Journal of Isfahan Medical School
Year:2013 | Volume:31 | Issue:228|Papers Count:6

Background: In the critical period of brain development, in addition to natural function of neurons, the environmental signals strikingly affect the brain structure and function. In this study, the developmental effect of dark rearing on induction of long-term potentiation (LTP) in responses of neurons of CA1 area of hippocampus was evaluated.Methods: This experimental study was carried out on 2 groups of male rats kept in a standard 12-hour light/dark condition (Light reared or LR) or a in complete darkness (Dark reared or DR) since birth through the study. Each group, in turn, was divided into 3 groups of 2, 6 and 10 weeks old subgroups (n=8 for each). Stimulating the perforant path, field potentials were recorded in the CA1 area for 30 minutes. Then, the tetanic stimulation was applied to the Schaffer collaterals and the field potentials were pooled for 120 minutes post-tetanus.Findings: While the response amplitude of the basic responses demonstrated an age-dependent decrease in the LR animals, it showed a substantial increase in the DR ones. Dark rearing declined the degree of potentiation in the tetanized responses; however, the post-tetanus recordings showed a significant LTP yet. The LTP induction was reduced in either LR or DR animals.Conclusion: It seems that the visual experience modifications weaken both basic responses and LTP induction in neurons of CA1 area of hippocampus.

Background: Atherosclerosis is a chronic inflammatory disease. There are several inflammatory molecules involved in the development of atherosclerosis. Among them, C - reactive protein (CRP) is the best known biomarker for disease progression, plaque instability and fragility. This study aimed to determine the correlation of the venous CRP with plaque CRP in patients undergoing elective coronary artery bypass graft (CABG) surgery.Methods: This study was done on 22 men with diabetes mellitus candidate for CABG surgery. Blood samples were taken from patients before surgery to determine the venous blood CRP level. The atherosclerotic plaque was removed from the vessel wall during the surgery. Samples of coronary atherosclerotic plaques were stained with Hematoxilin and Eosin to measure intima and media thickness and calculate the intima to media ratio (IMR). The immunohistochemistry staining was used to determine the CRP expression levels. Venous blood hsCRP concentrations were determined by ELISA method.Findings: There was no significant correlation between the intensity of CRP expression in atherosclerosis plaques and hsCRP concentrations in venous blood; but there was a significant correlation between the venous blood hsCRP concentration and severity of atherosclerosis (the IMR).Conclusion: Increased CRP represents systemic inflammation in the body and is correlated with the severity of atherosclerosis; so, it can be a reliable biomarker of disease progression. Despite of the existence of CRP in the atherosclerotic plaque, there is no correlation between the expression of CRP and hsCRP concentrations.

Background: Anaphase promoting complex (APC) plays a critical role in cell division and mitotic exit. This protein complex may have a pivotal role in the cell cycle control affecting pathological conditions such as cancer. APC is recommended as the target of many anti-cancer agents due to its importance in cancer pathogenesis. This study aimed to evaluate the inhibitory effects of curcumin and 2-methoxyestradiaul on APC.Methods: Hela cells were treated with various concentrations of curcumin and 2-methoxyestradiaul, and their cytotoxic effects were investigated after 24, 48, 72 and 96 hours by MTT assay. Expression of securin, cyclin B and the APC substrates were investigated using immune-blotting. Finally, cell cycle analysis was performed using DRAQ5 staining and flow cytometry.Findings: Respectively, 20 and 30 percent of cell-death after 24-hour treatment with curcumin and 2- methoxyestradiaul was seen. Also, securin and cyclin levels were raised after 24 hours of treatment. Furthermore, the levels of the substrates (securin and cyclin B) increased 48 hours after treatment. Results of fluorescence-activated cell sorting (FACS) analysis showed that treated cells were arrested in G2 phase of cell cycle which revealed cell arrest in G2 phase of cell cycle. 2-methoxyestradiaul showed a better APC inhibition effect than curcumin (P=0.02).Conclusion: Our results revealed that APC is a suitable target for cancer treatment and curcumin and 2-methoxyestradiaul have inhibitory effects on the activity of this complex.

Background: In Iran, general anaesthesia is more common than other anaesthetic methods in caesarean section and it is the first choice for pregnant mothers. So, we designed this study to compare the effect of isoflurane and propofol on mother’s awareness and APGAR score in the neonatal delivered by selective caesarean section.Methods: In this double blind clinical trial study, 90 pregnant women (18-35-years old) with American Society of Anesthesiology (ASA) classification 1 or 2, who were condidate for selective caesarean, randomly assigned to two groups. Induction of anaesthesia was provided by propofol and succinylcholine in the same way, and maintenance of anaesthesia was provided by propofol in group 1 (100 mg/kg/min) and with isoflurane 1 MAC (Minimum alveolar concentration) in group 2 to maintain Bispectral index score (BIS) between 45 and 60. For statistical analysis t and chi-square tests were used.Findings: There was not a significant difference between the two groups in basic information, neonatal APGAR scores, and hemodynamic changes. 7 of 90 patients had dreams after being awakened (8.9 vs 6.7 percent in propofol and isoflurane groups, respectively) but no significant difference was detected.Conclusion: There was not a significant difference between two groups in Oncidence of awareness, neonatal APGAR scores, and hemodynamic changes which correlated with other studies. Although, more studies with larger sample size needed to compare the effect of these two drugs.

Background: P-glycoprotein 170 is encoded by MDR1 gene and belongs to the ATP-binding cassette transporters (ABC) superfamily. This protein has important roles in cell physiology and its function in cancerous cells may contribute to failure treatment. The molecular structure of P-glycoprotein and its corresponding gene is introduced in this research. Moreover, the pathophysiological role of this protein and its effects on pharmacokinetics are discussed.Methods: EBSCO, Elsevier, PubMed and OVID databases were reviewed to introduce the most recent studies regarding p-glycoprotein, MDR1 and their clinical importance in health and disease. Authors’ novel findings regarding MDR1 and leukemia were also discussed.Findings: P-glycoprotein is naturally expressed in many tissues such as liver, intestine and brain. This protein is involved in many cellular processes such as inflammation, immune cell differentiation, detoxification and hormone secretion. Reduction of the treatment efficiency and the consecutive relapse due to drug resistance are the most important consequences of this protein function, and addressed as the most challenging obstacles in cancer treatment.Conclusion: P-glycoprotein is an important transporter with a protecting function in normal cell life. On the other hand, it may provide drug resistance in some cancerous cells. Comprehensive studies about MDR1 and P-glycoprotein 170 may provide novel approaches to new diagnostics and therapeutics.