Showing 7 results for Parivar
Volume 11, Issue 0 (بهار و تابستان 87- 2008)
Abstract
Objective: Helicobacter pylori is a spiral, microaerophilic gram negative bacterium, that multiplies and causes infection in human gastric mucosal layer. H.pylori infection, followed by destruction of gastric epithelial tissue, leads to gastric chronic inflammation, which can cause gastric and peptic ulcers. New approaches have focused on using specific treatments, such as immunotherapy, to eradicate this infection. Urease, as one of the most important virulent and antigenic factors of the bacterium, is a suitable target for this purpose. This study is aimed at production of specific IgY against urease UreC subunit.
Materials and Methods: In this study, initially for preparing recombinant UreC, after purification of the genomic DNA, ureC gene was amplified by polymerase chain reaction (PCR). The PCR product was ligated to pET28a. The recombinant protein was expressed followed by transformation of recombinant construct into E. coli BL21DE3. SDS-PAGE analysis was carried out and the recombinant protein was purified by Ni-NTA affinity chromatography. The purified recombinant protein was injected to hens. IgY recovered from egg yolk, was purified by PEG precipitation at >70% purity. The purified IgY was analyzed by ELISA and SDS-PAGE.
Results: SDS-PAGE analysis revealed a good expression and >70% purification of the recombinant protein. ELISA observation demonstrated high immunogenicity of the recombinant protein.
Conclusion: With a view to higher potential of IgY-HpUc in recognition of UreC subunit, the results are in favour of the oral administration of the IgY obtained from hens immunized by H.pylori may provide a novel approach to the management of H.pylori infections.
Volume 12, Issue 4 (10-2010)
Abstract
Objective: The LRR (leucine rich proteoglycans) is a molecular recognition motif found in proteins with some roles in cell adhesion, signal transduction, DNA repair and RNA processing. Opticin is a member of this family. Takanosu et al (2001) detected messenger RNA expression of mouse opticin in the eye, heart, brain, testis, thyroid and epididymis by dot blot hybridization.
In this study, expression levels of mRNA and protein of opticin was investigated by two monoclonal antibodies which were raised against opticin peptides. By this method structure of opticin in human and mouse has been studied.
Materials and Methods: Mouse tissues including, kidney, testis, liver, lung, heart, brain, muscle, spleen and eye were isolated. Opticin expression was identified at mRNA and protein levels by RT-PCR and Western blot.
Results: PCR analysis revealed that opticin mRNA is expressed in all the tissues studied except for the lung. However, opticin protein was detected in all tissues analyzed.
Conclusion: Expression of opticin in the adult murine tissues may suggest functions other than that of putative regulation of vitreous collagen fibrillogenesis for this molecule.
Volume 15, Issue 3 (10-2012)
Abstract
Objective: The goals of the study are evaluation the effect(s) of food deprivation as a social stress on testis structure. We also investigated the effects of melatonin treatment as an antioxidant component and inequality on the effect(s) of food deprivation. Methods: We investigated the improving effects of melatonin and social stress (food deprivation) on 42 male rats in 7 groups including control, sham, melatonin received (M), food deprivation (1/3 of control daily food) plus observation (FD), FD + melatonin (FDM), isolated FD (FDi), and FDi + melatonin (FDMi) groups. After 14 days, rats' testes were studied using immuno histochemistry and TUNEL assays to determine the number of apoptotic cells. Biochemical evaluation was taken on malodialdehide (MDA) and glutathione (GSH). ANOVA and Tukey's tests were done to analyse the data. PResults: The results of sham group was declined for similarity to results of control group. In FD group, MDA was increased significantly (PConclusion: Food deprivation can induce oxidative stress which is associated with increasment of apoptotic cells in testis. Isolation can compensate these effects. These results refer to inequality. Since melatonin is recognized for its anti-oxidative and improving effects, we have shown involvement of oxidative stress mechanisms on the stress of food deprivation with inequality.
Arman Hamidi, Seyed Mostafa Mirsalim, Barat Ghobadian, Amirhossein Parivar, Saeed Abdolmaleki,
Volume 15, Issue 5 (7-2015)
Abstract
Biodiesel is a renewable and sustainable alternative fuel that is derived from vegetable oils and animal fats. In this paper an experimental investigation is conducted to evaluate the use of soybean oil methyl ester (biodiesel) in the diesel fuel at blend ratios of B0, B2, B5 and B10. In this study, the performance and emissions characteristics of conventional diesel fuel and biodiesel fuel blends were compared. The tests were performed at steady-state conditions in a direct injection diesel engine with 90 kW power that was equipped with EGR and with no modification of calibration. The experimental results of brake-specific fuel consumption (BSFC), torque and exhaust temperature as well as carbon dioxide (CO2), smoke, nitrogen oxide (NOx), carbon monoxide (CO) and unburned hydrocarbon (UHC) emissions were presented and discussed. The results of engine performance parameters at different conditions (different load and engine speed) showed that a negligible loss of engine power and a significant increase in brake specific fuel consumption due to lower heating value of biodiesel. Smoke, CO and HC emissions were decreased by increasing blends of soybean oil as compared to pure diesel. However the increase in engine NOx and CO2 emissions were observed with the increase of biodiesel percentage in the blended fuel.
Sepideh Sarmast, Amirhossein Shamekhi, Masoud Zia Basharhagh, Amirhossein Parivar,
Volume 17, Issue 1 (3-2017)
Abstract
Fuel consumption, emissions and output power are some of the very important factors for automotive engine design. Since the combustion efficiency depends on the quality of the air-fuel mixture and mixture quality depends on the fuel injection parameters, the investigation of spray features is an overall goal in direct injection engines. In this paper, simulation of GDI spray is carried out in a constant volume chamber contains nitrogen in four different injection pressure using the AVL Fire software. The results are validated against the Istituto Motori-CNR experimental data. The log-normal probability distribution as an initial droplet diameter and Huh-Gosman model as secondary breakup were used. Then the combustion of EF7 Engine with direct injection was studied and wall film thickness was compared at different injection pressures and injector angles. Also, the effects of wall temperature and single-stage and two-stage fuel injection with different ratios of injected fuel mass were evaluated on the wall film. Since the fuel can be injected into the combustion chamber in both intake and compression stroke according to engine operating conditions in gasoline direct injection engines, the simulation was done for open cycle engine.
Sepideh Sarmast Sakhvidi, Amir Hossein Shamekhi, Masoud Zia Basharhagh, Amir Hossein Parivar,
Volume 17, Issue 3 (5-2017)
Abstract
The main aim of this paper is the numerical investigation of air-fuel mixture formation and spray and combustion characteristics of EF7 engine equipped with spray-guided direct injection system. For this purpose, first, a six-hole injector is simulated in three different injection pressures and to validate the fuel injection characteristics, the results are validated against the Istituto Motori-CNR experimental data. Then, the injector position is selected near the spark plug and by changing of injector angle relative to the axis of combustion chamber, the appropriate angle for optimization mixture formation is obtained. Then, the effect of injection pressure, start of first and second injection as well as the effect of two-stage fuel injection with different proportions of fuel mass at primary and secondary injection are studied on the mixture formation, wall film and engine emissions. The results showed that the injector angle is extremely effective on the mixture formation, pressure and the amount of unburned hydrocarbons due to its direct impact on wall film mass. Also, in the two-stage injection, relatively homogeneous lean mixture compared to the stratified mixture results better combustion at part load condition.
Volume 22, Issue 4 (Fall 2019)
Abstract
Aims: The aim of the present study was to evaluate the effects of lysophosphatidic acid (LPA) supplementation of human ovarian tissue culture media on the morphology of tissue and alteration in angiogenesis by expression of vascular endothelial growth factor (VEGF) after transplantation.
Materials & Methods: In the present experimental study, the human ovarian tissues (n=8) after collection from female-to-male transsexual people, were cut into small fragments (n=98). Then, vitrified-warmed and cultured 24 hours in two groups in the presence and absence of LPA, and finally they were transplanted to γ-irradiated mice (n=13). After two weeks the morphology of tissues was studied by hematoxylin and eosin staining and VEGF protein was detected by immunohistochemistry. The expression of VEGF gene was evaluated by real time RT-PCR.
Results: The morphology of both transplanted tissues was well preserved and follicles at different developmental stages were seen in all studied groups. Significantly a higher expression of VEGF gene was observed in the LPA-treated group compared to the non-treated once (p<0.05). Several blood vessels were shown positive reactions for VEGF antibody as green color in stroma of ovarian tissue sections in all studied groups.
Conclusion: Supplementation of human ovarian tissue culture media with LPA before transplantation could increase the expression of VEGF gene related to angiogenesis.