Kramers‐Krönig–determined refractive index of water as a sum of four linear components across the amide I and II regions. The light intensity at the crystal surface (with 45° incidence) and its rate of decay away from the surface is determined as a function of the wave number–dependent refractive index as well as the decay of the evanescent wave from the surface. The result is a single correction factor at each wave number. The spectra were normalized to a maximum of 1 between 1600 cm−1 and 1700 cm−1 and a self‐organizing map secondary structure fitting algorithm, SOMSpec, applied using the BioTools reference set. The resulting secondary structure estimates are encouraging for the future of ATR spectroscopy for biopharmaceutical characterization and quality control applications

    Shaping the research experiences of graduate students using action research

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    s u m m a r y a r t i c l e i n f o Background: Nursing research capacity is often not optimal in developing countries. Capacity building at the graduate nurse level presents an opportunity for improved research output. Students pursuing a research methods course at a nursing school in Jamaica expressed fear and anxiety towards the course. Action research was used to address this fear and improve learning outcomes. Objective: To determine attitudes towards research and to improve the experience of graduate students pursuing a research methods course at a nursing school in Jamaica. Methods: Students (n = 44) registered in the Research Methods course of the MScN at a nursing school in Kingston, Jamaica for the academic year 2010/2011, were invited to participate. Each student was assigned a main supervisor and an alternate supervisor and all had equal access to the course leader and content. On completion of the course three focus group discussions of 10-14 students per group were conducted to determine how students felt about the course experience and their attitude towards the course. Results: Thirty-seven students (mean age of 41.4 ± 1.5 years; 94% female) participated in the exploratory course evaluation exercise. The participants reported that they entered research methods with feelings of apprehension and anxiety. However, these fears were allayed by a combination of factors including interest in students' welfare, affirmation of students, respect for and understanding of students' needs and resourcefulness, and the use of a panel of experts. Barriers included faculty's unrealistic expectations of students' research competencies and the limited time in which to learn and apply concepts. While students thought the course as challenging they felt more confident that they could be successful on completion of the course. Conclusion: Significant improvement in attitudes to research was realized among graduate nursing students using action research at an urban school of nursing in Jamaica

    Parastrongylus cantonensis in a Nonhuman Primate, Florida

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    Parastrongylus (= Angiostrongylus) cantonensis is a parasitic nematode of Norway rats throughout tropical regions. This parasite is neurotropic and causes disease and death in humans and other mammals. We report the first identification of P. cantonensis as the cause of a debilitating neurologic disease in a captive primate in Florida

    Minimizing Game Score Violations in College Football Rankings

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