Oxidant and antioxidant status in vegetarians and fish eaters

An adequate antioxidant reserve which is usually present in a vegetarian diet is associated with higher life expectancy. On the other hand habitual consumption of fish is associated with lower risk of cardiovascular diseases which is attributed to the polyunsaturated fatty acids (PUFA) present in it. However the PUFA are readily susceptible to oxidation leading to the formation of free radicals which is known to be involved in the causation of several diseases. The oxidant-antioxidant status of 23 vegetarians and 22 fish eaters was studied by determining the plasma lipid peroxides measured as malondialdehyde (MDA) and the antioxidants, viz. glutathione (GSH), ascorbic acid, ceruloplasmin and uric acid. Results show that the ascorbic acid values were significantly higher in vegetarians. In addition, MDA correlated negatively with ascorbic acid only in vegetarians. However, correlation of MDA with glutathione showed a significant negative correlation only in fish eaters. There was no statistically significant difference in the MDA, GSH, ceruloplasmin and uric acid levels. The mechanism behind these findings are not clear and needs to be explored.     

Strategies in pharmaceutical research

Until comparatively recently the only systematic means of discovering new biologically active substances was laboriously to screen very large numbers of compounds. Now, however, computer graphics is replacing this crude shotgun technique and making it possible to display in some detail the conformation of substances before they are synthesized and determine how far they match the essential features of those in which the biological activity desired has already been demonstrated.     

Technology transfer revisited from the perspective of the knowledge-based economy

This contribution proposes a revised framework for understanding and analyzing the process of technology transfer in the perspective of the knowledge-based economy (KBE). The underlying hypothesis is that the context of the knowledge-based economy introduces a major shift in the way technology transfer is conceived. The traditional model of technology transfer was based on the vision of technology moving from one well-defined economic unit to another well-defined unit. We suggest that in the new perspective technology transfer is essentially considered as a specific knowledge-transfer process that depends on the ways firms and other institutions manage knowledge, in particular the co-evolution of their absorptive capabilities and their knowledge-transmission strategies. To support the theoretical analysis, we analyze the business case of Nortel Networks over the past 50 years.     

Fluorescent probes: a new way to study lymphocyte activation

Fluorescent dyes can be used as cell probes which bind, according to their chemical structure, to particular subcellular regions of lymphocytes. Because of their sensitivity to variations in the local molecular environment, expressed by changes in fluorescence emission, they provide a means of studying the early events of lymphocyte activation to antigens and mitogens. The technology also yields a rapid assay of lymphocyte activation and thus new diagnostic tests of cell-mediated immunity, for example to organ transplants and to cancer.     

Serum and urinary zinc in zinc miners and zinc smelters

Serum (200.6±64.8 mg/dl) and urinary zinc (1186.0±265.5 mg/l.) of zinc miners at Zawar were significantly higher as compared to zinc smelter workers (Serum 89.7±9.9. mg/dl; Urine 590.0±32.1 mg/l.). Debari and Udaipur residents (Serum 104.0±18.6 mg/dl; Urine 735.0±180.2 mg/l.). This was most likely attributable to higher dietary zinc intake by zinc miners due to higher zinc content of foodstuffs grown in Zawar areas as compared to Debari and Udaipur.     

Purification and mechanism of action of antitubercular principle from garlic (Allium sativum) active against isoniazid susceptible and resistantMycobacterium tuberculosis H37Rv

Allicin was prepared from the ethanol extract of garlic without the use of heat. It inhibited the growth ofMycobacterium tuberculosis H₃₇R_v andM. tuberculosis TRC-C 1193 resistant to isoniazid completely when grown as surface cultures as well as shake cultures. The minimum inhibitory concentration (MIC) was 70 μg/ml for both organisms. Further purification of allicin over silica gel-G columns gave a chloroform elutable fraction called CEF-allicin which inhibited the growth of both the susceptible and the isoniazid resistant strains ofM. tuberculosis. Its MIC is 25 μg/ml and is the lowest reported so far when compared with very high inhibitory concentration of 1 to 3mg/ml reported by other workers. It completely inhibited the synthesis of lipids and DNA from¹⁴C-acetate and³H-thymidine respectively and almost completely that of proteins and glycine derived carbohydrates from¹⁴C-glycine ofM. tuberculosis within 6 hr of exposure to CEF-allicin.     

Detection of enzymes dehydrogenases and proteases inBrugia malayi filarial parasites

Lymphatic filariasis caused mainly by infection fromW. bancrofti andB. malayi remains a major cause of clinical morbidity in tropical and subtropical countries. Analysis ofB. malayi mf, infective larval and adult worm lysates for the activity of enzymes led to the demonstration of activities of three key enzymes of carbohydrate metabolism viz., Malate dehydrogenase (MDH), Malic enzyme (ME) and Glucose-6-phosphate dehydrogenase (G6PDH) in all the three stages of the parasite. The specific activity of all the three dehydrogenases was significantly high in mf lysate compared to their activity in lysates of the other two stages (P<0.001). Analysis by native polyacrylamide gel to their activity inlysates of the other two stages (P<0.001). Analysis by native polyacrylamide gel electrophoresis (PAGE) using 7.5% non-gradient gel showed the presence of two isoforms of each of the three enzymes (MDH, ME & G6PDH) in mf lysate, while only one form of each enzyme was present in L₃ larval and adult worm lysates. Further proteolytic enzyme activity was demonstrated both in microfilarial and infective larval lysates ofB. malayi. While both mf and L₃ larval lysates showed optimal protease activity at alkaline pH of 9.0, the mf lysate showed increased activity also at pH 3.0. The infective larval lysate was markedly inhibited by Tosylamide-L-Phenylalanine chloromethyl ketone (TPCK), a thiol protease inhibitor, while the protease activity in mf lysate was significantly inhibited by both TPCK and a serine protease inhibitor Phenyl Methyl Sulphonyl Flouride (PMSF). In sodium do-decyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), using gelatin copolymerized gel, the microfilarial lysate showed 3 protease molecules of 40 kDa, 180 kDa and 200 kDa and the L₃ larval lysate had 6 protease molecules of 18, 25, 37, 49, 70 and 200 kDa size.     

The diffusion of ideas in the academy: A quantitative illustration from economics

It has long been recognised in policy discussion that the influence of new ideas depends not just on their generation but also on the way in which they diffuse through society. However, while the spread of new ideas in industry has been much studied, there are no similar quantitative studies on diffusion within the academy. This paper addresses that gap by providing quantitative evidence on the adoption of two techniques for empirically testing hypotheses in economics. On the basis of this evidence, and contrary to a common expectation, the spread of ideas seems neither straightforward nor especially rapid in the academy.