Iranian Journal of Basic Medical Sciences
Year:2003 | Volume:6 | Issue:3 (19)|Papers Count:10

A study was performed in order to investigate the efficacy of simple disinfecting procedure for three Allium species (A. sativum, A cepa, A. Ascalonicum) on giardia cysts. The cysts were obtained from stools of individuals with Giardia intestinalis infection using a modified sucrose gradient procedure. A pool batch of Giardia cyst containing 3× 104/ ml Giardia cysts was prepared from all specimens. The cysts were kept at 4°c until use. Before each experiment, the numbers of cysts were determined by a hemocytometer. Two Sets of eppendorf tubes were used for the experiments. One set in 4°C and another in 24°C  in each tube 100µl of each extract of the plants were poured and 100 µl of Giardia cysts for pooled specimen eppendorf tubes. Variables were disinfectant materials, temperature and time of exposure. The viability of cysts was determined using eosin inclusion procedure. The viability of at least 250 cysts in each tube at the times of 0, 0.5, 1, 2 and 3 hours after the beginning of experiments were determined. The mean giardiacidal activity at 4°C for the A. sativum, A. ascalonium and A. cepa after 3 hours was 36.00%, 28.46%, 33.26%, and at 24°C was 43%, 33.86%, 41.13% respectively. In conclusion the giardiacidal activity of A. sativum is more than other species. The highest giardiacidal activity of A. sativum was 24°C temperature and after three hours.      

This study was designed to evaluate the usefulness of argyrophilic nucleolar organizer region protein (AgNOR) staining in differentiation of reactive mesothelial from malignant cells in serous effusions. AgNOR dots were counted in the 66 cytologic samples, randomly for the study, and divided as follow: 50 samples from patients having benign cytology and 16 samples from patients with malignant cells. The investigated parameters were mean number of AgNOR dots in nuclei of hundred cells and percentage of nuclei having 1, 2, 3, 4, 5 or more AgNOR dots per cell. The means AgNOR count was significantly higher in the malignant cells than reactive mesothelial cells. The AgNOR staining is an easy and inexpensive method to differentiate reactive mesothelial from malignant cells in effusion fluids.      

Interleukine-4 (IL-4) is one of the most important cytokine that secreted by T Iymphocytes. This molecule has variety of effects on hematopoietic cells, especially cells that involve in immune system. IL- 4 gene cloned in various expression vectors such as E.Coli, Yeast and recently mammalian cells. By those ways IL-4 can be expressed and then purified. There is no documented report about the expression of hIL-4 cDNA in mamalian cell line like CHO cell line. In this study CHO (Chinese Hamster Ovary cells) which had been transfected with IL-4 gene was used as an expression vector. For this purpose, anti-IL-4 monoclonal antibody was prepared by specific hybridoma. For antibody and rIL-4 recovery, cell culture techniques had been set up. For this purpose, frozen hIL-4 cDNA transfected and hybridoma cells were thawed and cultured. Culture supernatant was collected. This supernatant of hybridoma cell culture was processed for antibody recovery by protein A Sepharose and purified antibody was attached to activated Sepharose gel as a ligand for affinity chromatography. Then affinity chromatography method used for rIL-4 purification from CHO cell culture supernatant. Purified sample was evaluated by SDS-PAGE. By this method one band with molecular weight of about 27KD was appeared. This band was transferred to nitrocellulose membrane and blotted by anti-IL-4 antibody and labeled by HRP conjugated anti-mouse antibody to confirm antigen-antibody complex formation in membrane. Based on our Results, affinity chromatography is the most simple and efficient method for IL-4 purification from culture supernatant contains protein.      

We have previously showed that thymoquinone, the major component of Nigella sativa seeds, exhibits anticonvulsant effect. In this study, we investigated the mechanism of anticonvulsant activity of thymoquinone. As there is some reports indicate the interaction of thymoquinone with opioid receptors, we evaluated the probable involvement of naloxone, a competitive opioid receptor antagonist, in the anticonvulsant effect of thymoquinone. In pentylenetetrazole test, naloxone (0.3 mg/Kg, ip) inhibited not only the prolongation of the onset but also the reduction of the duration of seizures, which both induced by thymoquinone (40, 80 mg/kg, ip). we concluded that thymoquinone exerts its anticonvulsant activity through the stimulation of opioid receptors in the central nervous system.      

In this study, we investigated power of learning and memory in two-month old male wistar rats whose mothers were given orally aqueous extract of the gum resin of Boswellia serrata (0. 1g/kg/day) the during lactation period (3 weeks), according to active avoidance learning test. Results showed that there is a significant increase of power of learning at pre-learning stage (p<0.003), and post-learning stage (p<0.027). It also showed significant increase in short-term memory (p=0.000) and long- term memory (p=0.000) in experimental group as compared to control group.    

In preliminary experiments, the production of biosurfactant by three Bacillus subtilis strains was investigated. The hemolytic and foam forming activities of the supernatant of different strains cultured in nutrient broth were studied and consequently, Bacillus subtilis ATCC6633 was selected as the suitable strain. Bacillus subtilis ATCC6633 was grown in nutrient broth medium and biosurfactant production was evaluated every 24 h by surface tension and emulsification index. The selected strain was grown in different media in order to get maximum production ofbiosurfactant. The best culture medium was found to be Brain Heart Infusion Broth medium (BHIB) supplemented with Fe2+and Mn2+. After growing the bacteria in that culture medium, the microbial biomass was removed by centrifugation. Biosurfactant was extracted from the supernatant by methods including acidic precipitation, extraction by dichloromethane and recrystallization. However, yield was improved by the addition of iron and/or manganese salts to the culture medium. The critical micelle concentration (CMC) and erythrocyte hemolytic capacity of the biosurfactant were compared to those of surfactants such as SDS (sodium dodecyl sulphate), BC (benzalkonium chloride), TTAB (tetradecyltrimethylammonium bromide) and HTAB (hexadecyltrimethylammonium bromide). The maximum hemolytic effect for all surfactants was observed at concentrations above CMC.The maximum hemolytic effect of synthetic surfactants was more than that of the biosurfactant produced by B. subtilis ATCC6633. Therefore, biosurfactant would be considered as a suitable surface-active agent due to low toxicity to the membrane.      

Oligodeoxynucleotides (ODN) having a CpG motif (CpG-ODN) are regarded as a new class of potent immunoadjuvants. It has been shown that concomitant delivery of an antigen with CpG-ODN to the same APC will be able to increase the immune responses against the relevant antigen. The main objective of the present study was co-encapsulation of tetanus toxoid (TT) and CpG-ODN in PLGA microspheres and evaluation of immune responses gained by the concomitant delivery of TT and CpG-ODN via the same delivery system. Both TT alone and [TT+CpG-ODN] were encapsulated in PLGA microspheres. The following groups of mice were immunized twice 2 Lf TT in the presence or absence of 4µg CpG-ODN via subcutaneous route: 1) encapsulated [TT + CpG-ODN]; 2) encapsulated TT alone; 3) encapsulated TT with CpG-ODN solution; 4) solution of [TT+ CpG-ODN]; 5) alum adsorbed TT (routine vaccine). Mice immunized with microspheres encapsulated with [TT+CpG-ODN] showed a very high T cell proliferation (stimulation index=45 in T cell proliferation assay and very high levels of INF-γ (2694.7±41.1 pg/ml) which was significantly higher than those of other groups. Anti-sera obtained from this group also showed very high total IgG titers (end point titers 2560000) which was 16 times that of the group immunized with the solution of [TT+CpG-ODN]. Also the titers of IgGl, IgG3 and IgG2b obtained from group 1 were considerably higher than those from other groups. Interestingly however the IgG titers induced in group 5 were far less than that in group 1 (total IgG, end point titers 160000). This study clearly showed that [TT+CpG-ODN] encapsulated in PLGA microspheres was more efficient than the relevant solution in terms of inducing immune responses. Also the results indicated that the co-delivery of TT and CpG-ODN in PLGA microspheres elicits a stronger Th1 (i.e. IgG2b, IgG3, INF- γ ) as well as Th2 (i.e. IgG1) type responses.        

RF receive and transmit non-homogeneity is one of the most effective causes of image non-uniformity in MRI images and is considered as an important source of error in quantitative studies. Part of this non-homogeneity is a characteristic of RF coils and part of it, is due to the interaction of RF field with the body being imaged. In this study, RF field non-homogeneity of a volume head coil is measured in human brain (In vivo) as well as in water and oil phantoms, using a method which was proposed by this group formerly. Comparing the results shows that RF non-homogeneity in water phantom is more than its value in oil phantom. It was also shown that it was even more than its value in human brain In vivo conditions. Non uniformity pattern shows that in both In vivo and water phantom cases, standing wave effect is dominant under our experimental conditions which may cause over-estimating in real magnitudes of Rf non-homogeneity and imaging effective parameters, such that, should has been considered in designing of MRI related phantoms.      

Carbohydrate chains glycoconjugates on the cell surface and extracellular matrix, particular terminal sugar, have critical role(s) in many biological functions. One terminal sugar is sialic acid, a large carbohydrate with different chemical properties. There has been little attention to distribution of these molecules in the enteric nervous system as well as other parts of the gut mall. Five paraffin section were incubated with a lectin from triticum vulgaris (WGA) in order to identify distribution of sialic acid and to some extent, N-acetylglucosamine in the adult elementary mall. Our data shows strong reaction on the enteric nervous system of the gut myenteric (Auerbach) plexus, colon crypts particularly. Their basal cell surface is stained also with this lectin. Sialic acid might facilate cell interactions between those reacted areas with their microenvironents, and as it has been well documented, these molecules may change with advanced aging and or in pathological conditions. Highly negatively charged, produced by sialic acids, they also provide biological areas for suitable molecule interaction during enteric nervous system function. Further investigation of other glycoconjugates will be carried on in the near future.    

Entamoeba dispar is a commensal and non-pathogenic amoeba occurring in the large intestine of the human. E.dispar is identical to pathogenic Entamoeba histolytica with regards to morphology. Laboratory diagnosis of it from E.histolytica, the causative agent of human amoebiasis, is important in both clinically and epidemiological studies. Sixty sera from individual infected with E.dispar and 32 sera from healthy persons were collected and tested by using IFA for antibody to amoebiasis. All sera (100%) of healthy individual and 30(96.7%) of individual infected with E. dispar found to be contained antibodies to amoebiasis in1: 40 and lower rates. The mean rate of antibody in both control and study groups were lower than 1: 10 and were not significantly different by χ2 statistical analysis. This results show that in E.dispar cyst passer and healthy persons the mean level of antibody is similar and very lower than diagnostic titer valuable for diagnosis of amoebiasis.