415 research outputs found
Antioxidant activity and phytochemical characterization of senecio clivicolus wedd
No full textAntioxidant phytochemicals play a key role in oxidative stress control and in the prevention of related disorders, such as premature aging, degenerative diseases, diabetes, and cancer. The aim of this study was to investigate the potential antioxidant activity and the phytochemical profile of Senecio clivicolus Wedd., a perennial shrub, belonging to the Asteraceae family. Despite the wide interest of this family, this specie has not been investigated yet. S. clivicolus aerial parts were extracted with 96% ethanol. Then, the ethanol extract was fractionated by liquid/liquid extraction using an increasing solvents polarity. Total polyphenol and terpenoid contents were measured. Moreover, the antioxidant activity was evaluated by six different complementary in vitro assays. The Relative Antioxidant Capacity Index (RACI) was used to compare data obtained by different tests. The sample showing the highest RACI was subjected to characterization and quantitation of its phenolic composition using LC-MS/MS analysis. The ethyl acetate fraction, investigated by LC-MS/MS analysis, showed 30 compounds, most of them are chlorogenic acid and flavonoid derivatives. To the best of our knowledge, this is the first report about the evaluation of antioxidant activity and phytochemical profile of S. clivicolus, underlying the importance of this species as a source of health-promoting phytochemicals
Role of Risk Stratification and Genetics in Sudden Cardiac Death
No full textSudden cardiac death (SCD) is a major public health issue due to its increasing incidence in the general population and the difficulty in identifying high-risk individuals. Nearly 300,000-350,000 patients in the United States and 4- to 5 million patients in the world die from SCD. Coronary artery disease and advanced heart failure are the main etiology for SCD. Ischemia of any cause precipitates lethal arrhythmias, and ventricular tachycardia and ventricular fibrillation are the most common lethal arrhythmias precipitating SCD. Pulse-less electrical activity, brady-arrhythmia and electromechanical dissociation also result in SCD. Most sudden cardiac deaths occur out-of-the-hospital setting, so it is difficult to estimate the public burden, which results in overestimating the incidence of SCD. The insufficiency and limited predictive value of various indicators and criteria for SCD result in the increasing incidences. As a result, there is a need to develop better risk stratification criteria and find modifiable variables to decrease the incidence. Primary and secondary prevention and treatment of SCD need further research. This critical review is focused on the etiology, risk factors, prognostic factors and importance of risk stratification of SCD.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author
The use of mass spectrometry and DNA technology in the investigation of hemoglobin disorders
No full textHemoglobin (Hb) disorders, which severely affect nearly 300,000 newborns every year, have become a global problem. The disorders manifest a wide spectrum of clinical symptoms ranging from asymptomatic to lethal conditions. Inheritance or spontaneous occurrence of genetic defects could lead to either a structural abnormality of Hb (Hb variants) or an impaired or no synthesis of the globin chains (thalassemias). The majority of Hb variants are caused by a single nucleotide substitution resulting in an amino acid change in the globin chain, while the thalassemias are caused by a diverse array of mutations.The study of Hb disorders can elucidate the structure- function relationship of the Hb and may clarify the mechanism of pathogenesis. Hb disorders are good models of protein abnormalities that can be directly or indirectly associated with molecular diseases. Conventional electrophoresis and HPLC techniques give presumptive identification of Hb variants and are still widely used today. Modem developments in DNA technology have revolutionized detection and identification of Hb disorders at the nucleotide level. Simultaneously, mass spectrometry has emerged as a powerful tool in the field of biological and biomedical studies. Proteins of almost unlimited molecular mass can be analyzed and amino acid sequence of peptides can be readily determined.In order to evaluate the performance and limits of DNA and electrospray mass spectrometry techniques in the investigation of Hb variants, different studies using these techniques were initiated. The mass spectrometric experiments were done at two levels, i.e. at the intact globin chain and at the tryptic peptide levels. The mass analyses were performed on two-step diluted whole blood samples requiring only 10 µL of the whole blood. Blood samples stored at +4° C or -20° C were used. The variants which were present to greater than 10% of the total Hb, and whose masses differed by greater than 6 Da from the normal chain were in most cases readily identified by electrospray mass spectrometry. Data from isoelectric focusing and a knowledge of the genetic code greatly aided the characterization of Hb variants.Accurate mass measurements (A secondary structural change in Hb variants, i.e. disulfide bridge, was also demonstrated and characterized by mass spectrometry. However, due to the complexity of the peptide mixture, DNA analyses were sometimes required to allow successful interpretation of mass spectrometry data. In general, mass spectrometry was a powerful tool for screening and identification of aberrant Hb proteins.List of scientific papersI. Rai DK, Alvelius G, Landin B, Griffiths WJ (2000). Electrospray tandem mass spectrometry in the rapid identification of alpha-chain haemoglobin variants. Rapid Commun Mass Spectrom. 14(14): 1184-94. https://pubmed.ncbi.nlm.nih.gov/10918366II. Rai DK, Landin B, Alvelius G, Griffiths WJ (2002). Electrospray tandem mass spectrometry of intact beta-chain hemoglobin variants. Anal Chem. 74(9): 2097-102. https://pubmed.ncbi.nlm.nih.gov/12033312III. Rai DK, Landin B, Griffiths WJ, Alvelius G, Green BN (2002). Characterization of the elusive disulfide bridge forming human Hb variant: Hb Ta-Li beta83 (EF7)Gly --> Cys by electrospray mass spectrometry. J Am Soc Mass Spectrom. 13(2): 187-91. https://pubmed.ncbi.nlm.nih.gov/11838022IV. Rai DK, Griffiths WJ, Alvelius G, Landin B (2001). Electrospray mass spectrometry: an efficient method to detect silent hemoglobin variants causing erythrocytosis. Clin Chem. 47(7): 1308-11. https://pubmed.ncbi.nlm.nih.gov/11427466V. Rai DK, Griffiths WJ, Landin B, Wild BJ, Alvelius G, Green BN (2003). Accurate mass measurement by electrospray ionization quadrople mass spectrometry: detection of variants differing by <6 Da from normal in human hemoglobin heterozygotes. [Manuscript]</p
Profiling of Phytochemicals in Tissues from Sclerocarya birrea by HPLC-MS and Their Link with Antioxidant Activity
No full textHighperformance liquid chromatography-tandemmass spectrometry (HPLC-MS/MS) was employed to investigate the differences
in phytochemicals in roots, bark, and leaf of Sclerocarya birrea(marula) for methanol and water extracts that exhibited the best
antioxidant activities.Asmany as 36compoundswereobserved in the extracts of these tissues ofwhich27phenolic compoundswere
tentatively identified. The HPLC-MS/MS results showed flavonoid glycosides were prominent in leaf extracts while the galloylated
tannins were largely in bark and root extracts. Four flavonoid glycosides that were reported for the first time in themarula leaf have
been identified.TheHPLC-MS/MS studies also illustrated different degrees (highest degree = 3) of oligomerisation and galloylation
of tannins in the bark and root extracts
Comprehensive Characterization and Quantification of Antioxidant Compounds in Finger Lime (<i>Citrus australasica</i> L.) by HPLC-QTof-MS and UPLC-MS/MS
No full textAustralian finger limes (Citrus australasica L.), an unusual citrus due to its unique pulp with a caviar-like appearance, has reached the global market as a promising source of bioactive compounds that promote health. This research was, therefore, performed to shed light on the bioactivity and composition of different parts of Citrus australasica L. (peel and pulp). Initial ultrasound-assisted extraction using MeOH:H2O (80:20, v/v) was carried out. After that, four fractions (hexane, ethyl acetate, butanol and water) were generated through liquid–liquid partitioning, and the total phenolic content (TPC) and antioxidant activity were evaluated using the Folin–Ciocalteu and the ferric reducing antioxidant power (FRAP) assays, respectively. The ethyl acetate fraction in the peel, which presented the highest values of TPC and antioxidant activity, was characterized using high-performance liquid chromatography coupled to quadrupole time-of-flight (HPLC-QTof) mass spectrometry. Fifteen compounds were identified, of which seven were characterized for the first time in this matrix. Moreover, ten phenolic compounds were quantified using ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS). The major compounds in the sample were citric acid, pyrogallol, caffeic acid, coumarin, rutin, naringin, 2-coumaric acid, didymin, naringenin and isorhamnetin, which were found in a range from 2.7 to 8106.7 µg/g sample dry weight. Finally, the results presented in this novel work confirmed that the peel by-product of C. australasica L. is a potential source of bioactive compounds and could result in a positive outcome for the food, cosmetics and pharmaceutical industries
Bollywood cinema: A critical genealogy
No full text"Bollywood" has finally made it to the Oxford English Dictionary. The 2005 edition defines it as: "a name for the Indian popular film industry, based in Bombay. Origin 1970s. Blend of Bombay and Hollywood." The incorporation of the word in the OED acknowledges the strength of a film industry which, with the coming of sound in 1931, has produced some 9,000 films. (This must not be confused with the output of Indian cinema generally, which would be four times more). What is less evident from the OED definition is the way in which the word has acquired its current meaning and has displaced its earlier descriptors (Bombay Cinema, Indian Popular Cinema, Hindi Cinema), functioning, perhaps even horrifyingly, as an "empty signifier" (Prasad) that may be variously used for a reading of popular Indian cinema. The triumph of the term (over the others) is nothing less than spectacular and indicates, furthermore, the growing global sweep of this cinema not just as cinema qua cinema but as cinema qua social effects and national cultural coding. Although Indian film producers in particular, and pockets of Indian spectators generally, continue to feel uneasy with it (the vernacular press came around to using "Bollywood" only reluctantly), its ascendancy has been such that Bombay Dreams (the Andrew Lloyd Weber musical) and the homegrown Merchants of Bollywood both become signifiers of a cultural logic which transcends cinema and is a global marker of Indian modernity. As the Melbourne (March 2006) closing ceremony of the Commonwealth Games showed, Bollywood will be the cultural practice through which Indian national culture will be projected when the games are held in Delhi in 2010. International games (the Olympics, World Cup Soccer, Asian Games, Commonwealth Games, and so on) are often expressions of a nation's own emerging modernity. For India that modernity, in the realm of culture, is increasingly being interpellated by Bollywood
Antioxidant, antidiabetic, and anticholinesterase activities and phytochemical profile of Azorella glabra wedd
No full textOxidative stress is involved in different diseases, such as diabetes and neurodegenerative diseases. The genus Azorella includes about 70 species of flowering plant species; most of them are commonly used as food and in particular as a tea infusion in the Andean region of South America in folk medicine to treat various chronic diseases. Azorella glabra Wedd. aerial parts were firstly analyzed for their in vitro antioxidant activity using different complementary assays. In particular, radical scavenging activity was tested against biological neutral radical DPPH; ferric reducing power and lipid peroxidation inhibitory capacity (FRAP and Beta-Carotene Bleaching tests) were also determined. The Relative Antioxidant Capacity Index (RACI) was used to compare data obtained by different assays. Then, the inhibitory ability of samples was investigated against α-amylase and α-glucosidase enzymes involved in diabetes and against acetylcholinesterase and butyrylcholinesterase enzymes considered as strategy for the treatment of Parkinson’s or Alzheimer’s diseases. Moreover, the phytochemical profile of the sample showing the highest RACI (1.35) and interesting enzymatic activities (IC50 of 163.54 ± 9.72 and 215.29 ± 17.10 μg/mL in α-glucosidase and acetylcholinesterase inhibition, respectively) was subjected to characterization and quantification of its phenolic composition using LC-MS/MS analysis. In fact, the ethyl acetate fraction derived from ethanol extract by liquid/liquid extraction showed 29 compounds, most of them are cinnamic acid derivatives, flavonoid derivatives, and a terpene. To the best of our knowledge, this is the first report about the evaluation of significant biological activities and phytochemical profile of A. glabra, an important source of health-promoting phytochemical
Asian Economic Integration and Cooperation: Challenges and Ways Forward for Pan-Asian Regionalism
No full textAs the Asian economies have grown larger and become more complex, they have also be-come more integrated at both the regional and the subregional level. Yet although economic integration has increased, regionalism in the sense of economic cooperation at both the pan-Asian and subregional levels has lagged behind. Regionalism or economic cooperation in terms of bilateral or multilateral FTAs is a relatively new phenomenon, but one that has in-creased rapidly in recent years. However, the progress of Asian regionalism faces several challenges. Also, the increasing number of FTAs could lead to a “spaghetti-bowl effect” and reduce trade volume instead of increasing it. In addition to resolving the existing challenges, actors in the region need to convert some of the existing FTAs into a broader one that can serve as a hub for further integration. Given the potential economic gains and future eco-nomic dynamism of the region, this paper suggests the pursuit of the Comprehensive Eco-nomic Partnership in East Asia (CEPEA) rather than the East Asia Free Trade Area (EAFTA).economic integration, regionalism, economic cooperation, ASEAN, SAARC, spaghetti-bowl effect, FTAs
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