فهرست مطالب مرتضی دلیری

The most common method for peptide synthesis is to synthetize it on a solid resin. Among the variety of resins, Wang resin is one of the highly use ones. In this study, we introduced improved protocols for anchoring an amino acid on the Wang resin, a famous resin for peptide synthesis, and N-terminally labeling peptide with (5/6)-carboxyfluorescein, a fluorescent dye. The peptide tetra arginine, RRRR, was synthetized on Wang resin with solid phase peptide synthesis (SPPS) method and the dye was attached to its N-terminus. The attachment yield of the first arginine residue (Fmoc-Arg(pbf)-OH) were quantified by liberating the Fmoc groups from the amino acid/resin complex following measure its UV absorption at 278 nm. The labeling was monitored by Ninhydrin test that reveals presence of primary, unbound N-terminally amines. In anchoring the first arginine residue on the resin, DIC (N,N’-Diisopropyl carbodiimide) works more efficiently than HBTU (N,N,N′,N′-Tetramethyl-O-(1H-benzotriazol-1-yl)uronium hexafluorophosphate), only if the incubation time increases to 17 hours; while, HBTU undeniably enhances the efficiency of the fluorescence labeling compared to DIC. However, in most available protocols, DIC was recommended for labeling the peptides with (5/6)-carboxyfluorescein and the recommended incubation time for attaching the first amino acid on the Wang resin is usually far shorter than 17 hours.

Primary cell lines were established from the culture of explants of caudal fin of Persian sturgeon, Acipenser persicus. The margin of the caudal fin from a two year old specimen (23 cm in length, and 133 g in weight) was aseptically cut (2 cm), washed three times with PBS containing antibiotics and then minced into 1 mm explants and cultured in L-15 medium complemented with antibiotics and FBS (20% ) at 22 °C. After confluent monolayer formation on the bottom of the flask, the cells were washed with PBS containing antibiotics and dislodged by trypsin-EDTA solution (0.25%) and shaking the flask. After washing the cells with PBS containing the antibiotics, they were cultured in 5 ml of L-15 medium, FBS (20%), antibiotics at 22 °C (first subculture). After a confluent monolayer formation, a similar procedure was followed for the second subculture.The emerging cells from explants exhibited fibroblast-like and epithelial-like cells in primary culture but the fibroblast-like cells were seen to predominate after the first subculture. In the present study the establishment of cell lines from the original culture at two passages was investigated.

Although studies have shown that viability rate of transferred blastocysts in comparison to embryos in previous stages is higher, the viability rate of warmed blastocysts was lower than embryos in other stages. This can be attributed to the present of fluid filled blastocoel cavity and potential risk of ice crystal formation. Moreover, the fluid can serve as an isolator against penetration of cryoprotectant agents (CPAs) to the embryos. In the present study by applying artificial collapse (AC) on blastocysts, we aimed to evaluate the effect of reduced volume of blastocoele fluid prior to vitrification on the quality of warmed in vitro mice embryos. In this regards, quantity of Fgf4 gene expression, viability and hatching rates were considered. Mouse blastocysts divided into 3 groups including: A) Vitrified-thawed blastocysts after artificial collapse, B) Vitrified-thawed blastocysts, C) Fresh blastocysts as a control group. The survival and hatching rate of embryos were evaluated by SPSS and one way ANOVA with post hoc Duncan test and the expression of Fgf4 gene was assessed by Real Time PCR technique in comparison to control group. Artificial collapse improved the rate of zona pellucida hatching showed a significant increase (p<0.05). Moreover, the level of Fgf4 gene expression in the AC group increased significantly (p<0.05) in comparison to the control group. It can be concluded that artificial collapse of blastocyst could be effective way to improve the implantation rate.

Aim and Tissue engineering is a promising area in biomedical engineering to repair or replace the function of defective or damaged tissues or organs. Recently, tissue engineering has provided a new medical therapy as an alternative to conventional transplantation methods by using polymeric biomaterials with living cells. The scaffold provides the microenvironment (synthetic temporary extracellular matrix) for regenerative cells, supporting cell attachment, proliferation, differentiation, and neo tissue genesis due to their suitable chemical, physical and biological. In this research, chitosan/laminin nanocomposite was exploited as scaffold for suitable cell proliferation. Freeze-drying technique was used to fabricate chitosan/laminin-nanocomposites for L929 fibroblast cellsseeding, proliferation and attachment. The physico-chemical properties of the scaffold were fully characterized by using scanning electron microscopy (SEM). Consequently, the biocompatibility of scaffold was evaluated by biocompatibility test. The microstructure observation with SEM suggests the formation of cylinder-shaped porous structure and interconnected porosity. Our results demonstrated that the nano-sized chitosan/laminin scaffolds are nontoxic and biocompatible which can promote proliferation and attachment of L929 fibroblast cells. And their appropriate adhesion to nanocomposite for improved tissue engineering applications.

Assessing genetic biodiversity and population structure of minor populations through the information provided by neutral molecular markers, allows determination of their extinction risk and to design strategies for their management and conservation. Analysis of microsatellite loci is known to be highly informative in the reconstruction of the historical processes underlying the evolution and differentiation of animal populations. Iranian goat populations are recognized as an invaluable component of the world’s goat genetic resources. The aim of this work is to study the genetic status of Raeini goat population through the analysis of molecular data from 13 microsatellites markers. The mean expected heterozygosity across loci within populations ranged from 0.716 to 0.852. Genetic diversity measures revealed a good status of biodiversity in the Raeini goat population. The observed number of alleles ranged from 4 (ILSTS022) to 10 (BM121) with a total of 92 alleles and mean of 7.08 alleles across loci. The overall heterozygosity, PIC and Shannon index values were 0.808, 0.76 and 1.719 indicating high genetic diversity. Only 5 out of 13 loci were in Hardy-Weinberg equilibrium. The mean Fis was -0.016. Only 4 loci had positive Fis values and 9 loci had negative values. Genetic bottleneck hypotheses were also explored. Our data suggest that the Raeini goats have not experienced a genetic bottleneck in the recent past.

The aim of this study was to investigate the effece of mare serum and fetal bovine serum (FBS) on meiotic and fertilization capacity of sheep oocytes in vitro Cumulus Oocyte Complexes (COCs) were recovered from ovaries using slicing method. COC’s were washed three time in maturation medium without any serum supplementation. The COC’s were randomly divided into three groups. Group 1 (n = 170) COC’s were fresh control and cultured in maturation medium without serum supplementation. Group 2 (n = 169) COC’s were cultured in maturation medium supplemented with 10% mare serum. Group 3 (n = 167) COC’s were cultured in maturation medium supplemented with 10% FBS. Cumulus expansion was the index of oocyte maturation. To fertilize the mature oocytes، 24 h after maturation oocytes were transferred to the fertilization medium and then sperm was added to the fertilization medium. Twenty four hours post-fertilization، oocytes were denuded mechanically by gentle pipeting، fixed in a mixture of acetic acid and alcohol، stained for 10 min with 1% (w/v) orcein in 45% acetic acid and examined for their fertilization potential. The rate of oocyte maturation in groups 1، 2 and 3 were 59/82%، 77/55% and 89/27%، respectively. The rate of fertilization in three groups was 19/19%، 39/64% and 50%، respectively. Significant difference was observed between three groups (p < 0. 05). The results showed that the medium contain 10% percent fetal bovine have higher in vitro maturation and fertilization of oocyte rates than mare serum and the control groups

laser irradiation is a promising method for modifying and nano-structuring of the polymer surfaces. These nanostructures induced by laser irradiation can improve biocompatibility of polymers, significantly.

In this study, surface of polystyrene (PS) films were treated using ArF Excimer laser (wavelength=193 nm) at different number of pulses. The changes were characterized by atomic force microscopy (AFM), attenuated total reflectance Fourier transform infrared (ATR-FTIR), scanning electron microscopy (SEM) and contact angle measurements. L929 cell culture was used to investigate the biocompatibility of treated laser PS.

The data from ATR-FTIR spectra showed the induction process of oxygen-based functional group into laser treated PS surfaces. AFM and SEM observations demonstrated that a specific nanostructure was created on the laser-treated PS surface. Contact angle measurement indicated that water drop contact angle with one pulse laser-treated PS surface decreased and then gradually increased because of further laser pulses. The data from in vitro assays showed the significant cell attachment and growth onto laser treated samples.

In this paper, hydroxyapatite (HA), flour-hydroxyapatite (FHA) and fluorapatite (FA) powders have been synthesized in nanometric scales by sol-gel method. Structural changes, morphology, phase analysis and in vitro behavior of powders were studied. According to the XRD and SAED results, increasing the fluorine precursor caused an increase in the degree of crystallinity and crystallite size. FT-IR results demonstrated the replacement of F- in OH- positions and formation of FHA or FA. SEM and zetasizer studies showed that increasing of fluorine amounts raised the aptitude for agglomeration. According to the direct measurement during TEM studies,the crystallite sizes were found to be between 20 and 50 nm. The samples with higher amounts of fluorapatite resulted in the increasing of cells counts in the fibroblast cell culture experiment. So, fluor ion has a positive effect on biocompatibility of FHA powders.

The effect of short term usage of GnRH antagonist as pretreatment on superovulation in goats was evaluated. Statistical analysis was performed using t-test and showed that usage of GnRH antagonist as pretreatment can improve number of recovered embryos (p<0.05), but there were no statistically difference between treatment group versus control group in term of number of corpura lutea and cystic follicles(p>0.05). This study showed that usage of GnRH antagonist can improve superovulatory response in term of embryo recovery in goats. This study showed that usage of GnRH antagonist can improve superovulatory response in term of embryo recovery in goats.

Recently there are studies in developing new methods to increase bacterial adhesion onto polymeric surfaces that are used in biological application such as cell-based biosensors. In this study the surface of polyethylene terephthalate (PET) films were irradiated using CO2 and KrF excimer pulsed lasers and adhesion behavior of Escherichia coli k-12 (E. coli K-12) bacteria onto the irradiated surfaces was studied in vitro. The changes in the surface properties due to laser irradiation were characterized by scanning electron microscopy (SEM) and contact angle measurement. The results showed that laser treatment changes surface morphology and surface hydrophilicity. The number of bacteria that were adhered onto the surfaces was quantitatively investigated by fluorescent staining, microscopic observations and counting through Image Proplus software. The results showed that the number of adhered E. coli K-12 bacteria onto the irradiated surfaces by both CO2 and KrF lasers in comparison with unmodified surfaces was increased.