Development and biopharmaceutical evaluation of extended release formulation of tramadol hydrochloride based on osmotic technology
Extended release formulation of tramadol hydrochloride (TRH) based on osmotic technology was developed and evaluated. Target release profile was selected and different variables were optimized to achieve it. Formulation variables such as the level of swellable polymer, plasticizer and the coat thickness of semipermeable membrane (SPM) were found to markedly affect drug release. TRH release was directly proportional to the levels of plasticizer but inversely proportional to the levels of swellable polymer and coat thickness of SPM. Drug release from developed formulations was independent of pH and agitation intensity but dependent on osmotic pressure of the release media. In vivo study was also performed on six healthy human volunteers and various pharmacokinetic parameters (cmax, tmax, AUC0-24, MRT) and relative bioavailability were calculated. The in vitro and in vivo results were compared with the performance of two commercial TRH tablets. The developed formulation provided more prolonged and controlled TRH release compared to the marketed formulation. In vitro-in vivo correlation (IVIVC) was analyzed according to the Wagner-Nelson method. The optimized formulation (batch IVB) exhibited good IVIV correlation (R = 0.9750). The manufacturing procedure was found to be reproducible and formulations were stable over 6 months of accelerated stability testing.
The main objective of this paper was to evaluate characteristics of plant community and the present status of soil in natural forest, home garden as well as agroforestry and shifting cultivation. We adopted a very well defined standard methodology for assessing various properties of soil. Plant community attributes were determined for different land use systems. The results showed that the importance value index (IVI) was the highest for natural forest, and then for agroforestry system, home garden while shifting cultivation indicated the least value of IVI. The study clearly shows that soil pH, organic matter content, total nitrogen, calcium, magnesium, and phosphorous under the conditions of the land use systems observed differ significantly from those in natural forest. The changes of topsoil properties and plant characteristics are very distinctive in shifting cultivation (jhuming system, i.e. slash-and-burning farming practice in hilly areas). Thus, the results obtained indicate that once natural forest has been removed, the soilvegetation system is disrupted significantly. The results of this study reveal that shifting cultivation system has negative impact on environment in the region. Furthermore, the land use study carried out based on remote sensing showed that the area of settlement over natural forest has been increasing for last three decades, which results in many environmental problems such as loss of biodiversity, water and soil as well as air pollution
Attention bias modification (ABM) can reduce anxiety and attentional bias towards threatening stimuli, but evidence of its usefulness as a potential intervention for socially anxious individuals has been mixed. Eye contact avoidance, a maladaptive attentional strategy in social anxiety disorder (SAD), has yet to be targeted by ABM research.
This study sought to establish whether a new ABM training paradigm could increase attentional deployment towards eyes and what effect this would have on social and gaze-related anxiety.
Participants (n = 23) recruited through adverts calling for people who felt anxious in social situations completed either a novel ABM training task designed to induce attentional bias towards images of eyes over images of noses, or control training. Data on response times (RTs), accuracy of responses, gaze behaviour (using an eye tracker) and scores on clinical measures of social and gaze-related anxiety were collected before and after both training tasks.
ABM training produced a greater number of initial saccades towards eye images than did the control task, indicating an induced shift in early attentional deployment. ABM training was also associated with a marginal increase in fixation durations on eye images. No effect was observed on RTs or social and gaze-related anxiety.
Our results indicate that ABM can alter the gaze behaviour of socially anxious individuals. They also highlight the importance of eye tracking to ABM research, because it was more sensitive than analyses of RTs to changes in early attentional deployment.