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Morphological changes of the chloride cells and the α_1b subunit gene expression of Na⁺-K⁺-ATPase in triploid rainbow trout (70.6 g average weight) were studied upon direct transferring to 6, 12 and 18 ppt salinities. Changes in abundance, distribution pattern, and the sectioned area of the chloride cells was studied through classic histology and Na⁺ K⁺-ATPase localization was performed through immunofluorescence light microscopy using a mouse monoclonal antibody IgGα5. Gene expression of Na⁺-K⁺-ATPase α_1b subunit was studied by semi-quantitative gene expression methods.No mortality occurred among the fish in all salinities during the 10-days experimental period and treated fish kept their plasma osmolality at standard physiologic levels. All the fish also showed similar distribution pattern in their chloride cells that were distributed on filaments, between and over lamella. Histological studies confirmed some abnormal morphological changes such as lamella interruption. Immunohistochemical studies showed the highest number of the chloride cells on lamella and between lamella in 18 ppt and the maximum sectional area of the chloride cells in freshwater. Gene expression of Na⁺-K⁺-ATPase α_1b subunit had direct correlation with increasing trend of salinity. In conclusions, triploid rainbow trout was found to be adaptable to the various experimented salinities and could be recommended for rearing in brackish water.

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Objective: Because of the necessity of more effective treatments for the nervous system injuries and considering the role of survivin in cellular proliferation and apoptotic cell death, we have monitored survivin gene expression changes during the course of regeneration in injured sciatic nerves and also L4-L6 segments of spinal cord. Materials and Methods: We used adult male NMRI mice as a model. After anesthetizing the animals, the right sciatic nerve was transected and at the indicated times (3, 6, 12, 24, 48, 96 and 144 hours) the animals were sacrificed and both distal and proximal segments of the transected sciatic nerve, intact left sciatic nerve and L4-L6 segments of spinal cord were dissected. The total RNA was extracted from each sample and semi-quantitative RT-PCR with specific primers for survivin and also 2-microglobulin genes, as an internal control, was performed. To determine cellular distribution of survivin protein, 6 days (144 hours) after the axotomy, survivin protein expression was evaluated using immunohistochemistry technique. Results: Our results demonstrated the expression of both survivin140 and survivin40 in distal and proximal segments of sciatic nerve with different intensity, where the expression of survivin140 was higher than survivin40. In spinal cord segments, only survivin140 expression was detected. In Immunohistochemistry analysis of spinal cord segments, both the nuclear and cytoplasmic distribution of survivin protein was observed. In contrast, survivin protein has not been detected in either distal or proximal segments of sciatic nerve. Conclusion: Our data suggest that survivin is differentially expressed and spliced during the course of regeneration in damaged nerve and spinal cord. It seems that manipulation of expression and/or splicing of survivin could potentially affect the process of regeneration in nerve and/or spinal cord injuries.

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Objective: Considering the importance of integrin molecules in the implantation and lack of sufficient information in the expression pattern of these molecules in various phases of estrous cycle. It seemed to be necessary to investigate these molecules in mouse endometrial during the various phases of oestrous cycle. Materials and Methods: Female NMRI mice (n=15) aged 6-8 weeks were studied. Various phases of estrous cycle including: proestrus, estrus, metestrus and diestrus were determined by vaginal smear. The mice were sacrificed (at least 3 per each phase) by cervical dislocation and the tissues were obtained from the middle 1/3 part of their uterine horns at each phase then the cryosections at thicknesses between 8-10 μ were obtained. Then the immunohistochemistry were done for integrins of 4, 1, v, 3 and their ligand osteopontine. Results: The integrins were expressed only in the metestrous phase of oestrous cycle in the different locations of mouse endometrium. The positive reactions were observed for αv, α4 and β3 in the apical and basal membrane of glandular epithelium. Also the positive reaction for β1 was found in surface and glandular epithelium as well as stroma. The osteopontin expression was seen in the apical membranes of surface and glandular epithelium and was not seen in other locations. Conclousion: It seems that expression of integrins in endometrium is based on their role in the implantation, therefore the molecules α4, β1 and OPN that are expressed on the surface epithelial may be involve in the adhesion of cell to cell and integrins of αv, β3 that are expressed in the glandular

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Objective: Estrogen receptor alpha protein status is determined by routine immunohistochemistry analysis in all malignant breast tumors. This assay has its limitations. RNA based techniques are potential complements for immunohistochemistry but it must be noticed that gene silencing may occur at different levels from RNA to protein. The aim of this study was the comparison of the results from these two assays and characterizing the tumors subgroup in which gene expression occurs at RNA level but the target protein is absent. Materials and Methods: 92 primary breast tumors including their clinical and IHC results were collected before treatment. Estrogen receptor gene expression of tumors was studied by Reverse Transcription Polymerase Chain Reaction (RT PCR). In this assay, GAPDH was used as a reference gene. Results: 36.6 % of tumors with negative estrogen receptor protein showed gene expression at mRNA level. In this subgroup most of the patient were older than 50 years and in stages 3 or 4 of breast cancer and had poor prognosis according to Nottingham prognostic index. Most cases of the perineural invasion have been seen in this subgroup. Conclusion: It seems that RT-PCR assay would enable us to recognize a subgroup of breast tumors with poor prognosis which expresses RNA but not protein.