Tehran University Medical Journal

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Background: Job stressors in managers are progressively affecting and destroying their immune systems. The relationship between hardiness, stress and immune system is important for mental health. This study was designed to determine the resources in managers against stress, resources herein designated as “hardiness” and “social support". Also in this research, the correlation between hardiness, defined collectively as feelings of challenge, commitment and control, as a resource against stress and the immune system of high school managers in Khozestan Province were studied.
Methods: The study sample was comprised of 340 managers (male and female), selected by the cluster sampling method. Each subject completed the personal view survey scale and social support questionnaire. Then the individuals were divided into four groups (n= 35 in each group) of high and low hardiness and social support as follows: high hardiness / high social support, high hardiness / low social support, low hardiness / high social support and low hardiness / low social support. Subjects who suffered from disorders that affect the immune system were excluded. The number of T-helper cells (CD4), T-suppressor cytotoxic cells (CD8), natural killer cells (CD56+ CD16), complement system (C3, C4, CH50), immunoglobulin M and G (IgM and IgG), cortisol hormone, eosinophils, neutrophils and lymphocytes were measured for each subject.
Results: The results revealed that, there was a significant positive correlation between hardiness and CD4, CD4/CD8, CD56, CD16, CH50, IgM and neutrophil levels. Also, there was a significant negative correlation between hardiness and CD8, cortisol and eosinophil levels. There was a significant difference between the four groups of in CD4, CD8, CD4/CD8, cortisol, C3, C4, CH50 and lymphocyte levels. Also, there was a significant positive correlation between social support and CD4, CD4/CD8, CD56, CD16, CH50, IgM, C3 and neutrophil levels.
Conclusions: The results revealed that the performance of the immune system in managers with high hardiness and high social support is significantly better than that of managers with low hardiness and low social support. Furthermore, high hardiness and high social support act as resources and moderating factors against stress.

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Background: There is a growing interest in understanding the biological effects of time-tested folk medicinal plants including the green leafy vegetables, which supply minerals and vitamins to the diet. Trigonella foenum-graecum L (fenugreek) is a dietary vegetable and there are reports concerning its antinociceptive effects in Iranian traditional medicine. Its seeds are also known for their carminative, tonic, antidiabetic, antineoplastic and restorative properties. These reports and the hypoglycemic effect of fenugreek leaf extract encouraged us to assay fenugreek aqueous extract for cytotoxicity on NIH3T3 mouse fibroblast cells.

Methods: The NIH3T3cell line was purchased from National Research Center for Genetic Engineering and Biotechnology of Iran. The cells were plated in 24-well microtiter plates with DMEM+F12 medium containing 10% fetal calf serum supplemented with 445 mg/L L-glutamine and maintained at 37^oC with 5% CO₂/95% air. Following a 24-hr incubation period, various concentrations (0.01-20 mg) of the extract to the culture wells. Cell viability was assessed using trypan blue and MTT assays after five days of incubation.

Results: The results show that the IC₅₀ of the fenugreek extract as calculated from the trypan blue and MTT assays were 1.25 and 2.5 mg/mL, respectively.

Conclusions: Our findings, therefore, suggest that the aqueous extract of fenugreek is classified as nontoxic. This observed cytotoxicity is not specific and could be due to membrane disturbances.

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Background: Human cancer cell lines express human choriogonadotropin (hCG), its subunits and derivatives, regardless of their origin and type. It appears that hCG is a common phenotype in human cancer cell lines. In this research, the effects of hCG targeting monoclonal antibodies (7D9, T18H7 and T8B12) on human cancer cell lines were evaluated.
Methods:  Monoclonal antibody secreting hybridomas were proliferated and injected intraperitoneally to Balb/C mice after treatment with pristine. Two weeks later, ascites fluid was collected. Purification of aforementioned antibodies from ascites fluid was performed using G-protein affinity followed by ion exchange chromatography. SDS-PAGE and ELISA confirmed the structure and functional integrity of the purified antibodies, respectively. Two human cancer cell lines "Hela" and "MDA" were treated by the purified antibodies. Three days later, different wells were imaged and the cells counted.
Results:  SDS-PAGE gel (None-reducing) indicated consistency of band migration patterns with control antibodies. ELISA test using hCG antigens indicated that the produced antibodies could detect hCG antigens. Cell lines were cultured and treated with different concentrations of each antibody. Counting and imaging different wells of treated plates, indicated that 7D9 antibody had a more significant (P<0.01) cytotoxic effect on cancer cell lines than the control cells.
Conclusion: HCG targeting monoclonal antibodies can be used for targeted cancer therapy, as human cancer cells express hCG gene. 7D9 antibody that exhibits protease activity is a proper candidate for this purpose, as it possesses both antagonistic and enzymatic properties.

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Background: Regarding the immunomodulatory effects of lactobacillus bacteria, this study aimed to evaluate the effect of oral administration of Lactobacillus reuteri, as probiotic bacteria, on natural killer cell cytotoxicity and tumor-specific lymphocyte proliferation in Balb/c mice with breast adenocarcinoma.

Methods: A total of 30 female mice, aged 6- 8 weeks and with a weight of approximately 17- 19 g, were randomly divided into two groups of 15 mice. The case group received Lactobacillus reuteri at a dose of 2.7× 108 bacteria in half a milliliter of sterile phosphate buffer saline (PBS) and the control group only received PBS. The probiotic group received the regimen for two weeks prior to tumor transplantation, as they did for 30 days after transplantation with three-day intervals and durations of seven days. For the evaluation of natural killer cell cytotoxicity and also tumor-specific lymphocyte proliferation response, LDH and BrdU assays were performed respectively according to the manufacturers' instructions.

Results: The study showed that the mice in the case group which were receiving Lactobacillus reuteri had statistically significant differences in the replication of tumor -specific lymphocytes, natural killer cell cytotoxicity and delayed hypersensitivity responses Compared to the mice in the control group.

Conclusion: Daily consumption of probiotics seems to regulate the immune system and consequently it can be helpful in people with cancer. Moreover, consumption of probiotics in healthy individuals can also boost the efficiency of the immune system against a variety of abnormalities.

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Background: Biosynthesis of nanoparticles has attracted the attention of the scientific community in nanotechnology and biotechnology due to their extensive application in the area of material sciences and medicine. Nowadays, despite a various application of nanomaterial’s, there is a little information about their impact on human health. In this study, we investigated the comparative study on cytotoxicity effect of biological and commercial synthesized nanosilver on human gastric carcinoma (AGS) and normal lung fibroblast (MRC-5) cell lines. Methods: The current experimental study was carried out in Islamic Azad University, East Tehran Branch, from April to November 2014. The biological synthesis of nanosilver was obtained from Eucalyptus plant extract as a reducing agent. Further to more analysis, morphological study on size and shape of developed biological nanosilver was characterized by performing scanning electron microscopy and dynamic light scattering. AGS and MCR-5 cell lines were treated with various concentration of nanosilver for 24, 48 and 72 hours. Finally, the cell viability was evaluated by using MTT assay. Results: The results show that the nanosilver exerts a dose-dependent inhibitory effect on viability of cells. At 100µg/mL of commercial and biological synthesized nanosilver, the viability of AGS was reduced to 7.47±0.002% (P=0.002) and 3.65±0.01% (P=0.003) after 72 hours, respectively. In addition, the viability of MRC-5 at the same condition was reduced to 10.27±0.19% (P=0.001) and 9.16±1.53% (P=0.002), respectively. Conclusion: Based on a thorough literature surveys, the present study is the first research about biosynthesis of nanosilver using Eucalyptus plant extract. This eco-friendly and cost effective method can be used for large scale production of silver nanoparticle. In addition, based on the current obtained data, commercial and biological synthesized nanosilver can more inhibitory effect on cancer cells compared to the normal cells. Hence, silver nanoparticles might be used as a new strategy for treating many human cancers. However, further studies are necessary to ascertain their potential as anticancer agents.

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Background: Aloysia citrodora belongs to the Verbenaceae family of plants, a well-known herbal medicine in Iran. The aim of the present study was to investigate the chemical composition, antioxidant, antibacterial, cytotoxic and apoptotic effect of A. citrodora extract against human colon cancer (HT29) cells by using real-time polymerase chain reaction and flow-cytometry methods.

Methods: This experimental study was carried out in Islamic Azad University, East Tehran Branch, from March to September of 2014. At first, the A. citrodora chemical constituents were analyzed by gas chromatography-mass spectrometry (GC-MS) technique. In addition, antioxidant assay, antibacterial and anti-cancer effect was performed using 1,1-diphenyl-2-picrylhydrazyl (DPPH), disk diffusion and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) methods, respectively. The half maximal inhibitory concentration (IC50) value was calculated. We extracted total RNA molecules by using RNX solution, after which cDNA was synthesized. Finally, the pro-apoptotic (Bax) and anti-apoptotic (Bcl2) gene expression was performed by real-time polymerase chain reaction and apoptotic effects were analyzed using Flow-cytometry method.

Results: GC-MS analysis of Aloysia citrodora extract was shown 37 major components and the most frequent component was belonged to Spathulenol (17.57%) and Caryophyllene oxide (15.15%) The antioxidant activity of the extract was IC50= 0.6±0.03 mg/ml. The maximum and minimum antibacterial effects of extract were belonged to gram-negative and gram-positive bacteria, respectively. Cytotoxic results revealed that the A.citrodora extract have IC50= 20.1±0.78 mg/ml against colon cancer (HT29) cell line and real-time polymerase chain reaction results showed the expression level of Bax and Bcl2 was increased and decreased respectively in colon cancer cell line (3.470±0.72 (P< 0.05), 0.43±0.35 (P< 0.05)). In addition, the flow-cytometry results indicated the 38.66% apoptosis in colon cancer cell line.

Conclusion: According to the results, it seems that A. citrodora extract has potential antioxidant, antibacterial and anticancer effects and it suggested that further studies were performed for A. citrodora pharmaceutical importance.

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Background: Hydroxyapatite nanoparticles have a more surface contact and solubility than conventional hydroxyapatite. Hydroxynanoparticles enhances the biological and mechanical properties of new regenerated tissues. The hydroxyapatite nanoparticles have received attention as a new and effective osseous graft for using as scaffolds in bone regeneration. The reports on hydroxyapatite nanoparticles biocompatibility are controversial. It has been shown that hydroxyapatite nanoparticles induces inflammatory reaction and apoptosis. The aim of the present study was to evaluate the cytotoxicity of nano-hydroxyapatite on the human epithelial cells.

Methods: The study was experimental and completed in vitro. The study was carried out in department of Immonulogy, Faculty of Medicine, Shahid Beheshti University of Medical Sciences in November 2014. The human-derived oral epithelium cell line (KB) obtained from Pasteur Institute, Tehran, Iran were exposed to hydroxyapatite nanoparticles at 0.01, 0.05, 0.1, 0.5, 0.75, 1, 2.5 and 5 mg/ml concentrations in 24, 48 and 72 hours. Rod-shaped hydroxyapatite nanoparticles with 99% purity and maximum 100 nm sized particles were used. Methylthiazol tetrazolium bromide (MTT) method was employed for cell vitality evaluation. Enzyme-linked immunosorbent assay (ELISA) was used for assessing the viability of cells. Distilled water and fetal bovine serum (FBS) were positive and negative controls. ANOVA and Duncan tests were used for statistical analysis.

Results: The cytotoxicity of different concentrations of hydroxyapatite nanoparticles on human-derived oral epithelium cell line in 24 (P< 0.001), 48 (P< 0.001) and 72 hours (P< 0.001) was significantly different. The nano-hydroxyapatite particles at 0.5 to 1 mg/ml had the highest cytotoxicity effect on human-derived oral epithelium cells in 24, 48 and 72 hours. Lower concentrations than 0.05 mg/ml had the best biocompatibility properties in 24, 48 and 72 hours.

Conclusion: Hydroxyapatite nanoparticles had a good biocompatibility. The biocompatibility of hydroxyapatite nanoparticles were dose and time dependent. The lower concentrations than 0.05 mg/ml of nano-hydroxyapatite had the best biocompatibility over time.

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Results: The phytochemical analyses of T. cherleri extract showed the 20 major components and the most frequent component was belonged to hexadecanoic acid, ethyl ester (20.7%) and 2-Pentadecanone, 6,10,14-trimethyl (19.9%). The extract had maximum antibacterial effects against Staphylococcus aureus and Streptococcus pyogenes. There was a dose dependent increase in the cytotoxicity effect of extract against A549 cancer cell. Moreover, the Real-Time PCR results indicated that the caspase 3 and caspase 9 gene expression was significantly up-regulated 2.57±0.27 (P<0.05), and 3.3±0.46 (P<0.05), respectively.

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Methods: In the present study, which was conducted experimentally from May to September 2018 in bacteriology and Cellular and Developmental Research Centers of Islamic Azad University, Shahrekord branch, the antimicrobial activity of supernatant of Lactobacillus sakei was assessed by Well Diffusion Agar (WDA) method against some pathogenic bacteria. HT-29 Colorectal adenocarcinoma cancer cells were cultured in DMEM medium with 10% bovine serum. The cells were treated in 5, 15, 10 and 20 mg/ml concentrations of sakei metabolites and incubated at 24, 48 and 72 hours. Cell growth was analyzed by celltiter 96® aqueous one solution cell proliferation assay kit to the manufacturer's protocol in all three incubation times. Results: The results of this study indicate that sakei was able to produce antimicrobial metabolites against pathogenic bacteria. Besides, the results of the celltiter 96® aqueous one solution cell proliferation assay showed that the bioavailability of HT-29 cell lines decreased at all concentrations of sakei metabolites in a dose and time-dependent manner. Conclusion: Since lactic acid probiotic bacteria can alter the metabolic activities of the intestinal microflora, attach to carcinogens and destroy them, prevent carcinogenesis such as ammonia and secondary bile acids, producing anti-cancer substances and creating an acidic state to inhibit the growth and proliferation of carcinogenic bacteria, It seems that there is a good research field for the use of bioactive compounds produced by Lactobacillus sakei in the control of bacterial pathogens and treatment of human colorectal adenocarcinoma (HT-29).