Cell Journal (Yakhteh)
Year:2002 | Volume:4 | Issue:14|Papers Count:12

Introduction: The aim of this study was to investigate the morphological and ultrastructural changes of mouse endometrium by daily injection of progesterone, after ovarian hyperstimulation during preimplantation period. Material and Methods: NMRI mice, 6-10 weeks old, were initially hyperstimulated using hMG and hCG injection and then daily progesterone injection was performed subcutaneously (1 mg/mouse), thereafter they were mated artificially. 3.5 days after hyperstimulation, the animals were killed by cervical dislocation and the samples were obtained from 13 middle part of uterine horns. Specimens were also obtained from naturally and artifically impregnated control groups. The samples were divided and processed for light (H&E , PAS) and electron microscopic studies.Results: Our results indicated that, daily injection of progesterone after hyperstimulation decreased the height of the epithelium. In the experimental group several fat droplets were seen in the basal part of epithelium. Also intercellular spaces were decreased decidualization was not seen.Conclusion: Results show that daily injection of progesterone after hyperstimulation altered the ultrastructure of endometrial epithelium which resulted in inhibition of decidualization reaction and can affect the uterine receptivity during implantation.

Introduction: The aim of this study was to demonstrate changes in nature of mucin and production of acidic forms using PAS-Alcian blue stain at PH=2.5. Appearance of non-goblet metaplastic columnar cells of lower esophagus is considered as an early sign of Barrette sophagus, simultaneous in conjunction or before the appearance of goblet cells in patients with gastroesophageal reflux disease.Material and Methods: Forty four biopsy samples where taken from the squamo-columnar junction of patients with reflux associated columnar metaplasia of lower esophagus who referred to Shariati Hospital during 1378. All specimens were stained by Alcian blue-PAS at PH=2.5 to search for acidic mucin production in non-goblet metaplastic columnar cells of lower esophagus. Colonic mucosa specimen and the goblet cells from 9 cases with overt intestinal metaplasia were used as external and internal positive controls and cardiac type columnar cells were considered as negative control for acidic mucin production.Result: Eight out of 44 biopsy samples taken at squamo-columnar junction of patients with reflux associated columnar metaplasia in lower esophagus showed acidic mucin production in non-goblet metaplastic columnar cells. Conclusion: Alcian blue-PAS stain at PH=2.5 can demonstrate changes in nature of mucin content and reveals acidic mucin production in non-goblet metaplastic columnar cells of lower esophagus in some patients with gastroesophagea appearance of goblet cells and can help in early detection of this premalignant lesion and as a result, better surveillance and follow up of the affected patients.

Introduction: The role of adenosine A1 receptors of the entorhinal cortex on amygdaloid kindled seizures was investigated.Material and Methods: Animals were kindled by daily electrical stimulation of amygdala. In the full kindled animals, N6-cyclohexyladenosine (CHA; 0.1, 1 and 10 mM), an adenosine A1 receptor agonist, and 8-cyclopenthyle 1,3-dimethylexanthine (CPT), an adenosine A1 receptor antagonist, at concentrations of 1 and 5mM were injected bilaterally into the entorhinal cortex. Animals were stimulated at 5, 15, 60 and 120 min post drug infusion and kindling parameters were measured. Results: Results showed that CHA at concentration of 10 mM reduced amygdala after-discharge duration, entrorhinal cortex after-discharge duration (E-ADD) and stage 5 seizure duration at 5, 15,60 and 120 min post drug injection. It also increased the latency of stage 4 seizure. But, no alteration was observed in seizure stage. At concentrations of 1 and 0.1 mM, CHA reduced E-ADD only at 5 and 15min post drug infusion. Bilateral injection of CPT into the entorhinalcortex did not alter seizure parameters. Intra-entorhinal cortex injection of CPT (5mM), 5 min before CHA (10mM), blocked the anticonvulsant effects of CHA. Conclusion: These results suggest that the entorhinal cortex has a role in seizure propagation from the amygdala and its adenosine A1 receptors activity have anticonvulsant effects on amygdala kindled seizures.

Introduction: The learning procedure leads to biochemical, biophysical and ultrastructural changes in synapses of some specific areas in central nervous system, which is named synaptic plasticity.Material and Methods: Twelve male wistar rats were divided in two (case and control) groups. The cases were trained in Morris water maze. The animals underwent 8 training sessions per day, on 3 consecutive days, but the control group did not undergo this training. In the third day all rats were perfused with normal saline and Karnowsky fixator, under deep anesthesia. Then they were decapitated and their brains were enucleated. The CA1 area of dorsal hippocampal formation was punched about - 3.5 to - 4.5mm from Bregma, and the punched pieces were processed for TEM.Results: In comparison with the control group, the case group showed increase in concave synapses, decrease in thickness of postsynaptic density (PSD), vasting of synaptic contact zone (SCZ), formation of perforated postsynaptic density and V- shaped synapses. Conclusion: The results of this study showed that spatial learning leads to a series of ultrastructural changes in synapses of CA1 area of dorsal hippocampal formation which results in enhancement of synaptic efficacy.

Introduction: Systemic application of capsaicin to neonatel rodents depletes their primary afferent C-fibers and also results in a wide variety of changes observable in adulthood. The manual methods used for stimulation of vibrissa provide limited information on response properties of barrel cortical Neurons. In this study the effect of C-fiber depletion induced by neonatal capsaicin (Cap) treatment on response properties of barrel cortical neurons, after controlled mechanical displacement, was examined in adult rats. Material and Methods: We destroyed C-fibers of neonatal rats by adminstration of capsaicin (50mg/kg dissolved in 10% ethanol, 10% tween 80, 80% salin, ip) in the first day of birth. Single unit recording was done on barrel cortical cell from both (untreated control and vehicle-treated) and Cap-treated adult rats. The magnitude and latency period of response to the controlled mechanical displacement of principal and peripheral vibrissa were recorded and analyzed.Results: The magnitude of responses evoked by deflection of principal and peripheral vibrissa in Cap-treated rats were significantly (P<0.001) higher than in control rats. There was no difference between control and Cap-treated rats in the response latency to principal vibrissae deflection. (P<0.467) But response latency was significantly decreased redused during peripheral vibrissa deflection (P<0.001). The magnitude of response during principal vibrissae deflection was higher and the response latency was shorter compared to peripheral vibrissae deflection in both groups.Conclusion: These results suggest that C- fibers play an important role in the natural functions of the somatosensory system and are probably required for normal shaping of the functional properties of central somatosensory neurons.

Introduction: In this study the effects of long-term potentiation (LTP) on short-term plasticity (STP) were examined. Material and Methods: Experiments were carried out on hippocampus of freely moving rats. The changes in the field potentials, which were evoked by delivering train of pulses at 25 Hz frequency, were examined before and after induction of LTP.Results: Stp was different in potentiated synapses. LTP could potentiate only the first response. Conclusion: The interaction of LTP with STP would be important in information processing.

Introduction: Respiratory pathogen, chlamydia pneumoniae, has been implicated in the pathogenesis of coronary artery disease. Previous studies have demonstrated an antichlamydial seroresponse to be a cardiovascular risk factor and coronary atheromata to contain chlamyial components in varing proportions. Endovascular demonstration of bacterial DNA is required to provide evidence for an infectious component in atherosclerosis. Material and Methods: Atherectomy specimens from 102 patients who under- went surgery were examined for the presence of chlamydia pneumoniae by polymerase chain reaction (PCR). Each specimen was devided into multiple sections of 0.3 Cm2, and frozen at -20²C. Specimens were treated with glacial acetic acid and with a solution containing 0.32 Ml sucrose, 10 mM Tris - Hcl, 5 mM MgCl2 and triton x-100 (1% Vol/Vol) and incubated at room tempreture over night. There after DNA was extracted by first boiling for 20 minutes in NaOH and then by use of Tris buffer. DNA was percipitate with sodium acetate -ethanol by standard method.Results: C. Pneumoniae DNA was detected by PCR in atherosclerotic plaques of 23 patients (22%).Conclusion: Results of this study demonstrate a moderate prevalence of C. Pneumoniae DNA in atherosclerosis plaques. This study provides data on the possibility of C. Pneumoniae involvment in the pathogenesis of atheroclerosis and additional evidence for an association between this agent and atherosclerosis.

Introduction: Meningitis is one of the lethal diseases and its prompt diagnosis is of utmost importance. Current diagnostic methods (eg. bacterial cultures, cellular cultures, biochemical methods and cell count in CSF) are not sensitive enough. Therefore dorelopnga new method for quick diagnosis is essential.Material and Methods: We extracted DNA from cerebrospinal fluid and PCR was performed by primers which amplified the 16s rRNA sequence. Microbial culture was also performed for comparison.Results: We examined 51 specimens, among which 23.5% were culture positive. By PCR method, we reported 41.1 positive cases. Therefore if PCR is not used, almost half of the positive cases will be missed.Conclusion: We concluded that PCR is the best method of diagnosis, with high accuracy and precision for detecting microorganisms in sterile specimens in 3-4 hours. Since the 16s rRNA sequence has been similar in all prokaryotes, this sequence is considered appropriate for target for PCR.