DARU, Journal of Pharmaceutical Sciences
Volume:13 Issue: 2, Summer 2005

Abstract: The urea breath test (UBT) which is carried out with 13C or 14C labeled urea is one of the most important non invasive methods for detection of Helicobacter pylori infection. Application of 13C-UBT is becoming increasingly popular because of its non radioactive nature which makes it suitable for diagnostic purposes in children and women of child bearing ages. While isotope ratio mass spectrometer (IRMS) is generally used to detect 13C in expired breath, this instrument is expensive and recently non dispersive isotope selective infrared (NDIR) spectroscopy which is a lower cost technique has been employed as a reliable counterpart for IRMS in small clinics. The aim of this study was to assess the validity of NDIR spectroscopy technique in Iranian population in comparison with histological examination, rapid urease test and 14C-urea breath test as gold standard. Seventy six patients with dyspepsia were underwent 13CUBT for diagnosis of Helicobacter pylori infection. Good agreements were found between the 13C-UBT and gold standard methods. The 13C-UBT showed 100% sensitivity, 97.3% specificity, 97.56% positive predictive value, 100% negative predictive value and 98.65% accuracy. On the basis of these results it could be concluded that 13C-UBT performed with NDIR spectroscopy is a reliable, accurate and non invasive diagnostic tool for detection of Helicobacter pylori infection in the Iranian population.

Abstract: Solubility of sulphamethoxazole, sulphisoxazole and sulphasalazine in six solvents namely water,methanol, ethanol, 1-propanol, acetone and chloroform were determined at 15, 25, 37 and 45 °C. Two models derived from the Hildebrand solubility approach are proposed for solubility prediction at different temperatures using a single determination. The experimental data of the present work as well as data gathered from the literature have been employed to investigate the accuracy and prediction capability of the proposed models. The overall percent deviations between the predicted and experimental values were 10.78 and 14.63% which were comparable to those of the classical two and three parameter models. The proposed models were much superior to the two pure predictive models i.e., the ones which do not require experimental solubility determination, as the overall percent deviations produced by the latter models were 150.09 and 161.00%.

Abstract: A simple, sensitive and specific HPLC method and also a simple and fast extraction procedure were developed for quantitative analysis of fentanyl transdermal patches. Chloroform, methanol and ethanol were used as extracting solvents with recovery percent of 92.1, 94.3 and 99.4% respectively. Fentanyl was extracted with ethanol and the eluted fentanyl through the C18 column was monitored by UV detection at 230 nm. The linearity was at the range of 0.5-10 µg/mL with correlation coefficient (r2) of 0.9992. Both intra and inter-day accuracy and precision were within acceptable limits. The detection limit (DL) and quantitation limit (QL) were 0.15 and 0.5 µg/mL, respectively. Other validation characteristics such as selectivity, robustness and ruggedness were evaluated. Following method validation, a system suitability test (SST) including capacity factor (k´), plate number (N), tailing factor (T), and RSD was defined for routine test.

Abstract: The possibility of enhancment accumulation of podophyllotoxin (PTOX) has been studied in cultures of cell suspension of Linum album Kotschy ex Boiss. (Linaceae) producing PTOX was studied. Attempts were made to manipulate the biosynthetic pathway of PTOX by some biotic (yeast extract) and abiotic (Ag+, Pb2+ and Cd2+) elicitors for 24 or 48 hr in Murashige and Skoog (MS) medium. Silver significantly enhanced PTOX production up to 0.24 % (mg/g cell dry wt.) in cultures. This effect could be attributed to the inhibitory role of silver on production of ethylene.

Abstract: Nepeta is a one of the most important genera of the Lamiaceae family with regard to the number of species. Some species of this genus are important medicinal plants and their extracts have been used for medicinal purposes. In this investigation aerial parts of Nepeta sintenisii Bornm. was subjected to hydrodistillation and the chemical composition of the isolated essential oil was analyzed by GC/MS method for first time. Forty constituents (96.5% of the total oil) were identified of which 4aβ,7α,7aβ-nepetalactone (23.4%), elemol (16.1%), E-β-farnesene (9.5%), 1,8-cineole (8.2%), cis-sabinene hydrate (6.5%), β-bisabolene (4.2%) and germacrene-D (3.5%) were the main components. The constituents of the volatile oil of N. sintenisii is similar to the composition of the other Nepeta genus.

Abstract: Echium amoenum Fisch. and C.A. Mey. (Boraginaceae) is an indigenous Iranian plant, that its dry violet–blue petals (Gol-e-Gavzaban) have long been used in traditional medicine of Iran. In this study concentrated metanolic extract of the grounded dried petals of E. amoenum was fractionated by column chromatography and the fractions were purified by preparative HPLC. The structure of main pure component which was characterized by UV, IR, one and two dimensional 1H and 13C-NMR and Mass spectroscopy was found to be rosmarinic acid which is widespread in the plants of the Lamiaceae and Boraginaceae families in insignificant quantities and has antimicrobial, antiviral, and anti-inflammatory effects.

On the basis of reports that ginger (Zingiber officinale, Z. officinale) extract has antiinfalammatory activity, the present study was undertaken to investigate whether the aqueous extract of Z. officinale has any significant beneficial effect on chronic inflammation in diabetic mice. Control mice received normal saline (0.1 ml, i.p.), and in the test group, diabetes was induced by injection of streptozotocin (STZ, 180mg/kg, i.p.) which was confirmed by the measurement of blood glucose, 7 days after STZ injection. One week after saline or STZ injection, chronic inflammation was induced by implantation of cotton pellets (30 mg) on each side of the groin region subcutaneously. Then at the day of 3, the aqueous extract of Z.officinale was added to drinking water (100, 200 and 400 mg/100 ml) for 4 days. In another sets of experiments, L-NAME, a nitric oxide synthase inhibitor, (0.1 mg/kg, i.p.) and indomethacin, an inhibitor of the prostaglandin biosynthesis, (2 mg/kg, i.p.) were injected at the day of 5 of implantation. On the 8th day, the mice were killed and the pellets were removed, freed from extraneous tissue and dried at 60 °C for 24h. The increase in the weight of cotton pellets was higher in diabetic mice (control: 160 ± 13.6 mg,diabetic: 271 ± 11.8 mg, P<0.001). Pretreatment with the aqueous extract of Z. officinale caused a significant but not dose-dependent reduction in cotton pellet weight in diabetic animals (diabetic + Z.officinale''s extract: 181.4 ± 21 mg, P<0.05 vs diabetic). The anti-inflammatory effect of extract was almost the same as L-NAME, but less than indomethacin. Results suggest that the anti-inflammatory effects of aqueous extract of Z. officinale are comparable to L-NAME.

Abstract: Positive ventilation has shown to have an influence on pharmacokinetic and disposition of some drugs.Beacause phenytoin with a narrow therapautic range, is the most commonly used drug for prophylaxis and treatment of early seizures after acute brain injuries, in the present study the effect of short term PEEP (5-10 cm H2O for at least 8 hours) on phenytoin serum concentration and pharmacokinetic parameters such as Vmax and clearance in brain injured patients under mechanical ventilation was examined. Ten patients with moderate to severe acute brain injury who were placed on mechanical ventilation with an initial PEEP level of 0-5 cm H2O were included in the study. Patients received phenytoin loading dose of 15 mg/kg followed by a maintenance daily dose of 3-7 mg/kg initiated within 12 hours of loading dose. Sampels were taken on two different occasions before and after PEEP elevation. Total phenytoin serum concentrations were determined by HPLC method. A time invarient Michaelis-Menten pharmacokinetic model was used to calculate Vmax and clearance for each patient.Derrived variables were calculated as follows: Vmax, 3.5-6.8 and 3.7-8.2 mg/kg/day; Clearance, 0.1-0.7 and 0.1-1.2 l/kg/day (before and after PEEP elevation, respectively). Our data have shown a wide range of variability (2.6-32.5 mg/l) in phenytoin serum concentrations. There were no statistically significant differences in the measured total concentrations (p=0.721) and calculated Vmax and clearance (p=0.285)before and after PEEP elevation. Administration of fluid and inotropic agents, limitation in application of higher levels of PEEP and drug interactions, shall be considered as possible explanations for these findings.