Iranian Journal of Basic Medical Sciences
Volume:12 Issue: 1, Spring 2009

Salvia leriifolia Benth. (vernacular names such as Nuruozak and Jobleh) is a perennial herbaceous plant that grows exclusively in south and tropical regions of Khorasan and Semnan provinces, I. R. Iran. Unlike other species of Salvia genus, the chemical constituents of S. leriifolia are not well recognized. The stem oil of the plant consisted mainly both monoterpenes and sesquiterpenes, while in leaf and flower oils monoterpenes predominated over sesquiterpenes. In recent years, the different properties of this plant such as the attenuation of morphine dependence, hypoglycemic, antinociceptive and antiinflammatory, antioxidant, anti-ischemia, anticonvulsant, antiulcer effects, antibacterial activities and antimutagenic effects were evaluated. These effects introduce this plant for more toxicological and clinical trials evaluations as a herbal medicine.

Objective(s)Previous studies have demonstrated that pretreatment with alpha-tocotrienol (α-TCT) can reduce ischemic damage in mice following middle cerebral artery (MCA) occlusion. It is also reported to decrease stroke-dependent brain tissue damage in 12-Lox-deficient mice and spontaneously hypertensive rats. In the present study, the neuroprotective effects of α-TCT and rosiglitazone (RGZ) at 3 hr after cerebral ischemia were investigated. Materials and MethodsStroke was induced by embolizing a preformed clot into the MCA. Rats were assigned to vehicle, α-TCT (1 or 10 mg/kg), RGZ and sham-operation. ResultsCompared to the control group, only RGZ decreased infarct volume (P<0.05), neurological deficits (P<0.05) and sensory impairments (P<0.01) but low and high doses of α-TCT did not show any significant neuroprotective effect. ConclusionOur data showed that α-TCT was not neuroprotective at 3 hr after the embolic model of stroke. Further studies should be undertaken to clarify the neuroprotective effects of α-TCT after stroke.

Objective(s) Staphylococcus aureus is a leading cause of many nosocomial and community acquired infections. According to many reports, antibiotic therapy can not guarantee the eradication of S. aureus infections. Thus designing an adhesin based vaccine could restrain the S. aureus infections. This study designed for construction of a new fusion protein vaccine against S. aureus infections based on adhesin molecules fibronectin binding protein A (FnBPA) and clumping factor A (ClfA). Materials and Methods Bioinformatic experiments were performed using Oligo analyzer and DNAMAN softwares. The fragments corresponding to fnbA binding domain and a C-terminal fragment from clfA were amplified from S. aureus NCTC8325 genomic DNA. Purified PCR products and the vector, pET15b, were digested with NcoI and BamHI. The digested PCR products were hybridized together and then ligated to digested vector. Finally incomplete construct was assembled by Taq DNA polymerase. To quick confirmation of cloning procedure the new construct designated pfnbA-clfA was digested with NcoI and BamHI. To further verification, the product was sent for sequencing. Results The data based on bioinformatic analysis showed no homology between fusion protein and human proteins. Digestion of new vector with NcoI and BamHI confirmed the ligation of fusion protein sequence into pET15b. Sequencing results verified the integrity of target sequences. Conclusion This study is the first effort to construct a new fusion protein vector based on S. aureus adhesins using a new design. This project is being continued to study the expression and biological activity of the fusion protein in a cell culture model.

Objective(s)A sensitive liquid chromatographic method for the analysis of clarithromycin- a macrolide antibiotic- in human serum, using pre-column derivatization with 9-fluorenylmethyl chloroformate (FMOC-Cl) is described. Materials and MethodsThe method involved liquid–liquid extraction of the drug and an internal standard (amantadine) followed by pre-column derivatization of the analytes with FMOC-Cl. A mixture of 0.05 M phosphate buffer containing triethylamine (2 ml/l; pH 3.8) and methanol (17:83, v/v) was used as mobile phase and chromatographic separation was achieved on a Shimpack CLC-ODS column. The eluate was monitored by a fluorescence detector with respective excitation and emission wavelengths of 265 and 315 nm. ResultsThe analytical method was linear over the concentration range of 0.025-10 μg/ml of clarithromycin in human serum with a limit of quantification of 0.025 μg/ml. The assay is sensitive enough to measure drug levels obtained in human single dose studies.ConclusionIn the present method, sensitivity and the running time of analysis have been improved and successfully applied in a bioequivalence study of three different clarithromycin preparations in 12 healthy volunteers.

Objective(s)Developing and validating a simple, efficient, reproducible and economic reversed phase high performance liquid chromatographic (RP-HPLC) method for the quantitative determination of pefloxacin in bulk material, tablets and in human plasma. Materials and MethodsA shim-pack CLC-ODS column and a mobile phase constituting acetonitrile: 0.025 M phosphoric acid solution (13:87 v/v, pH 2.9 adjusted with KOH) were used. The flow rate was 1 ml/min and the analyses performed using ultraviolet (UV) detector at a wavelength of 275 nm using acetaminophen as an internal standard.ResultsThe developed method showed good resolution between pefloxacin and acetaminophen. It was selective to pefloxacin and able to resolve the drug peak from internal standard and from formulation excipients. The percentage of coefficient variation (CV) of the retention times and peak areas of pefloxacin from the six consecutive injections were 0.566% and 0.989%, respectively. The results showed that the peak area responses are linear within the concentration range of 0.125 µg/ml-12 µg/ml (R2= 0.9987). The limits of detection (LOD) and limits of quantitation (LOQ) for pefloxacin were 0.03125 µg/ml and 0.125 µg/ml. The intra-day and inter-day variation, RSD were 0.376-0.9056 and 0.739-0.853 respectively; also, inter-day variation with relative standard deviation (RSD) were 0.1465-0.821 in plasma. The accuracy results of 70%, 100%, and 130% drugs were 100.72%, 100.34%, and 100.09%, respectively.ConclusionThe method is linear, quantitative, reproducible and could be used as a more convenient, efficient and economical method for the trace analysis of drug in biological fluids, in raw material and tablets.

Objective(s)Celecoxib acts through both COX-2-dependent and -independent pathways. According to the paradoxical effect of NO on the inflammatory and nociceptive signal processing, the present study designed to evaluate the probable contribution of NO in the analgesic and anti-inflammatory properties of celecoxib. Materials and MethodsDifferent intensities of inflammatory pain were induced by acute and chronic sc administration of 1%, 2.5%, or 5% formalin and spectrophotometrical analysis of the serum nitrite was performed. Then, in the pretreatment process, the effect of celecoxib (10, 20, or 40 mg/kg/ip) was evaluated on the inflammatory pain induced-nitrite. Also, the effect of celecoxib alone (under non-inflammatory condition) was evaluated on the peripheral NO production and the results compared with that of the vehicle. ResultsFormalin-induced inflammatory pain led to an enhancement of the serum nitrite in intensity- and time-dependent manners. Celecoxib (40 mg/kg/ip), except its ineffectiveness on the nitrite level, induced 1.5 hr after 5% formalin, reduced production of formalin-induced nitrite in other cases. Meanwhile, under non-inflammatory condition, 1.5 hr after the administration of celecoxib (40 mg/kg/ip), a considerable elevation of nitrite was observed. Celecoxib 10 or 20 mg/kg/ip did not show a significant effect on either inhibition or stimulation of the peripheral NO.ConclusionNO is involved both in the inflammatory and non-inflammatory conditions. It seems that celecoxib exerts a dual effect on the peripheral NO production; it prevents overproduction of NO due to the induction of inflammatory pain, while, it stimulates NO synthesis at the early stage of its action.

Objective(s)The aim of this study was to investigate the overall effect of cardiac vasoactive factors during coronary occlusion and reperfusion on peripheral vascular tone, using a sequential isolated rabbit heart-ear perfusion model.Materials and MethodsIsolated ears were perfused with the effluent of isolated hearts subjected to ischemia (30 min) and reperfusion (180 min, n=6). The comparator groups consisted of a sham operated group (no ischemia, n=5) and the ears that were directly perfused with modified Krebs (n=10). At the end of previous experiment, the perfusion mode of the sequentially perfused ears was converted to non-sequential perfusion with modified Krebs for 10 min and vice versa. In a separate experiment, samples collected from heart effluent during different stages of the first experiment were perfused to isolate stabilized ears (3 min; n=5) or hearts (1 min; n=5). The possible effects of the samples on the tone of isolated femoral artery rings were also studied using an organ bath (n=5).ResultsCoronary occlusion and reperfusion did not exert significant effects on the heart rate or the perfusion pressure of the sequentially perfused ears. The samples collected during different stages of ischemia and reperfusion did not affect the vascular tone in isolated ears or femoral artery rings either.ConclusionThe current study suggests that isolated heart, even following ischemia and reperfusion, does not release vasoactive substances in concentrations sufficient enough to affect peripheral resistance.

Objective(s) There are some reports that the teratogenic effects of cyclophosphamide (CPA) can be prevented by application of antioxidant drugs and stimulation of the maternal immune system. Echinacea purpurea extract is antioxidative and immunomodulator drug. Mesna (Sodium 2-mercaptoethane sulfonate) is used for decreasing side effects of CPA, especially hemorrhagic cystitis. In this study, we compared the prophylactic effects of mesna and Echinacea extract on teratogenic effects of CPA. Materials and Methods This study was performed on 32 pregnant rats that were divided into 4 groups. The first group (control group) received normal saline and the other groups received CPA (15 mg/kg intraperitoneally) on 13th day of gestation. Mesna and E. purpurea extracts were administrated at doses of 100 and 400 mg/kg by IP injection, respectively, along with it and 12 hr later, after CPA injection. Rats were dissected on day 20 of gestation, embryos harvested and after determination of gross malformations they were stained by Alizarin red-Alcian blue method. ResultsCleft palate incidence was 38.46, 30.77 and 14.28% in fetuses of rats that received only CPA, CPA with mesna and CPA with Echinacea extract, respectively. In addition, skeletal anomalies incidence including limbs, vertebra, sternum, and scapula defects were decreased by Echinacea extract.ConclusionE. purpurea has significant effect on preventing CPA-induced malformations and better prophylactic effect than mesna on cases like CPA-induced cleft palate.