Private speech in children with ADHD and their typically developing peers during problem-solving and inhibition tasks

This study compared private speech of children with ADHD and normal controls during problem solving and inhibition tasks. Thirty-two children (16 children with ADHD and 16 matched controls) aged 6–11 years participated. Consistent with previous studies, children with ADHD produced more task-irrelevant and task-relevant external private speech than control children during problem-solving tasks, but did not differ in their use of task-relevant internal private speech. During the inhibition/attention task (Continuous Performance Test-II), children with ADHD produced more task-relevant external and more task-relevant internal private speech, suggesting that they may have employed a less mature strategy to aid in self-regulation. The educational implications of the current study are that there should be an increased awareness of the developmental nature and functional significance of private speech and how private speech usage may differ in children with ADHD.     

Medical knowledge discovery systems: data abstraction and performance measurement

Knowledge discovery systems can be traced back to their origin, artificial intelligence and expert systems, but use the modern technique of data mining for the knowledge discovery process. To that end, the technical community views data mining as one step in the knowledge discovery process, while the non-technical community seems to view it as encompassing all of the steps to knowledge discovery. In this exploratory study, we look at medical knowledge discovery systems (MKDSs) by first looking at three examples of expert systems to generate medical knowledge. We then expand on the use of data abstraction as a pre-processing step in the comprehensive task of medical knowledge discovery. Next, we look at how performance of a medical knowledge discovery system is measured. Finally, the conclusions point to a bright future for MKDSs, but an area that needs extensive development to reach its full potential.     

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.