Iranian Journal of Basic Medical Sciences
Year:2005 | Volume:8 | Issue:4 (28)|Papers Count:12

Objective: Leishmaniasis is a parasitic disease spread by the bite of infected sand flies. Protozoa of the Leishmania species cause leishmaniasis. The protective immunity against leishmaniasis is the cell-mediated immunity (CMI). LmSTI1 is a candidate for the development of vaccine against cutaneous leishmaniasis (CL). Liposomes are microscopic vesicles consisting of phospholipid bilayers which enclose aqueous compartments and are used as an immunoadjuvant. The aim of this study was to formulate liposome preparations containing recombinant rLmSTI1 to induce Th1 response in BALB/c mice against infection with L. major.Materials and Methods: Liposomes containing rLmSTI1 were prepared as dehydration-rehydration vesicles (DRV) and composed of distearoylphosphatidylcholine (DSPC) and cholesterol (CHOL) in a molar ratio of 2:1 (DSPC/CHOL-rLmSTI1). The average size of liposome formulations was 1.1µm checked by light microscope and particle size analyzer. DSPC/CHOL-rLmSTI1 (2µg); soluble rLmSTI1 (2µg); PBS, and a control empty liposome were injected separately subcutaneously (SC) in female BALB/c mice (10 per group), 3 times in three week intervals. The mice were challenged with L. major promastigotes (1.5 X 106) SC to the left footpad and PBS to the right footpad for control at 3 weeks after the last booster. The footpad swellings were measured weekly for 12 weeks. Blood samples were collected on the day before and 12 weeks after challenge to titrate the anti-Leishmania antibodies (IgG total, IgG1 and IgG2a) by ELISA method. The parasite burden in spleen was determined at 15weeks after challenge. Results: The results showed that in the group that received DSPC/CHOL-rLmSTI1, footpad thickness was significantly less; IgG2a titer was higher with very few parasites in the spleen compared to the other groups.Conclusion: The results indicated that encapsulation of rLmSTI1 in liposome seems to be a suitable tool to improve the CMI and rate of protection in murine model of leishmaniasis.

Objective: The study of genetically polymorphism of population have been done on mitochondrial genome in many developed countries. Azeri is one of the largest Iranian ethnic groups settled in north west of Iran. The aim of this study is the evaluation of mtDNA polymorphism by PCR- RELP method.Materials and Methods: In this study 120 blood samples were collected from Azerbaijan people settled in different regions of this state, and the buffy coat of blood samples were isolated. The DNA of white blood cells were extracted, and the mitochondrial D-loop fragment was amplified by using special primers with PCR. Then, PCR product was digested by restriction enzymes.Results: D-Loop Fragment with the size of 1024bp amplified by PCR and related bands showed on gel electrophoresis. In cutting with Hae III enzyme, six diversities were observed, one of which had heteroplasmy. Also, we detected two diversities including one case of heteroplasmy by AluI digestion.Conclusion: Seven genetically diversities were determined in 120 samples. This diversity in our samples can be the result of the extent of a smaller ancestral population or the shorter time genetic history in Azeri ethnic group.

Objective: Cryptosporidium is an important protozoa that cause. diarrheal illness in humans and animals. In immunocompetent individuals, infection is usually self-limiting; but in immunocompromised patients infections which can be life threatening may develop. Cryptosporidium may account for 10 to 20% of the cases of diarrhea in immunocompromised patients living in developed countries and as much as 50% in underprivileged countries.Different strains of Cryptosporidium have been reported, and it is believed that strain characteristics are an important factor to be considered in strategic planning for the control of cryptosporidiosis disease. In this study human and animal isolates of Cryptosporidium oocysts were examined by PCR-RFLP for identifying strain variation in Isfahan.Materials and Methods: A total of 642 fecal samples of children under 5 years of age, imunocompromised patients and high risk persons and 480 rectal specimens of cows and calves were selected randomly in Isfahan. After identification of the samples contaminated with the parasites, oocysts were purified from these samples, and their DNA were extracted. These DNAs were use for detection of Cryptosporidium species using PCR-RFLP analysis of a 1750bp region of 18srRNA.Results: Microscopic results showed that 4.7% of human samples and 6.2% of animal samples were contaminated with Cryptosporidium. 18s rRNA gene of all isolates were amplified by PCR, and 18s rRNA fragment size of all isolates were identical approximately 1750 bp. RFLP results showed that the samples were contaminated with C. parvum II, C. baileyi, C. serpentis, C. muris, C. wrairi and three new genotypes of Cryptosporidium.Conclusion: PCR-RFLP results indicated the occurrence of most strains of Cryptosporidium specially C. parvum. The results also imply extensive polymorphism in these parasites and the occurrence of mutant strains of it. Furthermore, the occurrence of animal species of the parasite in human samples shows the importance of animal-human cycle of it.

Objective: Due to the anti-diabetic effect of Withania somnifera (WS) (ashwagandha) and its beneficial effect on the metabolism of foodstuffs, the hypoglycemic and hypolipidemic effect of this plant was investigated in an experimental model of diabetes mellitus.Materials and Methods: For this purpose, male Wistar rats (n = 48) were randomly divided into 4 groups, i.e. control, WS-treated control, diabetic, and WS-treated diabetic groups. The treatment groups received oral administration of plant-mixed pelleted food (6.25%) for two months. Serum glucose, triglyceride, total cholesterol, LDL- and HDL- cholesterol levels were determined before the study, and at 4thand 8thweeks after the experiment.Results: Serum glucose level in the diabetic group increased 4 and 8 weeks after the experiment as compared to data one week before the study (P<0.001) and WS treatment of diabetic rats had no significant effect. In addition, triglyceride level in the diabetic group increased 8 weeks after the experiment in comparison with related data one week before the study (P<0.05), and there was a significant lower level of triglycerides in W8-treated diabetic rats (P<0.05). Furthermore, a similar significant reduction was obtained for treated-diabetic group as compared to the diabetic group regarding serum cholesterol level (P<0.05). On the other hand, HDL- and LDL cholesterol levels were significantly higher (P<0.05) and lower (p<0.01) in the WS-diabetic group as compared to the untreated diabetic group respectively.Conclusion: Chronic oral administration of WS has no significant hypoglycemic effect and leads to appropriate changes in blood lipid profile.

Objective: Carcinoma of the breast is the most common malignancy in adult women, and attention to it often overshadows that given other breast lesions. Angiogenesis is essential for breast cancer progression and high microvessel density (MVD) within a primary tumor has been associated with stronger likelihood of nodal metastasis and poor prognosis.Materials and Methods: In this study 50 cases of invasive ductal carcinoma of the breast were selected that had been diagnosed and archived in the Pathology Department of Mashhad Ghaem Hospital. Paraffin blocks, were cut and stained for CD34 immunohistochemical marker. Immunohistochemical slides were evaluated for microvascular density in hot spot within the tumoral and normal paratumoral tissue. Correlation between MVD with other parameters such as, age, histologic grade, lymph node involvement and tumoral sizes analyzed by parametric and nonparametric statistical evidence.Results: MVD in normal tissue was adjusted to the tumor, and the ductal carcinoma had significant difference (12.42±2.5 and 46.76±23.4 respectivly).MVD had relative correlation with increased histologic grade (42.3±25.1 for grade I and 63.75±36.5 for grade III).Conclusion: Results of this study shows markedly differences between MVD in normal and tumoral breast tissue, also increase of histological grade have correlation with MVD increment.

Objective: In this research, the effects of treadmill running was studied on the passive avoidance learning and memory (PA) in matured male rats having been morphine dependent.Materials and Methods: In the behavioral stage, 36 rats weighing about 250g were housed in four groups as follows: Control; Morphine dependent; Exerciser and Exerciser's morphine dependent. Intraperitoneal injection (IP) of solved morphine with increased doses of, respectively; first three-day: 10mg/kg, second three-days 20mg/kg and third three-day, 40mg/kg were applied to make rats morphine-dependent. Treadmill running was performed in a ten-day period (two hours a day, at a speed of 12m/min and a incline of 15 degree) for the two groups of exerciser and exerciser's morphine dependent. Passive avoidance learning and memory test after attending physical exercises and making morphine- dependent were performed in similar conditions for all groups.Results: On the basis of these results, in comparision to the average of the Control group with that of the Exerciser and Exerciser's morphine dependent groups; it is confirmed that physical activity strengthen the indicators of positive criterion (LS and Latency) and weaken the negative criterion (DS). About the first indicator (Latency): In the comparison of control group with the two groups of exerciser and exerciser's morphine dependent, a significant increase until 24 hours after footshock, and for the third indicator (LS) until one week after shock and for the second indicator (DS) a significant decrease until one week after shock was observed (***p<0.001, **p<0.01, *p<0.05). In the meantime, no significant difference was observed for one month after shock (p>0.05).In comparison to control group with morphine-dependent group, except for the second indicator (DS) in which a negative criterion was considered, only a significant increase was observed 24 hours after footshock (p<0.05). In comparison to the average of the second group (morphine-dependent) with the fourth group (exerciser's morphine-dependent), it was observed that there is a significant difference for Latency indicator until 24 hours after shock and for the indexicator of LS and DS until one week after footshock (+++p<0.001, ++p<0.01, +p0.05).Conclusion: The result of behavioral steps showed that physical exercises increase the learning rate and strengthen short-term memory (STM) recalling, but it does not have any sensible effect on past event memory. Accordingly, it is said that probably some parts of hippocampus were influenced by physical activity. Moreover, physical exercise had treated the negative effects caused by morphine on the memory and learning in morphine-dependent rats, so that they recalled the past memories in the same way as the control group.

Objective: Dill (Anethum graveolens) from Umbelliferae is used traditionally to treat convulsions and increasing milk production. Also, in Darab (Fars Province) and Yazd dill fruit is used traditionally to prevent abortion. Its antimicrobial, antihyperlipidaemic, anti-hypercholesteroaemic effects and reducing gastric acid secretion have been reported. The aim of the present study was to investigate the effects of dill fruit hydroalcoholic (DFHE) extract on virgin rat uterus contractions induced by KCI (60mM) and oxytocin (10mU/ml).Materials and Methods: Macerated method was used for extract preparation. Virgin Sprague Dawley female rats were pretreated with an injection of estradiol valerate (5mg/kg, s.c.) 24 hours prior to experiment. Rats were killed and uteri were dissected and mounted in an isolated organ bath containing De Jalon solutions (29°C) bubbled by oxygen. Contractile responses were recorded isometrically under 1g initial tension.Results: The DFHE (0.5, 1, 2, 4 and 8mglml) relaxed both KC1- and oxytocin-induced contractions dosedependently (p<0.0001). However, the spasmolytic effect of extract on oxytocin-induced contractions was more potent. In Ca2+-free, rich K+ (120mM) De Jalon solution, cumulative adding of calcium (0.15, 0.3, 0.6, 1.2 and 2.4 mM), increased contractions dose dependently (p<0.0001). DFHE (4 mg/ml) shifted this dose-response curve to the right (p<0.05). In Ca2+ free solution, oxytocin induced strong contractions if calcium (0.3 mM) was added to the bath. However, DFHE (8 mg/ml) reduced calcium-induced contraction (p<0.001). The spasmolytic effect of DFHE was reversible. The spasmolytic effect of DFHE (4 mg/ml) was affected neither by propranolol (1µM) nor by L-NAME (100µM).Conclusion: These results suggest that the relaxatory effect of DFHE on KCI and oxytocin-induced uterus contractions is due, at least in part, to blockade voltage dependent calcium channels and partly by disturbing in releasing calcium from intracellular pool indirectly. In addition, the β-adrenoceptors and NO are not involved in this inhibitory effect of DFHE. Our results may also support the traditionally usage of dill fruit for preventing abortion.

Objective: Surfactin, a crystalline peptide lipid surfactant produced by Bacillus subtilis, inhibits fibrin clot formation. Human Serum Albumin (HSA) is the most abundant protein in the circulatory system. Its principal function is to transport a great variety of metabolites and drugs such as anticoagulants. In the present work, the interaction of HAS with surfactin in solution as a function of concentration is reported.Materials and methods: The structure of HSA at different pH values in the absence and presence of surfactin was investigated by fluorescence and circular dichroism (CD) spectroscopies. The different effects of surf actin upon binding to HSA are interpreted based on considerations of the expected changes in the vicinity of tryptophan residue W214.Results: The results of fluorescence and CD showed that HSA partially unfolded at pH 3.0 and 10.0 in comparison with pH 7.0. At pH 7.0 and 10.0, surf actin at low concentrations caused a red shift of maximum emission and at high concentrations a blue shift of maximum emission, which should mean unfolding after partial folding. But, compare with other pH values (pH 7.0 and 10.0), in pH 3.0, surf actin does not have considerable effect. Stability of HSA obtained at pH 7.0 and 10.0. ΔG (H2O) was about 15 kJmol-1 at pH 7.0 and pH 10.0.Conclusion: Surfactin can denature HSA at very low concentration (0.01 mM). This effect is very similar to synthetic anionic surfactants such as sodium dodecyl sulfate.

Objectives: In this study, the antileishmanial effect of different extracts of Euphorbia myrsinites aerial part was evaluated on promastigotes of Leishmania major in vitro.Materials and Methods: Dried and ground aerial parts of the plant were extracted using either maceration in 80% ethanol or soxhlet in methanol. Then 5 different concentrations of each extract, one positive control, one negative control, and one solvent control were prepared and placed in a 24-well plate containing 40,000 parasites/well. The extract concentrations were 0.06, 0.12, 0.25, 0.5 and 1 mg/ml. Amphotricin B (0.5 mg/ml) was used as positive control while negative control contained only culture medium. The plate was incubated at 25°C for six days, and the amount of parasites in each well was determined on days 2, 4, and 6 of experiment microscopically using Neubar chamber. Results: It was observed that amphotricin B and both macerated and soxhlet extracts at concentration of 1 mg/ml killed all parasites. Lower doses exhibited a dose-dependent antileishmanial activity. The ECso for macerated and soxhlet extracts in DMSO was between 0.5 and 0.25 mg/ml. The control solvents had no significant effect on the L. major promastigotes.Conclusion: These results indicated that both macerated and soxhlet extracts of E. myrsinites have favorable leishmanicidal activity.