فهرست مطالب شهناز رضوی

The purpose of this study is to evaluate the efficiency of electrospun scaffolds fabricated of poly (Lactic-co-glycolic acid) (PLGA) was coated by laminin, which are used as conduits to axon growth.

48 adult male Wistar rats were used in this study. These rats were divided into 6 groups, including a healthy control group, and in the other five groups, in addition to 10 mm damage to the sciatic nerve, various treatments were performed, including the Poly (L-lactide-co-glycolide) conduit group coated by laminin and filled with culture medium, PLGA conduit group coated by laminin and filled with rat adipose tissue-derived stem cells, PLGA conduit group coated by laminin containing gold nanoparticles and Brain Derived Neurotrophic Factor (BDNF) encapsulated in chitosan, PLGA conduit group coated by laminin containing gold nanoparticles and BDNF encapsulated in chitosan, which filled with rat adipose tissue-derived stem cells, or in the group Sixth, PLGA conduit group coated by laminin containing gold nanoparticles and BDNF encapsulated in chitosan, which filled with rat adipose tissue-derived stem cells suspended in alginate hydrogel. 12 weeks after implantation of conduits to the 10 mm defect of rat sciatic nerve, nerve regeneration and functional recovery were evaluated by behavioral tests and electrophysiology tests.

Three months post-operatively, the results of sensory analyses in all animals showed that sensory reinnervation on their foot returned almost completely, regardless of their experimental group. Also, different degrees of increase in CMAP (Compound Muscle Action Potential) amplitude were observed in all groups. However, their increase was significantly lower than the control group, while the latency in the groups containing nanoparticles and cells suspended in alginate did not show a significant difference compared to the control group.

The findings showed that electrophysiological and sensory tests can be effective methods to evaluate the peripheral nerve regeneration.

During the cancer treatment course, in addition to the destructive effects on the tumor cells, chemotherapy also damages healthy tissues and disrupts the balance of oxidant and antioxidant levels. The present study was conducted to evaluate the effect of omega-3 on sperm DNA methylation and histological structure of rat testis after treatment with combination chemotherapy using bleomycin, etoposide and cisplatin (BEP).

In this experimental study, 40 male rats were randomly divided into four groups of control, BEP, BEP+omega-3 and omega-3 (n=10). The control group was treated with 0.9% normal saline intraperitoneally for 18 weeks. The second group (BEP) first received 0.9% normal saline intraperitoneally for nine weeks. Then, it received BEP at 5.1 mg / kg for nine weeks, received etoposide and cisplatin at 5.7 mg/kg through gavage on days 1-5 of each week, and then received bleomycin at 75 mg/kg on days 2 of each week. The third group was gavaged with 0.9% saline for 9 weeks and then, orally received 300 mg/kg/day omega-3(capsule containing 1000 mg, 18% EPA and 12% DHA) for 9 weeks and in BEP + omega-3 group treated with BEP based on the same method and then orally received 300 mg/kg omega-3 as an antioxidant for the second nine weeks daily. Sperm DNA methylation and histological structure of rat testis including seminiferous tubules and basement membrane thickness were respectively evaluated by immunofluorescence staining and Periodic acid – Schiff (PAS) after 18 weeks of treatment in all groups.  

The mean percentage of sperm DNA methylation in the BEP-treated group (52.22±3.11) was significantly decreased compared to the control group (81.80±2.92) (p<0.001). However, the mean percentage of sperm DNA methylation increased significantly with omega-3 use after treatment with BEP (67±2.18) compared with BEP group (p<0.01). In light microscopy of testicular tissue, the number of spermatogonial cells (44.95±1.56), primary spermatocytes (47.60±1.45) as well as the epithelial thickness of seminiferous tubules (145.5±5.64) and basement membrane (7.07±0.29) decreased in the BEP-treated group in comparison with control group (p<0.001). However, the use of omega-3 after treatment with BEP significantly improved the number of germ cells and epithelial thickness of the seminiferous tubule and basement membrane (p<0.01).

Based on the results of this study, omega-3 as an antioxidant can improve the cytotoxic effects of chemotherapy drugs and it is recommended to be used for cancer patients after chemotherapy to reduce the cytotoxicity of these drugs.
 

Different studies have been done to obtain sufficient number of neuronal cells for treatment of central nervous system injuries. Adipose-derived stem cells have higher proliferation rate and more resistant to apoptosis. These cells can be induced to differentiate along several multilineage cells such as neuron-like cells. Alginate hydrogel is a polysaccharide polymer that has proper properties including biocompatibility with no immunogenicity. In this study, the effect of alginate hydrogel on the cell viability, proliferation rate and neurogenic differentiation of human adipose derived stem cells was evaluated at 14 days after induction.

Adipose-derived stem cells isolated from human, were cultured in neural induction media and seeded into alginate hydrogel. The cell viability and differentiation efficiency of encapsulated cells were evaluated via doubling time and real time quantitative reverse transcription polymerase chain reaction (real time RT-PCR) analysis, respectively. The collected data was analyzed using one-way ANOVA test.

The rate of proliferation of encapsulated cells significantly decreased as compared with control group (P < 0.001). The expression of nestin, glial fibrillary acidic protein (GFAP) and microtubule-associated protein 2 (MAP2) markers significantly decreased as compared with control group (P < 0.001).

Altogether cell viability and proliferation rate of encapsulated cells in alginate hydrogel significantly decreased as compared with control group, but alginate hydrogel can promote neural differentiation of adipose-derived stem cells.

In the present article، a comparison has been made between stages of evolution of man''s embryo according to Quran، hadiths، and embryology. Main stages of evolution of the embryo from thickened fluid (emshaj) to congealed blood (''ulqah) to embryo (muzghah) to bones and flesh (scientific names given to them by the Holy Quran) are in correspondence with their microscopic forms and characteristics. In all this stages، embryo''s length is not more than few millimeters. Nevertheless، embryology appeared in the second half of the 20th Century with all its modern technology and equipment has confirmed these Quranic descriptions. If one knows the stages of evolution of man''s embryo which is a manifestation of the Quran''s marvels، his belief in the Owner of the world of creation، God- the Exalted-، as well as the eternal miracle of the Sealing of Prophets، i. e. the Holy Quran، will become stronger.

Anatomists had been searching to find methods for preserving soft human tissues and produce natural samples with durable, dry, odorless, and portable in briefcase properties. Plastination is a modern method for preparing such tissue samples. In plastination, water and fat are extracted from tissues and replaced with a dissolver fluid, which in its turn is replaced with a special kind of polyester. Usually, the organs like hearts, lungs, kidneys, striated muscles, vessels, nerves, connective tissue, etc, which are treated with formalin, loss their beautiful color and take a dull appearance after fixation. Tissue staining with natural dyes is one method for somehow preserving tissue natural color and increasing its appearance activity to prepare better samples in terms of appearance and suitable clearance of different parts (valves, muscles, trabeculae…). Also, we have to prepare non fragile samples.

At first, some visceral organs (sheep hearts) were prepared and fixed by formalin 5% for 4 to 10 days. Then they were dissected for anatomic details and were put in a chemical dye called eosin and natural dye called ronnas. After dehydration by acetone in -25 °C and defeating with acetone in +30 °C, samples were put in the vacuum chamber to replace acetone instead of polymer under the vacuum pressure; finally the samples were cured with the ultra violate wave.

We found that after fixation and before plastination staining of organs with eosin and ronnas resulted in beautiful appearance of tissues.

Staining of organs resulted in beautiful appearance of tissues which are effective in increasing the attractively of teaching and learning anatomy. Also, it has affection in the raising appearance quality and has positive impression in the quality of education.