Assessment of oxidative stress and effect of antioxidant supplementation during radiotherapy in carcinoma of upper digestive tract

Oxidative stress was studied by estimating plasma levels of malondialdehyde (MDA), beta carotene, vitamin E and erythrocytic superoxide dismutase(E-SOD) activity in 50 cases of carcinoma of upper digestive tract which included carcinoma of oral cavity, pharynx and oesophagus. While plasma MDA level was found to be increased (3.5±1.0 nmole/ml), a significant decrease in beta carotene (81.2±14.5mg%), vitamin E (8.5±1.1 mg/L) level and E-SOD activity (657.0±80.6 U/G Hb) were observed in carcinoma of upper digestive tract. Patients were treated with radiotherapy which itself was toxic enough and produced its deleterious effects by generation of reactive oxygen species (ROS). As antioxdiants can detoxify ROS, beneficial effect if any, of antioxidant administration during radiotherapy was studied in two groups of patients, group A (n=5, supplemented with antioxidants) and group B (n=5, without antioxidant supplementation). Plasma MDA level was found to be elevated in both the groups but the increase in group B was significant, compared to pretreatment level. Further, body weight was found to be significantly decreased in group B patients, which was maintained in group A patients. Moreover, group A patients showed significant elevation in beta carotene concentration, thus showing beneficial effect of administration of antioxidants during radiotherapy without disturbing the desirable therapeutic effect of radiotherapy.     

Effect of low-dose omega-3 fatty acids substitution on blood pressure, hyperinsulinemia and dyslipidemia in Indians with essential hypertension: A pilot study

The present study comprised 100 patients of essential hypertension who were screened for fasting hyperinsulinemia, which was detected in 77% cases. Twenty such hyperinsulinemic cases were subjected to 4 weeks of dietary control phase followed by 6 weeks of omega-3 fatty acids substitution [either 0.6 g/d (group 1) or 1.2 g/d (group 2)]. The mean basal fasting plasma insulin levels were significantly higher (p<0.001) in patients of hypertension when compared to normal controls (126.51±80.36 and 19.35±12.61 μU/ml respectively). At the end of 4 weeks of diet control only, no significant change was observed in any parameter. After substitution of omega-3 fatty acid, a significant reduction of fasting plasma insulin levels in both group 1 (29%) and group 2 (22.8%) was observed (p<0.001). Significant reduction of systolic and diastolic blood pressure (16.4% and 25% respectively), serum cholesterol, triglycerides and low density lipoprotein was also noted in both groups (p<0.001), while high density lipoprotein increased by ∼8 mg% in both groups. Thus omega-3 fatty acid substituion in low dose along-with curtailment of dietary omega-6 fatty acid may be used as an adjunctive measure in the management of essential hypertension.     

An inverse quasi-static steady-state thermal stresses in a thick circular plate

The present paper deals with the determination of unknown temperature and thermal stresses on the upper surface of a thick circular plate. A thick circular plate is subjected to arbitrary known interior temperature under steady state. The fixed circular edge and lower surface of the circular plate are thermally insulated. The governing heat conduction equation has been solved by using Hankel transform methods. The results are obtained in series form in terms of Bessel's functions. The results for displacement and stresses have been computed numerically and illustrated graphically.     

Adapting mentoring to individual differences in novice teacher learning: the mentor’s viewpoint

Being adaptive to the individual novice teacher is considered a condition for effective teacher mentoring. The aims of this study are therefore to explore (1) mentoring activities through which mentors intend to adapt to the individual novice teacher and (2) characteristics of adaptive mentors. Information was collected through on-site, post-mentoring conversation interviews with 18 mentors holding different mentoring conceptions, from different programs for Initial Teacher Education in the Netherlands. Four adaptive mentoring activities were identified: (1) aligning mutual expectations about the mentoring process, (2) attuning to the novices’ emotional state, (3) adapting the mentoring conversation to match the reflective capacity of the novice teacher, and (4) building tasks from simple to complex relative to the novices’ competence level. Adaptive mentors were (1) more likely to mention activities intended to support construction of personal practical knowledge and (2) less likely to mention activities intended to create a favourable context for novice teacher learning. Suggestions for using findings to enhance mentor adaptiveness are discussed.     

The Effects of Gender Interaction Patterns on Student Participation in Computer-Supported Collaborative Argumentation

In this study we examined response patterns in exchanges between males and females and their effects on gender participation in five online debates. Students classified messages into arguments, evidence, critiques, and elaborations while posting messages to the debates to facilitate argumentation and the sequential analysis of message-response sequences. The findings revealed no differences in number of critiques posted in response to arguments because females were just as likely as males to critique messages from both males and females, and because females responded to males with critiques at a higher than expected frequency. Posthoc analysis revealed strong indications that females posted fewer rebuttals to the critiques of females than males, and males posted more rebuttals to the critiques of females than females. The methods used in this study illustrate a process-oriented approach to explain and predict gender differences in participation and serve as a framework for future research on gender participation, group interaction, and strategies for facilitating collaborative argumentation and problem solving.