Research in Pharmaceutical Sciences
Volume:4 Issue: 2, Oct 2009

A controlled release matrix formulation for mesalamine was designed and developed to achieve a 24 h release profile. Using compritol 888 ATO (glyceryl behenate) as an inert matrix-forming agent to control the release of mesalamine, formulation granules containing the solid dispersions were investigated. Pectin, a polysaccharide, was used as bacterial dependent polymer for colon targeting. The matrix tablets for these formulations were prepared by direct compression and their in vitro release tests were carried out. A 32 full factorial design was used for optimization by taking the amounts of glyceryl behenate (X1) and pectin (X2) as independent variables and percentage drug released at 2 (Q2), 16 (Q16) and 24 (Q24) h as dependent variables. Drug release from the matrix tablets formulations lasted for over 24 h. Images of the tablet surface and cross-section were characterized by scanning electron microscopy to show the formed pores and channels in the matrices. These may provide the release pathway for the inner embedded drugs. The co-mixing of polysaccharide pectin, into the waxy matrices played a meaningful role in targeting the tablets to colon. The drug release from the novel formulation may be attributed to the diffusion-controlled mechanism. The results of the full factorial design indicated that an optimum amount of compritol ATO 888 and a high amount of pectin favors the colon targeting and controlled release of mesalamine from dosage form.

Felodipine is a second generation calcium channel blocker widely used as antihypertensive and antianginal drug which belongs to BCS class II category. Hence, its low water solubility limits the pharmacological effect. The aim of this study was to improve the dissolution rate of felodipine using spherical agglomeration technique with acetone, water and dichloromethane as good solvent, poor solvent and bridging liquid, respectively. The quasi emulsion solvent diffusion technique was used as a method for spherical agglomeration. Inutec SP1 was used as an emulsion stabilizer and as hydrophilic polymer in agglomeration process. The FTIR and DSC results showed no change in the drug after crystallization process. PXRD studies showed sharp peaks in the diffractograms of spherical agglomerates with minor reduction in height of the peaks. The particle size of spherical agglomerates (FI-2) was about 134.33 ± 13.57 µm, n=3 and the dissolution efficiency of felodipine up to 120 min increased to about 4-fold in phosphate buffer containing 1.8% Tween 80 (pH 6.8). Spherical agglomerates showed enhanced solubility compared to untreated powder possibly due to the partial conversion to amorphous form.

Embryonic stem cells are capable of differentiating to variety of cell tissues including cardiomyocytes. This developmental change is accompanied with a great deal of ion channel expression and functions. Mouse stem cell derived cardiomyocytes were prepared and separated to yield isolated single cell suspension for cell current recording. In the present study some properties of the K+-current in Royan B1 stem cell derived cardiomyocytes were investigated using whole cell patch-clamp technique. When the holding potential was -60 mV, in some cells a major outward current was elicited by square depolarizing pulses from -60 mV to +50 mV. This outward current was sustained for the duration of 300 ms test pulse. The sustained outward K+ current was inhibited by tetraethylammonium (10 mM) indicating the activity of Ca2+ activated K+ channel in these cells. In some of the cells with 0.2 mM 3,ethylene glycol-bis (β-aminoethyl ether) N,N,N`,N`-tetraacetic acid in the pipette, only a very small outward current was recorded which suggests that in these cells the voltage activated K+ channels is either absent or if existed it is not fully functional. Other cells were in far between, indicating that voltage activated K+ channels are developing in these cells but it is not yet fully functional. In conclusion, we have identified functional large conductance Ca2+ activated K+ channel in Royan B1 stem cell derived cardiomyocytes.

Teaching pharmacies are amongst the important cornerstones of a healthcare system for drug supplying, pharmacy education and pharmacy practice research. Assessment of the Iranian healthcare system costs shows that after personnel charges, drug outlay is the second expensive factor. This great financial mass requires integral audit and management in order to provide costumers satisfaction in addition to financial viability. Teaching pharmacies are required to realize financial viability as well as providing several educational and drug servicing goals, which makes microeconomic analysis important. The aim of this study was to evaluate the financial performance of the teaching pharmacies affiliated with the Isfahan University of Medical Sciences (with the abrreviated names as: SHM, ISJ, AZH for the confidentialiy of the financial data). This is a descriptive and cross-sectional study done in 2008. The target pharmacies of this study were all the 3 teaching pharmacies affiliated with the Isfahan University of Medical Sciences. The data collecting template was prepared using the standard scientific methods according to the goals of this research The goals also nominated necessary items needed in economic profit evaluation. The data collection template was completed by reference to the teaching pharmacies financial documents and reports, used as a base for calculating the total income and the total costs in 2007-2008 financial year. The difference between these two balances showed the value of profits or loss. The profit/cost ratio was also calculated, using the proportion of the total income to the total costs. The collected data was statistically analyzed using the Excel software (Microsoft 2007). For the financial year 2007-2008, the difference between the total income and the total costs was -831.6 million Rials (excess costs to income) for the SHM pharmacy, + 25.4 billion Rials for the ISJ pharmacy and -429.5 million Rials for the AZH pharmacy. According to our findings there is a strong requirement to improve the financial performance of all the three teaching pharmacies while maintaining a high standardard of teaching and educational affairs.

Acetylcholinesterase (AChE) is the main enzyme for the breakdown of acetylcholine. Nowadays, usage of the inhibitors of this enzyme is one of the most important types of treatment of mild to moderate neurodegenerative diseases such as Alzheimer’s disease. Herbal medicines can be a new source of inhibitors of this enzyme. In this study we examined around 100 different plants to evaluate their inhibitory properties for AChE enzyme. Plants were scientifically identified and their extracts were prepared by methanol percolation. Acetylcholinesterase activity was measured using a colorimetric method in the presence or absence of the extracts. Eserine was used as a positive control. Methanol extracts of the Levisticum officinale, Bergeris integrima and Rheum ribes showed more than 50% AChE inhibitory activity. The inhibition kinetics were studied in the presence of the most effective extracts. L. officinale and B. integrima inhibited AChE activity in a non-competitive manner, while R. ribes competitively inhibitied the enzyme as revealed by double-reciprocal Linweaver-Burk plot analysis. Under controlled condition, Km and Vmax values of the enzyme were found to be 9.4 mM and 0.238 mM/min, respectively. However, in the presence of L. officinale, B. integrima, and R. ribes extracts, Vmax values were 0.192, 0.074 and 0.238 mM/min, respectively. Due to the competitive inhibition of the enzyme by R. ribes extract, the Km value of 21.2 mM was obtained. The concentration required for 50% enzyme inhibition (IC50 value) was 0.5, 0.9, and 0.95 mg/ml for the L. officinale, B. integrima and R. ribes extracts, respectively. The IC50 of the eserine was determined to be 0.8 mg/ml.

The objective of the present study was to evaluate the pharmacokinetic parameters and bioavailability of a selective histamine (H1)-receptor antagonist, cetirizine hydrochloride (CTZ), following administration of a single oral dose of the drug. The properties of a test compound were compared with those of a reference product in a randomized cross-over study in 12 volunteers. Blood samples were collected at selected time intervals up to 24 h and plasma concentrations of CTZ were determined using a validated HPLC method. Pharmacokinetic parameters including T1/2, T1/2 (abs), K, Ka, Tmax, Cmax, Vd/F, Cl/F, AUC0-24, AUC0-∞ and MRT were determined from plasma concentration-time profiles for tested products and found to be in good agreement with previous reports. The analysis of variance did not show any significant differences between the test and reference products. The confidence intervals for the ratio of Cmax (95-110%), AUC0-24 (91-112%) and AUC0-∞ (92-109%) for the test and reference products were within the acceptable interval of 80-125%. ANOVA assessment of logarithmically transformed data did not reveal any significant subject, period or sequence effects. It was, therefore, concluded that the two products were bioequivalent and could be used interchangeably.

In the present study, quantitative relationships between molecular structure and anti-tubercular activity of some 5-methyl/trifluoromethoxy-1H-indole-2,3-dione-3-thiosemicarbazone derivatives were discovered. The detailed application of an efficient linear method and principal component regression (PCR) for the evaluation of quantitative structure activity relationships of the studied compounds is demonstrated. Components produced by principal component analysis were used as the input for a linear model development. Results indicate a linear relationship between the principal components obtained from molecular descriptors and the inhibitory activity of this set of molecules. The maximum variance in the activity of the molecules in PCR method was 73%. The performance of the developed model was tested by several validation methods.

Methanolic extract of 15 Iranian medicinal plants were prepared and tested for their cytotoxic activities against three cancer cell lines (MCF7, HepG2, WEHI164) and one normal cell line (MDBK). Some plants showed cytotoxic activities. The extract of Ferula szowitsiana root, which proved to be the most active, was chosen for further phytochemical studies. The major compounds of the most potent acetone extract were isolated. They were identified as chimgin and chimganin, two known monoterpenoids, by spectroscopic means. Their cytotoxic activity was evaluated in three cell lines. The results show that these compounds are responsible, at least in part, for the cytotoxic activity of this plant.