Iranian Journal of Basic Medical Sciences
Volume:14 Issue: 5, Sep-Oct 2011

Objective(s)Crocin bleaching assay (CBA) is a new method for determination of antioxidant capacity. In CBA, addition of hydrogen to the conjugated double bonds of crocin results in reduction of crocin and increase in the absorbance at 440 nm, which is considered as a measure of antioxidant potential. Here CBA method was set up using di-gentiobiosyl crocin or α-crocin from Iranian saffron. Then, the antioxidant activity of some known antioxidants i.e. L-ascorbic acid, bilirubin, Trolox, uric acid, and some plasma samples of infants, were tested. The results were compared to that obtained by ferric reducing antioxidant power" (FRAP) as a standard method.Materials and MethodsDi-gentiobiosyl crocin was extracted and purified from Iranian saffron as previously described by us. Then, the CBA procedure using α-crocin was done in 2 different aquatic conditions, >50% or >90% of water. Results were analyzed by both the Bors method (calculating the relative rate constants= Krel) and the Tsimidou method (calculating the percent of a-crocin bleaching inhibition=% Inh).ResultsOur results indicated the following order of antioxidant potential for the above mentioned agents: ascorbic acid > uric acid > Trolox. However, these results are very similar to the data reported by others, but they are strongly related to the aqueous condition. In addition, uric acid showed different properties at different concentrations; so that it showed the antioxidant activity at low concentrations but it acted as a prooxidant at higher concentrations. Bilirubin interfered with this test, possibly because its maximum absorbance is close to the crocin. The obtained data for the antioxidant capacity of the serums was comparable with FRAP assay, except for the sample that contains high bilirubin concentration.ConclusionIn conclusion, it seems that CBA using the main fraction of crocin (a-crocin) is a simple and useful method for determination of antioxidant potential of aqueous samples. In addition, the CBA ability to distinguish the samples that contain bilirubin or high uric acid content is helpful in clinical laboratories.

Objective(s)Leishmania can lead to a broad spectrum of diseases, collectively known as leishmaniasis. The A2 gene/ protein family could be one of the most eligible candidate factors of virulence in visceral leishmaniasis (VL). The previous results confirmed that in Leishmania infantum, several A2 proteins are abundantly expressed by the amastigote, but not the promastigote stage. As there are no data available on the pattern of A2 gene / protein in Iranian Leishmania isolates of either cutaneous leishmaniasis (CL) or VL; the current study aimed to investigate molecular analysis of A2 gene in leishmania species among field isolates of Iran.Materials and MethodsAn A2 gene was identified by sequencing of crude PCR products resulting from 20 samples of CL and 10 samples of VL isolates from Iranian patients. ResultsThe results indicated the A2 gene in CL is only a single copy of 153 bp encoding a protein of 51 amino acids, as opposed to A2 of VL species with multi-copy genes of varying length. A2 sequences in Iranian L. major strains represented a homology with stage-specific S antigen-like protein (A2) of L. major and L. infantum. Moreover, A2 sequences in Iranian L. tropica strains have homology with A2 protein of L. major and L. tropica. ConclusionIt is concluded that A2 is an antigen candidate for vaccine development and diagnosis purposes and that A2 sequences are conserved among field isolates.

Objective(s) The mechanism(s) by which antidepressants regulate the hypothalamic-pituitary-adrenal (HPA) axis remain elusive. The endocannabinoid system (eCBs) which exhibits antidepressant potential, appears to regulate the HPA axis activity. Therefore, we aimed to investigate the role of the eCBs in the action of doxepin including its effect on the HPA axis. Materials and MethodsMale Wistar ratsreceived acute and four-week intraperitoneal injections of doxepin (3, 5, and 10 mg/kg) or its vehicle (0.9% saline). One hr after the last injection, animals were exposed to a 5 min swim stress session. In other cohorts of animals, the CB1 receptor antagonist AM251 (0.25, 0.5, and 1mg/kg) was injected 30 min before the administration of doxepin. Plasma corticosterone concentration was measured by enzyme-immunoassay at 45 min following stressing. 1, 5, and 12 hr after the last injection of doxepin, the contents of endocacannabinoids (anandamide and 2-arachidonylglycerol) within the lipid extracts of the prefrontal cortex, amygdala, hippocampus, and hypothalamus were determined using isotope-dilution liquid chromatography-mass spectrometry. ResultsChronic treatment with doxepin (10 mg/kg) significantly reduced the secretion of corticosterone due to 5 min exposure to swim stress. Acute administration of doxepin evoked no effect. Pre-application of AM251 (1 mg/kg) abolished the ability of doxepin to reduce corticosterone secretion. Chronic administration of doxepin (10 mg/kg) led to a significant elevation of the endocannabinoids in the examined brain regions. ConclusionIt appears that doxepin exerts its effects, at least in part, through activation of the eCBs and the CB1 cannabinoid receptors play a major role in this regard.

Objective(s)Aristolochia indica has been widely used in the traditional medicine for the treatment of a variety of diseases. In the present study different extracts of rootsofA. indica were evaluated for their anti-inflammatory, antipruritic and mast cell stabilizing activity. Materials and MethodsAnti-inflammatory activity was performed by compound 48/80 induced rat paw edema model and antipruritic activity by examining the incidence of scratching behavior. Mast cell stabilizing activity was performed by compound 48/80 and sheep serum induced mast cell degranulation methods.Results The ethanol extract (300 mg/kg) and petroleum ether extract (100 mg/kg) were found to inhibit mast cell degranulation significantly equivalent to that of standard drug ketotifen (69%) by compound 48/80 model. In sheep serum model the ethanol extracts (150 and 300 mg/kg) and petroleum ether extract (100 mg/kg) showed good mast cell stabilizing activity (66-67%). Ethanol extract at 150 mg/kg showed 70% reduction of rat paw oedema and also significantly reduced the scratching response. ConclusionResults suggest A. indica has good mast cell stabilizing, anti-inflammatory and antipruritic activity.

Objective(s) Seed ofCucumis sativus Linn. is one of the herbal remedies has been traditionally used for diabetes mellitus treatment. We studied the effect of hydroalcoholic and buthanolic extract obtained from C. sativus seeds in a model of streptozotocin (STZ)-induced diabetic (type I) rats.Materials and MethodsNormal and diabetic male Wistar rats (STZ, 60 mg/kg, intraperitoneal) were treated daily with vehicle (5 ml/kg), hydroalcoholic (0.2, 0.4, 0.8 g/kg) and buthanolic extract (0.2, 0.4, 0.8 g/kg) and glibenclamide (1 & 3 mg/kg) separately and treatment was continued for 9 days. Blood samples were taken at 0, 1, 2, 3, 4, 8 hr of the first day and the day 9 (216 hr) of treatments for measuring the blood glucose levels.ResultsOur findings indicated that C. sativus seeds extracts were not effective on reducing blood glucose levels (BGL) in normal and diabetic rats for initial phase of treatments. However, both hydroalcoholic (22.5-33.8 %) and buthanolic (26.6- 45.0 %) extracts were effective on diminishing BGL and controling the loss of body weight in diabetic rats compared to controls after 9 days of continued daily therapy. Glibenclamide on the other hand, had hypoglycemic action in normal (27.8-31.0 %) and diabetic rats (36.0-50.0 %) after acute and prolonged treatments.ConclusionIt is concluded that C. sativus seeds extracts (hydroalcoholic and buthanolic) had a role in diabetes control probably through a mechanism similar to euglycemic agents. Further studies are warranted to clarify the mechanisms and the exact role of this herbal medicine in control of metabolic disorders.

Objective(s)To compare two identification methods, i.e., restriction fragment length polymorphism (RFLP)-PCR analysis and enzymatic method Rapid TM Yeast Plus System to identify different species causing vulvovaginal candidiasis (VVC).Materials and MethodsVaginal discharges of women who had attended the gynecology outpatient clinic of Mobini Hospital in Sabzevar, Iran were collected using cotton swabs and were cultured on Sabouraud dextrose agar. Isolated yeasts were identified by germ-tube testing and Rapid TM Yeast Plus System (Remel USA). For molecular identification, the isolated DNA was amplified with ITS1 and ITS4 universal primers and PCR products digested with the enzymeHpaІІ followed by agarose gel electrophoresis. Epidemiological and clinical features of women with respect to identified species were also evaluated.ResultsOut of 231 subjects enrolled, 62 VVC cases were detected. The isolated species were identified as follows: Candida albicans, 24 (38.7%), C. glabrata, 15 (24.2%), C. kefyr, 13 (21.0%) C. krusei, 9 (14.5%), and Saccharomyces cerevisiae, 1 (1.6%) by RFLP-PCR method; whereas findings by Rapid TM Yeast Plus System were C. albicans, 24 (38.7%), C. glabrata, 5 (8%), C. kefyr, 11 (17.7%) C. krusei, 2 (3.2%), S. cerevisiae, 9 (14.5%), and C.tropicalis, 6 (9.6%) as well as other nonpathogenic yeasts, 4 (6.9%).ConclusionStatistical comparison showed that there is no significant difference in identification of C. albicans by the two methods; although, in this study, it was not true about other species of yeasts. A correlation between clinical and laboratory findings is important as it enables us to administer an appropriate treatment on time.

Objective(s)Calcium-channel blockers have an important role in the treatment of several cardiovascular disorders. Derivatives of 1, 4-dihydropyridine are one of the most potent calcium antagonists. In this study four novel 1, 4-dihydropyridine calcium channel blockers were synthesized and their hypotensive properties were investigated in male rats.Materials and MethodsFour 1, 4-dihydropyridines bearing 1-(4-fluorobenzyl)-5-imidazolyl substituent at 4 position (5a-d) were synthesized and tested for hypotensive activity in male rats. The animal was anaesthetized and the right jugular vein was cannulated for the administration of test agents. The left carotid artery was cannulated and connected to a pressure transducer for continuous monitoring of arterial blood pressure.Results All synthesized compounds lowered rat blood pressure significantly in comparison with DMSO as vehicle and nifedipine as positive control. The hypotensive effects of all compounds were less than that of nifedipine at 2 and 4 mg/kg (P< 0.05). The order of their effects on mean arterial blood pressure (MABP) was 5b>5c>5a>5d at dose of 4 mg/kg (P< 0.05). All compounds tested increased heart rate in comparison with DMSO (P< 0.05). The chronotropic effect of nifedipine was significantly less than synthesized compounds at dose of 4 mg/kg (P< 0.01).ConclusionThe results showed that these novels 1, 4-dihydropyridines decreased mean arterial blood pressure (MABP) significantly, while increased heart rate in rat.

Objective(s)Extensive use of quinolones has been associated with raising level of resistance. In the current, we focused on assessing the prevalence of Escherichia coli resistance to quinolones and frequency of qnrA, qnrB and qnrS in non ESBLs (extended spectrum beta-lactamases) and ESBLs producing E. coli with blaSHV and blaTEM.Materials and MethodsOne hundred and fiftyE. coli isolates were identified during Mar. 2007 to Apr. 2008 in Milad (Tehran) hospital. They were tested for ESBLs production as well as quinolone resistance. PCR was performed for detection of blaSHV and blaTEM as well as qnrA, B and S. ResultsOf 150 isolates, forty-two (28%) ESBLs producing and one hundred and eight (72%) non-ESBLs producing E. coli were identified. 64.2% (n= 24) of E. coli producing ESBLs and 4.62% (n= 5) of non-ESBLs E. coli were resistance to ciprofloxacin. 95.2% (n= 40) and 26.1% (n= 11) of the isolates harbored blaTEM and blaSHV, respectively. 23.8% (n= 10) had both genes. 37.5% (n= 9) and 20.8% (n= 4) of ESBLs producing E. coli were positive for qnrA and qnrB respectively. qnrS was not identified in any isolate. ConclusionOur study showed high frequency of ESBLs producing E. coli as well as quinolone resistance genes (qnrA, qnrB) in Milad hospital.

Objective(s)The objective of this study was to document and explain bilateral differences in the Q angle. Materials and MethodsTwo hundred limbs of healthy adult Indian volunteers were studied. The Q angle was measured using a goniometric method with the subjects supine, quadriceps relaxed and lower limbs in neutral rotation. The relative lateral placement of the tibial tuberosity with respect to the centre of the patella was measured. Appropriate statistical tests were used to determine the bilateral variability in the Q angle and the lateral placement of the tibial tuberosity. Inter-observer variation of the above mentioned parameters were studied in twenty limbs.ResultsThe average Q angle value of all the 200 limbs was 12.73 °C;the mean value on the right was 12.86 °Cand 12.60°Con the left. When the Q angle and the lateral placement of the tibial tuberosity were considered in pairs a significant difference was noted in males. The Q angle value on the right side was more often greater than the left. The relative lateral placement of the tibial tuberosity showed a significant positive correlation with the Q angle. The intra-class correlation coefficient was 0.66 for the Q angle and 0.8 for the lateral placement of the tibial tuberosity.ConclusionThe present study shows that bilateral variability in the Q angle could be attributed to an alteration of the relative placement of the tibial tuberosity with respect to the centre of the patella.

Objective(s)Urtica dioica L. has been known as a medicinal plant in the world. This study was conducted to determine the effects of the hydroalcoholic extract of Urtica dioica leaves on seminiferous tubules of diabetic rats.Materials and MethodsAnimals were allocated to control, diabetic and protective groups. Treated animals received extract of U. dioica (100 mg/ kg/ day) IP for the first 5 days and STZ injection on the 6th day. After 5 weeks, testes removed and stained with H&E technique.ResultsTubular cell disintegration, sertoli and spermatogonia cell vacuolization, and decrease in sperm concentration observed in diabetic in comparison with control and protective groups. External seminiferous tubular diameter and seminiferous epithelial height significantly reduced (P< 0.05) in diabetic compared with controls, and these parameters increased (P< 0.05) in the treated compared with diabetics. ConclusionHydroalcoholic extract of U. dioica, before induction of diabetes; has protective role onseminiferous tubules alterations.

Objective(s) This study planned to assess antidepressant like activity of aqueous extract from leaves of Citrus maxima Merr. (Rutaceae).Materials and MethodsBoiling was used for aqueous extraction. Acute toxicity study was performed in mice. Antidepressant activity was studied using locomotor activity test, modified forced swimming test (FST) and tail suspension test (TST). Three doses 100, 200 and 300 mg/kg of aqueous extract of leaves were selected for testing. Fluoxetine (20 mg/kg, i.p.) and imipramine (30 mg/kg, i.p.) were used as the standard drugs. ResultsAqueous extract of Citrus maxima leaves significantly reduced immobility time in both TST and FST. In locomotor activity testing it showed psychostimulant effect. Extract increased the climbing behavior in FST, which is similar to effect observed with imipramine. ConclusionThe results of this study suggest that antidepressant like effect of Citrus maxima seems to be mediated by an increase in norepinephrine level in synapses.