Iranian Journal of Pharmaceutical Sciences
Volume:5 Issue: 2, Spring 2009

Extended release formulation of alfuzosin, an a-antagonist used for prostatic hypertrophy, is available in market. It is convenient for older patients to take only one tablet a day. Marketed alfuzosin formulation is three layered geomatrix tablet that requires special facilities, high cost, more time and complex operation than normal direct compression formulation. Therefore, a less complicated formulation is desired which can be prepared by conventional tools. The aim of the study was the development and in vitro evaluation of a controlled release dosage form of a freely soluble weakly basic drug (alfuzosin hydrochloride). Binary mixer of one hydrophilic polymer (hydroxypropyl methylcellulose) and one hydrophobic polymer (ethyl cellulose) was used in tablets prepared by direct compression, 32 factorial design was chosen and the amount of two polymers were taken as independent variables. The percent drug released at 1, 6, 12, and 20 h were selected as response. The main effect and interaction terms were quantitatively evaluated using mathematical model. Dissolution data were fitted to zero order, first order, and Higuchi’s release kinetics to evaluate kinetic data. According to Korsmeyer's equation drug release followed both diffusion and erosion mechanism in all cases. Drug release was different from three fillers (microcrystalline cellulose, lactose and dibasic calcium phosphate).

The objective of the present study was to develop floating microspheres of cefpodoxime proxetil in order to achieve an extended retention in the upper GIT, which may result in enhanced absorption and thereby improved bioavailability. The microspheres were prepared by non-aqueous solvent evaporation method using polymers such as hydroxyl propyl methyl cellulose (HPMC K 15 M), ethyl cellulose in different ratios and cefpodoxime proxetil in each formulation. In vitro drug release were performed by USP apparatus type I and the microspheres were characterized by polymer compatibility by using FT-IR. The yield, particle size, Buoyancy percentage, drug entrapment efficiency, and in vitro drug release were studied. The result showed that microspheres yielded 50.5-72.2%. The particle size was distributed between75-600 μm, drug entrapment efficiency was 14.1-28.2%, and Buoyancy percentage was 70.1-88.3%. The best drug release profiles were seen with formulation 2 at the ratio of drug to polymer of 1:2.

In this study, we investigated the interactive effects of intraperitoneal (i.p.) injections of three different phosphodiesterase inhibitors (PDEIs) on morphine-induced analgesia in mice using tail-flick method. Subcutaneous administration of morphine (1, 3 and 6 mg/kg) caused significant antinociceptive effects in a dose dependent manner. Administration of pentoxifylline (12.5, 25, 50 and 100 mg/kg, i.p.), milrinone (3 and 4.5 mg/kg, i.p.) and theophylline (25, 50 and 100 mg/kg, i.p.) as selective and non-seletive phosphodiesterase inhibitors induced analgesia in mice. We also examined the antinociceptive effects of these three PDEIs in combination with non-effective dose of morphine (1 mg/kg). These combinations increased analgesia effects compared to the either morphine or respective phospho-diestrase inhibitor groups significantly. Our findings strongly suggest that PDEIs can induce analgesia and potentiate morphine antinociception effect via possible interactions on the same molecular or biochemical pathways.

The role of Cu, Zn and Co in human physiology is well documented. Isatin and glycine have inhibitory effects on central nervous system. To capitalize on these features metal complexes of isatin-3-glycine were prepared and evaluated for anticonvulsant activity. The Cu (II) complex was found to be most active among the compounds. The compounds were screened against Staphylococcus aureus, Escherichia coli and Pseudononas aeruginosa. Antimicrobial activity of ligand and its complexes were comparable to that of nitrofurantoin.

In this investigation, hydroxyapatite (HAp) nanostructure with uniform morphologies, controllable size, nano-dispersion and narrow-size distribution in diameter has been synthesized successfully by low-temperature hydrothermal process, and the as-synthesized powders were characterized by energy-dispersive X-ray spectroscopy, scanning electron microscopy, high-resolution transmission electron microscopy (HRTEM), Fourier transform infrared, and induced couple plasma (ICP). In the present work, a novel technique of sono-chemical of CaHPO4.2H2O/NaOH/distilled water with cetyltrimethylammonium bromide ((CH3(CH2)15N+(CH3)3Br-) designated as CTAB) under hydrothermal condition to synthesize HAp nanostructure was described. Furthermore, the usage of a high basic condition a water environment is the two crucial keys in ensuring the formation of HAp the hydrothermal/sonochemical processes. However, the crystallite size and crystallinity degree of the HAp increased with the addition of annealing temperature. Indeed, the present work will introduce new method in synthesis of HAs for scientific and medical engineering.

Hyaluronidase has a panoramic use in biotechnology processes and therapy due to its therapeutic, pathophysiological, physiological and biological importance. Since much of the preparations of hyaluronidases are from animal source (bovine and ovine testicular sources) with limited sources of microbial origin, that prompted the authors to screen and isolate a new promising bacterial strain with higher yield followed by its characterization employing detailed taxonomic studies. The newly isolated strain was identified based upon their micro- and macro-morphological, cultural, physiological and biochemical parameters. Twenty isolates from different pathological samples were primarily selected and further screened for their hyaluronidase producing capabilities by measuring reduction in turbidity and hydrolyzed zone of substrate hyaluronic acid. Four isolates showing marked reduction in turbidity (A600 nm) and hydrolyzed zones were selected and subjected to secondary screening by shake flask fermentation. Isolate SII9 (Dental caries specimen) exhibited maximum hyaluronidase activity (117 U/ml) when compared to the reference Streptococcus mitis MTCC*2695 (106 U/ml). A close scrutiny of the literature revealed that the characteristics of our isolate SII9 are mostly identical to S. equi subsp. equisimilis with few differences and thus designated as S. equi SED 9.

It has been reported that different species of Euphorbia (Euphorbiaceae) have antitumor activity. Some reports also show that these plants have potential cytotoxic effect against different cell lines. In a program to screen the cytotoxicity of Iranian native plants, Euphorbia macroclada Boiss. was collected, identified, and the cytotoxic activity of dichloromethane, ethylacetate, methanol extracts, and the plant latex were determined against MDA-MB-468 cell line. Different concentration of extracts and latex were added to 24 h cultured cells and then incubated for 72 h under specific condition (37 °C, 5% CO2). Cell survival was evaluated using MTT assay. The results of this study indicated that, dichloromethane and ethylacetate extracts had cytotoxic effects on cell line, while the methanol extract and latex were not cytotoxic at the tested concentrations. The data from this investigation suggest that the nonpolar extracts of E. macroclada possess higher cytotoxic activity.

Cell cultures of Varthemia persica DC. have been studied to evaluate their abilities in biotransformation of aromatic and aliphatic precursors. V. Persica (Asteraceae) is an aromatic plant growing in Iran. V. persica contain different terpens but its cell culture does not posses these compounds. Callus cultures of V. persica was established from seedlings and healthy suspensions were grown using Murashige and Skoog (MS) medium supplemented with 2,4-dichlorophenoxy acetic acid (2 mg/l) and kinetin (0.2 mg/l). Then exogenous precursors were fed to V. persica cell suspension cultures. Biotransformation reactions were monitored after 24 h of incubation. The cultures then extracted with dichloromethane or methanol and concentrated within nitrogen stream. The extracts subjected to gas chromatography (GC) or thin layer chromatography (TLC) analysis. V. persica cultured cells in this study seem to exhibit ability in glucosylation of salicylalde-hyde to salicin. No conversion was observed with several precursors fed to the cultures. The ability of cultured plant cells in biotransformation of the precursors appears to be depending on the substrate structure and active enzymes available in the cultures. It seems that in cultured cells of this plant only glucosylation enzymes are active.