Cell Journal (Yakhteh)
Year:2004 | Volume:5 | Issue:20|Papers Count:8

Introduction: The immunogenicity of crude amoebic antigen and its fractions prepared from Entamoeba histolytica (NIH: 200) was evaluated in experimental animals.Materials and Methods: Forty two guinea pigs of either sex free from Entamoeba infection and aged around 3 to 4 weeks were randomly divided into 5 groups. The treated groups consisted of 8, 10, 6 and 8 animals served as controls. Crude amoebic extract and its chromatographed fractions were used to immunize the treated animals. All the animals were assessed for immunity status, challenged with Entamoeba trophozoites and subsequently examined for lesions of the caecum and liver.Results: Of the 8 animals immunized with crude antigen, one had liver abscess and 5 had caecal lesions. None of the 10 animals immunized with fractions I (FI) had hepatic lesions and one had caecal lesions. Both caecal and hepatic lesions were observed in animals immunized with FII & FIII.Conclusion: Results show that vaccination with the F1 fraction of Entamoeba histolytica provided up to 90% protection against infection. The other fractions and the crude extract provided less protection.

Introduction: This paper presents the results of a study on the effects of two different doses of low - power laser irradiation on healing of deep second degree burns. Material and Methods: 60 rats were randomly allocated to one of four groups. A deep second - degree burn was inflicted in each rat. In the control group (CG) burns remained untreated; in groups LG1 and LG2 the burns were irradiated with low - power Helium Neon laser with energy densities of 1.2 J/cm2 and 2.4J/cm2 respectively. In the fourth group (G4) the burns were treated topically with 0.2% nitrofurazone cream. The response to treatments was assessed histologically at 7, 16 and 30 days after burning and microbiologically at Day 15. Results: The number of macrophages and the depth of new epidermis was significantly less in the laser treated groups compared to control and nitrofurazone treated groups. Staphylococcus epidermidis was found in the wounds of all rats in the laser treated groups. Conclusion: Irradiation of deep second - degree burn with low - power laser produced no beneficial effects on healing of burns.

Introduction: The aim of this study was to evaluate the expression of pinopodes as an implantation marker after ovarian hyperstimulation and progesterone injection using scanning electron microscope studies.Material and Methods: Three groups of NMRI adult female mice were used in the experiment. The control group (Group A) was untreated pseudopregnant mice. Group B mice were made pseudopregnant after superovulation treatment with hMG. Group C mice were treated the same as Group B and then received progesterone daily from day 1 of pseudo pregnancy. Animals were sacrificed by cervical dislocation 3.5 and 4.5 days after hCG injection. Tissues were obtained from the middle 1/3 part of uterine horns and processed for scanning electron microscopic studies.Results: In the control group there were some pinopodes at 3.5 days of pseudopregnancy and the apical surface of all cells expressed these projections on day four. In the hyperstimulated group without progesterone injection no pinopodes were seen 3.5 days after hCG injection and some appeared on day 4. In the hyperstimulated and progesterone - injected group well developed pinopodes were expressed 3.5 days after stimulation and they became much smaller on day 4 after hCG injection.Conclusion: The results showed that the life span of pinopodes is short and changeable during hyperstimulation and that progesterone causes premature expression of the pinopodes, suggesting that the implantation after ovarian stimulation might depend upon the timing of the pinopodes expression.

Introduction: Laser pointers are devices that produce a weak laser beam of 630 - 680 nm wavelength and 1-5 m W power (Class II or III A laser). These devices generally emit a red beam that is used by lecturers and teachers for presentations. Some children use pointers as toys and sometimes direct the beam to their own or others" eyes.Material and Methods: Following irradiation by a laser pointer beam for 8 seconds the eyes of Chinchilla rabbits were examined by opthalmoscope, and fluorescein angiography was performed 5 , 10 and 15 min after the exposure. The rabbits were killed immediately or 24 h after exposure, the eyes were enucleated, and the histological features of sections from fundus, retina and choroid were observed by transmission electron microscopy.Results: A fluorescein block was found in the irradiated area immediately after irradiation and it increased in size with increasing time after exposure. The ultrastructural study showed acute edema shortly after exposure and thick collagenic bundles after 24h.Conclusion: Laser pointers with labelled power of less than 1 m W are capable of producing visible and ultrastructual lesions in pigmented rabbit eyes.

Introduction: Certain types of human papillomavrus (HPV) are associated with cervical intraepithelial neoplasia (CIN) and squamous cell carcinoma (SCC). The aim of the observations reported here was to determine whether the prognosis for invasive cancers of the uterine cervix is related to the type of human papillomavirus associated with the tumor.Material and Methods: Twenty Patients with invasive cervical cancer were prospectively registered from 2000 to 2001. HPV typing was performed by insitu hybridization (ISH) on DNA extracted from frozen, formalin - fixed, paraffin - embedded tumor specimens. The specimens mostly represented classifications SCC Stage 1 and Stage 2 of the International Federation of Gynecology and Obstetrics (Table 1). HPV - DNA was detected by insitu hybridization, using three different DNA Probes: types 6/11, 16/18 and 31/33/51.Results: HPV - DNA was detected in the nuclei of SCC tumor cells in 13 (65%) of 20 cases. Of the 13 HPV - DNA positive cases three reacted only with the HPV 31/33/51 and 6/11 probes, four showed 6/11 and 16/18 genotypes and one case reacted with 31/33/51, 6/11 and 16/18 probes.Conclusion: The prognosis for invasive cancers of the uterine cervix is dependent on the oncogenic potential of the associated HPV type. HPV typing may provide a prognostic indicator for individual patients and is of potential use in defining specific therapies against HPV harboring tumor cells. These finding are consistent with the hypothesis that HPV infection is the primary cause of cervical neoplasia. Furthermore, they support HPV vaccine research to prevent cervical cancer and efforts to develop HPV - DNA diagnostic tests.

Introduction: Lactic acid bacteria are widely used for the fermentation and preservation of dairy and meat products and to improve their aroma and texture. The aim of this study was to screen lactobacillus plantarum isolated from sausage for detections of plasmids, protein bands and phages, to find possible linkage of bacteriocin production to genetic location.Material and Methods: Two Lactobacillus plantarum with antibacterial activity were isolated from sausage. Bacterial plasmids were isolated by alkali lysis and electrophoresis through agarose gel. Proteins were precipitated from cell - free supernatants by ammonium sulphate and analysed by SDS - PAGE. For detection of phages, mitomycin C of final concentration of 2.5  mg/ml was used and phages were detected by transmission electron microscopy.Results: One plasmid of about 4.5 kbp was detected in one Lactobacillus plantarum strain. Two bands of proteins were found on SDS - PAGE. The molecular weight of protein bands of Lacto. Plantarum without plasmid was higher than the protein bands of Lacto. Plantarum with plasmid. A phage was detected on the cell wall of one strain of Lacto. Plantarum; no plasmid was detected in this Lacto. Plantarum. It appears that antibacterial activity is located in the phage of this strain.Conclusion: the high molecular weigh of proteins with a wide spectrum effect on bacteria may indicate chromosome - coded bacteriocin. The role of phages in lactobacilli could be a factory which inhibit meat product starter cultures or attributed in antimicrobial activity, i.e. antibacterial genes might be on chromosomal phages. Bacteriophages could be a threat to industrial fermentation foods.

Introduction: Bleomycin sulfate is a DNA damaging agent used in cancer chemotherapy. The effect of this drug on various cell cycle stages might be different, thus inducing different modes of death (apoptotic or mitotic death). The aim of this investigation was to study the effects of bleomycin on human peripheral blood lymphocytes at various cell cycle stages by two different end points (induction of apoptosis or micronuclei). Material and Methods: Human peripheral blood lymphocytes were treated with various doses of bleomycin at G0, G1, and G2 phases of the cell cycle and the percentages of apoptosis (AP) and micronuclei (MN) were determined. The peripheral lymphocytes were isolated by ficoll hypaque and suspended in RPMI - 1640 containing 15% fetal calf serum. The isolated lymphocytes were stimulated by phytohemagglutinin (PHA), cultured again in RPMI - 1640, harvested after 64 hrs and 96 hrs, and stained with acridine orange and ethidium bromide to determine the percentage of apoptotic cells. MN assay was done according to the standard in vitro micronucleus assay.Results: The results showed that the percentages of apoptotic cells and MN at G2 stage were significantly higher than those of G0 and G1 stages. At higher doses, MN formation and apoptotic cells were increased; however with increasing time, the percentage of MN decreased while the percentage of apoptotic cells generally increased in all the cell cycle stages.Conclusion: The results indicate that bleomycin is a potent inducer of both micronuclei and apoptosis. The incidence of apoptotic cells following bleomycin treatment in G0 and G1 was much higher than the incidence of micronucleated cells at the two sampling times. The percentage of AP cells following bleomycin treatment remained constant across cell cycle stages.

Introduction: Lead is one of the heavy metals that have adverse effects on blood cells and hemopoiesis. In this study the ultrastructure of neutrophils in fetal rat spleen were investigated following lead intoxication. Material ad Methods: Thirty female and 6 male Sprague - Dawley rats were chosen by simple random sampling. After mating the pregnant rats were classified into test and control groups. From the first day of pregnancy the test group was provided ad lib with water containing 0.13% lead acetate and the control group had access to distilled water. After birth 10 newborn in each group were chosen by systematic random sampling. The spleens of the newborn rats were fixed in a solution of 2% glutaraldehyde, and after processing, sections were studied by a transmission electron microscope.Results: The ultrastructural changes included: irregular nuclei with deep invagination, plasma membrane pockets, presence of vacuoles with a heterogeneous material and an increasing incidence of rough endoplasmic reticulum with dilated cisternae. No differences between the groups were observed in the mitochondrial morphology and pattern of cytoplasmic granules (primary granules with electron dense appearance and specific or secondary granules with less electron density and heterogeneous appearance).Conclusion: Lead transmitted via the placenta can affect the ultrastructure, and most probably the function, of fetal neutrophils. More attention must be given to the dangers of lead pollution of the environment and the need to eliminate exposure to lead in work places.