Modulation of Drug Release from Natural Polymer Matrices by Response Surface Methodology: in vitro and in vivo Evaluation.

PURPOSE: The present work aimed at challenging the efficacy of natural gums, karaya and locust bean gum, as matrix-forming polymers for the formulation of sustained-release tablets of diltiazem, a model drug. METHODS: Central design composite was adopted for the formulation and optimization of tablet formulations. The two gums have been selected as independent variables. The dependent factors chosen were the amount of drug released in 1st hour (Y1), amount of drug released after 12 h (Y2), diffusion exponent (Y3), and time for half of the total drug released (T50%) (Y4). Wet granulation approach was used for the formulation of tablets. FT-IR, DSC, in vitro dissolution, swelling-erosion investigations, SEM, and stability studies were carried out. RESULTS AND DISCUSSION: It was evident that the release pattern from the prepared formulations was significantly influenced by the quantity of gum(s) in the tablet. FT-IR and DSC results confirm drug-polymer compatibility. Polynomial equations were used for the prediction of quantitative impact of independent factors at different levels on response variables. After ANOVA analysis, the significant factors were considered for constrained optimization to get the optimized formula. The optimized formula generated by the response surface methodology was evaluated both for in vitro and in vivo properties. The optimized formula and a sustained-release marketed product were subjected to in vivo studies in rabbits and the results of the t-test demonstrated insignificant variation in pharmacokinetic parameters among the two formulations, confirming that the prepared tablet showed sustained-release profile. CONCLUSION: The results indicated that karaya and locust bean gum can be effectively used to formulate sustained-release tablets.

Some Socioeconomic Factors and Lifestyle Habits Influencing the Prevalence of Obesity among Adolescent Male Students in the Hail Region of Saudi Arabia.

A cross-sectional study was conducted to investigate the effect of some socioeconomic factors and lifestyle habits on the prevalence of obesity among adolescent male students in the Hail region, Saudi Arabia. A questionnaire was filled by 1495 male adolescents distributed among 12 schools in the Hail region. Body weight and height were taken, and the Z-score of students was measured using Anthroplus software with a cutoff 1-2 and +2 standard deviations to determine overweight and obesity, respectively. The study revealed that 21.3% of students were overweight and 27% were obese, respectively. There was a negative association between family size of >8 and obesity (OR: 0.68, CI: 0.48-0.92, p = 0.05). Family income of <5000 SR was negatively associated with obesity (OR: 0.59, CI: 0.36-0.97, p = 0.03). Whether a subject's mother worked (odds ratio (OR): 1.43, confidence interval CI: 1.03-1.99, p = 0.03) as well as the subject's mother's education-whether she can read and write, has a middle school degree, or has done postsecondary studies-were positively associated with obesity. Exercise, regardless of the duration, was negatively associated with obesity. In addition, sleeping <6 h/day had a positive association with obesity. CONCLUSION: a >8 family size and a low family income were negatively associated with obesity, while having an educated and working mother was positively associated with obesity.